People with type 2 diabetes should 'save carbs for last'

"Diabetics should save bread for last at mealtime to keep their blood sugar under control," the Mail Online reports. A small study found that people with type 2 diabetes who saved their carbohydrates until the end of their meal were less likely to experience a sudden rise in their blood sugar (glucose) levels. The medical term for this spike in blood sugar levels is postprandial hyperglycaemia.

Postprandial hyperglycaemia is best avoided as not only can it make the day-to-day symptoms of diabetes worse, it has also been linked to an increased risk of developing cardiovascular disease.

It has been suggested that leaving carbohydrates until the end of a meal could slow the emptying of the stomach and give it a chance to digest the protein and vegetables first, which could help prevent a blood glucose spike. The researchers wanted to see whether this was true.

This study included just 16 people who ate the foods of their meal in different orders to test which order was most effective at lowering blood sugar and related hormones. They either ate carbohydrates first, carbohydrates last, or all nutrients together at the same time.

The researchers generally found that consuming carbohydrates last was better at lowering blood sugar levels and insulin secretion when compared to the other ways of eating carbohydrates.

While the results are interesting, the study was far too small to form the basis of any firm medical guidance. For now, it's best to follow current advice, which is to consume a healthy diet and keep active to help you manage your blood sugar level. This will also help you control your weight and generally feel better.

 

Where did the story come from?

The study was carried out by US researchers from Weill Cornell Medical College, Columbia University and Boston Children's Hospital. It was funded by the Louis and Rachel Rudin Foundation Grant, and Diane and Darryl Mallah from The Diane and Darryl Mallah Family Foundation.

The study was published in the peer-reviewed BMJ Open Diabetes Research & Care. It is available on an open-access basis and can be read for free online.

The Mail Online's coverage generalised the results to all diabetics – but the study only looked at those with type 2 diabetes. People with type 1 diabetes typically require insulin injections to keep their blood sugar levels under control.

It also presented the findings as if they were a solid recommendation, but this is not the case, especially given this was an early-stage study using a very small number of people.

 

What kind of research was this?

This was a randomised crossover trial that aimed to determine the best time during a meal to eat carbohydrates to lower blood glucose levels in individuals with type 2 diabetes. The researchers also wanted to explore whether changing the order in which foods were eaten during a meal had any effect on the secretion of insulin and other glucose-regulating hormones.

Previous research has suggested that saving carbohydrates until the end of the meal lowers blood glucose levels. This follows on from the notion that eating proteins at the start of a meal stimulates insulin secretion (which helps control glucose levels). However, data on this hypothesis is limited and the researchers of this study wanted to investigate this idea further.

Crossover trials such as this are often used when the sample size is very small. Each person acts as their own control, which effectively increases sample size. The study would ideally need to be conducted using a much larger sample with people randomised to consume nutrients in different orders over a longer period to compare effects.

 

What did the research involve?

The researchers recruited 16 people with type 2 diabetes, between the ages of 35 and 65. All the participants had a body mass index (BMI) of between 25 and 40kg/m2 (covering the range from overweight to severely obese) and had been diagnosed with diabetes within the last 10 years.

All 16 people consumed the same meal on three separate days spaced out one week apart, with each meal following a 12-hour overnight fast.

The meals varied in terms of the order in which the nutrients were eaten. Participants were assigned the following meal types in random order:

• carbohydrates first, followed by protein and vegetables 10 minutes later
• protein and vegetables, followed by carbohydrates 10 minutes later
• all nutrients eaten together

Blood samples were taken before consumption, and then at 30-minute intervals up to 180 minutes. The following were measured:

• glucose levels
• insulin levels (a hormone released in response to high glucose levels)
• glucagon-like peptide-1 (GLP-1, a hormone secreted in the gut in response to food to signal the release of insulin)
• glucagon levels (a hormone released in response to low glucose levels)

All participants were instructed to maintain their usual level of diet and physical activity during the full study period.

 

What were the basic results?

The following was observed:

• When carbohydrate was consumed last, lower levels of insulin were secreted (24.8% lower than the meal with carbohydrates first), which would suggest a smaller spike in glucose. There was no significant difference between eating carbohydrates last and having all nutrients together.
• Consistent with this, glucose levels were 53.8% and 40.4% lower in the meal with carbohydrates last compared to having carbohydrates first and all nutrients together, respectively.
• The GLP-1 levels were higher in people who ate carbohydrates last.
• Glucagon levels were not significantly different between the three meal conditions.

 

How did the researchers interpret the results?

The researchers concluded: "In this study, we demonstrated that the temporal sequence of carbohydrate ingestion during a meal has significant impact on postprandial glucose regulation. These findings confirm and extend results from our previous pilot study; the inclusion of a third nutrient order condition, a sandwich, had intermediate effects on glucose excursions compared with carbohydrates last versus carbohydrates first."

 

Conclusion

This crossover trial investigated the optimal time to eat carbohydrates during a meal to lower blood glucose levels in individuals with type 2 diabetes. It generally found that consuming carbohydrates last was better at lowering glucose levels and reducing insulin secretion when compared to having carbohydrates first or all nutrients together.

The researchers say that suggesting people with type 2 diabetes follow this advice may be an effective behavioural strategy to improve glucose levels after meals.

Although the findings are interesting, there are a few points to note:

Most importantly, this study was very small. A study using a much larger sample could give completely different results. Ideally the findings would need to be verified in a well-designed trial that randomised a much larger number of people with type 2 diabetes to consume their nutrients in a specific order, and then followed their response to this pattern over a longer period of time.

There may be other factors affecting individual responses to the order of carbohydrate consumption – for example, the level of physical activity was not standardised across all participants. Again this is another factor that would need to be controlled in a larger trial.

We are all different – and saving carbohydrates until the end of a meal may only be effective for some people with type 2 diabetes, and not others.

The findings cannot be applied to people with type 1 diabetes.

These findings may pave the way for further research through larger trials, which in time may result in a change in the current recommendations for meal consumption for people with type 2 diabetes.

However, they have no current implications. For now, a healthy diet and keeping active will help you manage your blood sugar level. This will also help you control your weight and generally feel better.

Links To The Headlines

Don't eat the bread first: Saving carbs for last at mealtime may help control blood sugar levels for diabetics, study finds. Mail Online, September 29 2017

Links To Science

Shukla AP, Andono J, Touhamy SH, et al. Carbohydrate-last meal pattern lowers postprandial glucose and insulin excursions in type 2 diabetes. BMJ Open Diabetes Research & Care. Published online September 14 2017

 

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Reports that frequent drinking prevents diabetes are inaccurate

"Drinking a moderate amount of certain drinks such as wine three to four times a week reduced diabetes risk by about 30%," The Guardian reports. That was the main reported finding of a Danish study looking at the impact of alcohol on diabetes risk.

Researchers looked at a group of more than 70,000 people who had completed a survey about their health and lifestyle in 2007-2008, which included questions about their drinking habits. They then checked whether any of the participants had been diagnosed with diabetes (either type 1 or 2) about four years after completing the survey, and looked at survey data for these people.

The researchers noticed a pattern that suggested people who developed diabetes were less likely to have drunk alcohol moderately and frequently compared with those who did not develop diabetes. The researchers reported that the lower risk for diabetes was associated with 14 units per week for men and seven units for women (current recommendations are that men and women shouldn't regularly drink more than 14 units per week).

However, the study had various weaknesses, which means it cannot conclusively show that drinking frequently and moderately protects against diabetes. For example, people were only asked about their drinking habits and other lifestyle choices at a single time point. Also, the study doesn't tell us whether those habits changed over the period in which people were monitored for diabetes.

Even if an association does exist, there are far healthier ways to reduce your diabetes risk, such as achieving or maintaining a healthy weight.

 

Where did the story come from?

This study was an analysis of data from the general Danish population that had been recorded in a previous cohort study. This particular piece of research was carried out with no specific funding, but the survey data had been funded by the Ministry of the Interior and Health, and the Tryg Foundation. It was published in the peer-reviewed journal Diabetologia.

The suggestion that regularly drinking alcohol may be good for you was met with glee by the UK media. The limitations of the study, or the lack of a definitive cause and effect, were not reported fully.

However, some sources carried sensible advice from independent experts, such as Dr Emily Burns, the head of research communications at Diabetes UK, who was quoted in The Guardian as saying: "While these findings are interesting, we wouldn't recommend people see them as a green light to drink in excess of the existing NHS guidelines, especially as the impact of regular alcohol consumption on the risk of type 2 will be different from one person to the next."

There were several reports that wine was particularly beneficial because it has "a role in helping to manage blood sugar", but this was based only on the authors' comments rather than on the results of the research.

 

What kind of research was this?

This cohort study assessed people for diabetes in 2012 about four years after their lifestyles had been assessed in 2007-2008. The researchers aimed to examine whether there was any association between alcohol drinking patterns and the risk of developing diabetes in people who did not already have the condition. They looked at the amount that people drank, how often they drank, and what types of alcohol were consumed.

The study benefitted from involving a large number of people in the Danish population, which meant a range of drinking patterns were found, and there were sufficient numbers of cases of diabetes to look for associations.

However, a major weakness of the study was that it only looked at alcohol drinking patterns at a single point in time. And people's drinking habits are known to change over time according to their circumstances, preferences and other health issues.

The researchers did attempt to take into account other confounding factors (such as diet and exercise) that may have influenced the results, but these factors may not have been recorded in enough detail to be useful, and other factors might not have been recorded at all.

 

What did the research involve?

The researchers identified 70,551 people from the Danish Health Examination Survey (an ongoing nationwide study) who were eligible to participate. These people had already completed a questionnaire in 2007-2008 about their lifestyle and health. People had to meet the following criteria to be selected for participation:

• no existing diagnosis of diabetes at the start of the study
• not pregnant and haven't recently given birth (within the last six months)
• have provided at least some information about their drinking habits in the questionnaire

Information about drinking patterns was collected from questionnaires that people completed by themselves on how often they drank, whether they ever binged and how often this happened, and how much they drank different types of drinks (beers, wines or spirits).

The researchers also looked at information that had been collected at the start of the study on the following confounding factors:

• age
• sex
• body mass index
• education
• smoking status
• diet
• leisure-time physical activity
• high blood pressure (current or previous)
• family history of diabetes

A diagnosis of diabetes was recorded using the Danish National Diabetes Register, which uses five different sources to detect diabetes cases, but does not distinguish between type 1 and type 2. During the course of the study the researchers carried out a "sensitivity analysis", where they excluded two of the diabetes cases because of concerns the data was unreliable.

The participants were followed up in the study until it ended in December 2012, unless they emigrated, died or developed diabetes before then. The researchers carried out an analysis that looked at the risk of developing diabetes over time, taking into account different risk factors. They used appropriate statistical methods for dealing with missing data.

 

What were the basic results?

During the course of the study, 859 men and 887 women developed diabetes. When looking at the average amount that people drank over the course of a week, they found that the lowest risk of diabetes was observed in:

• men who drank 14 drinks a week (Hazard ratio [HR] 0.57, 95% Confidence Interval [CI] 0.47 to 0.70)
• women who drank nine drinks a week (HR 0.42 (95% CI 0.35 to 0.51))

Frequency of drinking

After adjusting for other factors, the researchers reported the consumption of alcohol on three to four days a week was associated with a lower risk of developing diabetes for men: HR 0.73 (95% CI 0.59 to 0.94) and for women: HR 0.68 (95% CI 0.53 to 0.88).

The researchers also looked at binge drinking and found no clear link between binge drinking and risk of diabetes.

Type of alcohol

Researchers noticed a number of patterns in terms of what types of alcohol people drank.

Men who drank 1-6 glasses of beer a week were found to have lower diabetes risk than those who did not.

In contrast, women who regularly drank spirits seven or more times a week had an increased risk of diabetes compared with those who drank spirits once a week or less. However, the researchers failed to take into account that some people drink a mixture of different types of alcohol either on a single occasion or over a week.

 

How did the researchers interpret the results?

The authors concluded that "light to moderate" alcohol consumption was associated with a lower risk of diabetes when compared to no alcohol consumption at all. They also noted that frequent consumption was associated with the lowest risk, even after taking into account the amount people drank on average during a week.

They noted that the strengths of their study included its size, the fact that they distinguished between people who currently didn't drink from those who had never drunk at all, and that their results were consistent even when they adjusted various conditions.  

 

Conclusion

Although this study found an interesting association between alcohol drinking habits and risk of developing diabetes, this study does not present strong enough evidence to recommend adopting a particular drinking pattern to reduce diabetes risk.

This study had a number of limitations that weaken confidence in the results:

• People were only asked about their drinking habits and other risk factors at a single time point. The study doesn't tell us whether those habits changed over the period in which people were monitored for diabetes. Most studies related to alcohol consumption also run the risk that people are not always completely accurate when describing what and how much they drink.
• The way diabetes cases were recorded for the study did not distinguish between type 1 and type 2 diabetes, even though these conditions have different causes and treatments.
• The study only followed people up for an average of just under five years, whereas a condition like diabetes may develop due to risk factors experienced over a longer period.
• The information collected on diet may have been too simplistic to properly allow an understanding of how nutrition may also affect the diabetes risk of the people in the study.
• Although the researchers excluded people from the study if they already had a diagnosis of diabetes at baseline, they didn't exclude people if they had other chronic health conditions, some of which may contribute to diabetes risk. The only other condition that was considered in the analysis was high blood pressure.

Overall, it is unclear whether the link between moderate alcohol drinking and diabetes is real. It is not proof that starting to drink more, especially for those who do not currently drink, is useful in preventing diabetes. There are other risks, such as liver damage, to consider when drinking frequent or large volumes of alcohol above recommended limits.

If you are concerned that you might be at risk of developing diabetes, speak to your GP about the ways that lifestyle change can reduce your risk.

Links To The Headlines

Regular alcohol consumption could cut diabetes risk, study finds. The Guardian, July 28 2017

Drinking a few times a week 'reduces diabetes risk'. BBC News, July 28 2017

Drinking alcohol three to four days a week 'could reduce risk of diabetes'. The Independent, July 28 2017

Drinking wine three times a week 'cuts diabetes': Risk can be reduced by nearly a third by consuming alcohol 'little and often'. Mail Online, July 28 2017

Drinking most days may protect against diabetes - new study. The Daily Telegraph, July 28 2017

Drinking alcohol regularly could cut diabetes risk - and red wine is your 'healthiest' option. Daily Mirror, July 28 2017

Links To Science

Holst C, Becker U, Jørgensen ME, et al. Alcohol drinking patterns and risk of diabetes: a cohort study of 70,551 men and women from the general Danish population. Diabetologia. Published online July 27 2017

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Vegetarian dieting may lead to greater weight loss

"Dieters who follow a vegetarian eating plan lose nearly twice as much weight," the Daily Mail reports following the results of a new study.

Researchers randomly assigned two groups of people with type 2 diabetes to either a vegetarian diet or a standard weight loss diet. They found those on the vegetarian diet lost more weight and more body fat.

Both diets involved reducing daily calorie consumption by 500 calories a day. The standard weight loss diet in this study is a diet recommended for people with diabetes. The vegetarian diet consisted of leafy vegetables, nuts, fruit, and grains.

After six months, researchers found those in the vegetarian group had lost about twice as much weight as those in the other group – 6.2kg, compared with 3.2kg.

But this isn't surprising – more people stuck to this diet compared with those on the standard weight loss diet.

The media failed to make it clear that the study was carried out on overweight people with type 2 diabetes, and therefore the findings may not apply to other people trying to lose weight.

If you have type 2 diabetes and you're overweight, you should aim to lose weight as this will help control your symptoms. Some people may benefit from switching to a vegetarian diet, but it's not a magic bullet.

The important thing if you're trying to lose weight is to reduce your daily calorie intake and get more exercise. Learn more in the weight loss guide.

Where did the story come from?

The study was carried out by researchers from the Institute for Clinical and Experimental medicine, Charles University, and the Institute of Endocrinology, all in the Czech Republic, and the Physicians Committee for Responsible Medicine in the US.

It was funded by a project grant from the Ministry of Health in Prague.

The study was published in the peer-reviewed Journal of the American College of Nutrition on an open access basis, so it's free to read online.

The UK media's coverage of the study was generally accurate, although the Mail's claim that "vegetarian dieters find their eating plan and exercise routine easier to stick to" was unfounded. 

There may be many reasons why a few more participants in the vegetarian group stuck to their diet. And, because of the small numbers involved in the study (37 in each group), the results could be down to chance.

What kind of research was this?

This randomised controlled trial (RCT) involved participants with type 2 diabetes who either had a vegetarian diet or a conventional diabetic diet. They then had their fat measures taken.

An RCT is the best way of comparing the effect of diets on health outcomes, as it allows control over other variables that might potentially affect the results.

What did the research involve?

The researchers took a group of 74 men and women who had type 2 diabetes and assigned half of them to a vegetarian diet and the other half to a conventional diabetic diet.

All the participants had a body mass index (BMI) over 25, meaning they were overweight.

The researchers followed them at three months and six months to measure how much weight they'd lost.

Both diets were calorie restricted (reduced by 500 kcal per day). The vegetarian diet consisted of vegetables, grains, legumes, fruits, and nuts, and was around 60% carbohydrates, 15% protein and 25% fat. The conventional diabetic diet was made up of around 50% carbohydrates, 20% protein, and less than 30% fat.

Adherence to the diets was measured as part of the research. High adherence was defined as daily energy intake of no more than 100kcal in excess of what had been prescribed, while medium adherence was no more than 200kcal in excess. 

Participants were asked to not alter their existing exercise habits for the first 12 weeks, and were then prescribed tailored exercise programmes to do three times a week.

MRI scans of the participants' thigh muscles were taken at baseline, three months, and six months. Two types of fat were measured: fat just under the connective tissues (subfascial) and fat just under the skin (subcutaneous).

What were the basic results?

The vegetarian diet was almost twice as effective at reducing body weight compared with the conventional diet.

Overall, participants lost 6.2kg (95% confidence interval [CI] -6.6 to -5.3) on the vegetarian diet, versus 3.2kg (95% CI -3.7 to -2.5) on the standard weight loss diet.

The greater weight loss seen in people on the vegetarian diet was also accompanied by greater muscle loss of -5.0cm2 (95% CI -5.7 to -4.3) versus -1.7cm2 (95% CI -2.4 to -1.0).

Subfascial fat was only reduced in those who were on a vegetarian diet (-0.82 cm2, 95% CI -1.13 to -0.55).

When it came to sticking to the diet, there was:

• high adherence in 55% of the participants on the vegetarian diet and in 32% on the conventional diet
• medium adherence in 22.5% of participants on the vegetarian diet and in 39% on the conventional diet
• low adherence in 22.5% of participants on the vegetarian diet and in 29% on the conventional diet

How did the researchers interpret the results?

The authors concluded that their data "indicate that a vegetarian diet is more effective in reducing subfascial fat and tends to also reduce intramuscular fat more than a conventional hypocaloric diabetic diet.

"Our data suggest the importance of both subcutaneous and subfascial fat in relationship to glucose and lipid metabolism."

They say that, "Further research is needed to determine how dietary interventions with different diet composition can influence thigh fat distribution in relationship to glucose and lipid metabolism." 

Conclusion

This research appears to show that there's some association between following a vegetarian diet and a greater reduction in body mass and subfascial fat.

But this study has a number of limitations, and the conclusions drawn by the researchers should be interpreted cautiously.

• There was lower adherence to the diet in the conventional diet group than the vegetarian one. This means the finding of a greater reduction in body mass in the vegetarian group is unsurprising.
• The thigh was the only part of the body where fat measurements were taken. It could be the case that reduction in abdominal fat – a big risk factor for type 2 diabetes – didn't differ between the groups.
• The proportion of fat recommended in the vegetarian diet was lower than in the conventional diet, so it would be expected that fat reductions would be greater in the vegetarian group.
• The vegetarian diet was actually almost vegan, as the only animal product allowed was a small amount of yoghurt. Following a vegetarian diet without these extra restrictions might not bring about the same results.
• The vegetarian group also lost more muscle mass than the conventional group, particularly when doing their usual exercise routine. This might be an unwanted outcome and a disadvantage when compared with the usual diet.
• The study involved a relatively small sample of overweight people with type 2 diabetes. The findings may not be applicable to the general population.

Based on the findings of this study, we can't say that a vegetarian diet is more beneficial than a conventional diet for people with type 2 diabetes.

What we can say is that the vegetarian diet resulted in greater weight loss, and a reduction in some types of bodily fat, for the people who took part in this small study.

The additional loss of muscle mass might mean it's not preferable to the conventional diet currently recommended for people with diabetes.

If you have type 2 diabetes and are concerned about your weight, talk to your GP or diabetes care team. Achieving a healthy weight should help you control your symptoms and reduce the risk of complications.

Find out more about living with type 2 diabetes.

Links To The Headlines

Vegetarian diets twice as effective for weight loss as carnivorous meal plans, says study. The Independent, June 13 207

Why a vegetarian diet guarantees slimming success: Cutting out meat nearly doubles weight loss by changing how we store fat. Daily Mail, June 14 2017

Links To Science

Kahleova H, Klementova M, Herynek V, et al. The Effect of a Vegetarian vs Conventional Hypocaloric Diabetic Diet on Thigh Adipose Tissue Distribution in Subjects with Type 2 Diabetes: A Randomized Study. Journal of the American College of Nutrition. Published online June 10 2017

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Daily diet of fresh fruit linked to lower diabetes risk

"Eating fresh fruit daily could cut risk of diabetes by 12%," the Mail Online reports.

A study of half a million people in China found those who ate fruit daily were 12% less likely to get type 2 diabetes than those who never or rarely ate it.

It was also found that people with diabetes at the start of the study who ate fruit regularly were slightly less likely to die, or to get complications of diabetes, such as eye problems (diabetic retinopathy), during the study than those who ate fruit rarely or never.

Many people with diabetes in China avoid eating fruit, because they are told it raises blood sugar. However, the study suggests fresh fruit may actually be beneficial for people with and without diabetes.

Fruits which release sugars more slowly into the blood, such as apples, pears and oranges, are the most popular in China, according to the researchers. So this may be the preferred option if you are worried about diabetes risk, or have been diagnosed with diabetes.

The study doesn't show that fruit directly prevents diabetes or diabetes complications, as an inherent limitation of this type of study is that other factors could be involved. And it doesn't tell us how much fruit might be too much.

Overall, the research suggests fresh fruit can be part of a healthy diet for everyone.

 

Where did the story come from?

The study was carried out by researchers from the University of Oxford, and Peking University, Chinese Academy of Medical Sciences, China National Center for Food Safety Risk Assessment, Non-communicable Disease Prevention and Control Department, and Pengzhou Center for Disease Control and Prevention, all in China. It was funded by the Kadoorie Charitable Foundation.

The study was published in the peer-reviewed journal PLOS Medicine on an open-access basis, so it's free to read online.

The Mail's report was basically accurate, although it did not point out that this type of study cannot prove cause and effect. The report confused some readers by saying that fruit does not raise blood sugar because it is metabolised differently to refined sugar.

However, what the study found was that fruit-eaters' blood sugar was not on average higher than that of non-fruit eaters. Like most food, the rise in sugar levels after eating fruit is usually temporary.

The Sun's report was poorly written and contained some basic grammatical errors.

 

What kind of research was this?

This was a large-scale prospective cohort study. Researchers wanted to look for associations between fruit eating, diabetes and complications of diabetes.

However, while this type of study is good for spotting links, it cannot prove that one factor causes another.

 

What did the research involve?

Researchers used information from a big ongoing cohort study called the China Kadoorie Biobank Study, which recruited half a million adults aged 30 to 79 between 2004 and 2008.

Participants filled in questionnaires about their health, diet and lifestyle and had measurements taken of their blood sugar, blood pressure, cholesterol and other health-related factors. The diet questionnaires were repeated over the course of the study. After an average seven years of follow-up, researchers looked to see how fruit consumption related to diabetes.

Some people in the study (almost 6%) had diabetes at the start of the study. While not actually specified in the study, we assume the majority of these cases were type 2 diabetes. Type 1 diabetes usually begins in childhood and is less common than type 2.

About half of them had previously been diagnosed, and half were diagnosed due to their blood sugar readings taken during the study. China's Disease Surveillance Points system was used to identify any deaths and cause of death during the study. Disease registries and health insurance claims were used to look into diabetes-related health complications.

The researchers took the average responses from the diet questionnaires to establish how regularly people ate fruit, to account for possible changes in dietary habits.

They adjusted the figures to take account of potential confounding factors including age, age at diabetes diagnosis, gender, smoking, alcohol consumption, physical activity and body mass index. 

 

What were the basic results?

Only 18.8% of people surveyed reported eating fruit daily, and 6.4% said they never or rarely ate fruit. Some 30,300 people had diabetes at the start of the study, and there were 9,504 new cases of diabetes in the seven years of follow up, or 2.8 for each 1,000 people each year.

• People who ate fresh fruit daily were 12% less likely to develop diabetes than those who never or rarely ate fresh fruit (hazard ratio (HR) 0.88, 95% confidence interval (CI) 0.83 to 0.93).
• Of the people with diabetes at the start of the study, 11.2% died during follow up (16.5 for every 1,000 people each year).
• People with diabetes who ate fresh fruit on three days a week or more were 14% less likely to die of any cause, compared to those who ate fresh fruit less than one day a week (HR 0.86, 95% CI 0.80 to 0.94). They were also less likely to die from diabetes-related causes or cardiovascular disease, specifically.
• People with diabetes who ate fresh fruit daily were also 14% less likely to have complications of damage to their large blood vessels (such as heart attack or stroke) than those who ate fresh fruit never or rarely (HR 0.86, 95% CI 0.82 to 0.90). They were also 28% less likely to have small blood vessel complications, such as eye or kidney disease (HR 0.72, 95% CI 0.63 to 0.83).

 

How did the researchers interpret the results?

The researchers say their results "provide strong evidence in support of current dietary guidelines that fresh fruit consumption should be recommended for all, including those with diabetes."

They say that people with diabetes in China eat much less fruit than people without diabetes, because of concerns about sugar in fruit. They say the study shows that better health education is "urgently needed" in China and other Asian countries where diabetes is common, and many people misunderstand the effects of eating fresh fruit.

They speculate that "natural sugars in fruit may not be metabolised in the same way as refined sugars," although their paper did not investigate this.

 

Conclusion

The study findings – that eating fresh fruit every day does not raise the risk of diabetes, and may reduce it – are reassuring and in line with dietary advice in the UK. It's also helpful to see evidence that people who already have diabetes are likely to benefit from fresh fruit as well, because there has not been much research into fruit-eating for people with diabetes.

However, it's a step too far to say that fresh fruit prevents diabetes or diabetes complications. Fresh fruit is just one part of a healthy diet, and diet is just one of the things that may affect someone's risk of getting diabetes. This type of study can't tell us whether fresh fruit actually protects against diabetes, because it can't account for all the other health and lifestyle factors involved.

Though it would be expected that the results of this large scale study should be applicable to other populations, there may be differences between people from China and other populations. This could include differences in prevalence of diabetes and its risk factors, differences in healthcare (for example, diagnostic criteria and methods for coding health outcomes in databases), and other environmental and lifestyle differences, including fruit consumption.

The study didn't ask people which types of fruit they ate, but the researchers say the most commonly eaten fruits in China are apples, pears and oranges, which release sugars more slowly into the blood stream than bananas, grapes and tropical fruits.

It's important to make a distinction between whole fresh fruit, which contains lots of fibre, and fruit juice, which is very high in sugar. Previous research that we reported on in 2013 found that fruit may lower diabetes risk, but fruit juice may raise it.

The most effective method of reducing your diabetes risk is to achieve or maintain a healthy weight, through a combination of regular exercise and healthy eating. Read more about preventing diabetes.   

Links To The Headlines

Eating fresh fruit daily could cut risk of diabetes by 12%: New research reduces fears it is unhealthy because of high sugar content. Mail Online, April 12 2017

Eating fresh fruit every day and making lifestyle changes lower the risk of diabetes, study says. The Sun, April 12 2017

Links To Science

Du H, Li L, Bennett D, et al. Fresh fruit consumption in relation to incident diabetes and diabetic vascular complications: A 7-y prospective study of 0.5 million Chinese adults. PloS Medicine. Published online April 11 2017

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Children's screen time linked to diabetes risk factors

"Children who are allowed more than three hours of screentime a day are at greater risk of developing diabetes," The Guardian reports.

In a new study, UK researchers found a link between three hours or more of screen time and risk factors for type 2 diabetes, such as higher body fat.

The study used data from almost 4,500 children aged around 10 years collected between 2004 and 2007. They found that children with more than three hours of screen time per day had higher body fat and insulin resistance compared to children with an hour or less per day. Screen time was defined as time spent watching television and using computers or games consoles.

It is unlikely that the screen time itself is causing an increase in risk; more that this could indicate a more sedentary lifestyle.

One concern is that the data was collected before the use of smartphones and tablets became widespread in children. So it could be the case that screen time use has now increased among children, but we would need further research to confirm this.

Recent US guidelines (there are currently no UK guidelines) recommend no screen time for infants under 18 months, one hour for children aged 2-5, and then older children should be assessed on a case by case basis by their parents.

The study supports current physical activity recommendations for children which say they should do at least an hour's exercise every day. Sticking to this will help reduce the risk of chronic diseases such as type 2 diabetes in later life.

 

Where did the story come from?

The study was carried out by researchers from the University of London and the University of Glasgow. Funding was provided by the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care (CLAHRC). Data collection was funded by grants from the Wellcome Trust, the British Heart Foundation and the National Prevention Research Initiative.

The study was published in the peer-reviewed medical journal Archives of Disease in Childhood.

There were no conflicts of interest reported by the research team.

The UK media generally reported on this study accurately, though none of the media outlets really explains why this link may have been seen or that the study can't prove that screen time itself increases risk.

The Mail Online provided a number of figures from other sources to add context to the study findings. We are unable to comment on the accuracy of these sources. 

 

What kind of research was this?

This is a cross-sectional survey looking into association between daily screen time and risk markers for type 2 diabetes and cardiovascular disease in children aged nine and 10 years.

Type 2 diabetes and obesity are increasing in adults and children. The effect of sedentary behaviour such as watching television and using computers, known as "screen time", are a cause for concern and associations have been seen between prolonged screen time and body fatness in children.

Using data from this survey the researchers were able to identify potential risk factors, however due to the nature of this study design they would not be able to prove that one thing causes the other. The researchers say they can use their findings to design further studies to prove causation.

A randomised controlled trial would be required to prove such a link. However, a trial that randomises children to different amounts of sedentary time or physical activity and then follows them for sufficient time to observe outcomes may be neither feasible nor ethical.

 

What did the research involve?

This was a cross-sectional study known as The Child Heart and Health Study in England.

Researchers carried out a survey of primary school children aged nine and 10 years from London, Birmingham and Leicester. A single research team collected key information between October 2004 and February 2007. Some of the information recorded was as follows:

• ethnic origin (based on the ethnicity of both parents)
• socioeconomic status
• height
• weight
• skin fold measurements
• fat mass
• blood glucose and insulin levels
• insulin resistance – a measurement of how the body's cells respond to insulin
• cholesterol
• blood pressure
• pubertal status measured in girls (girls tend to start puberty earlier than boys)

On the same day as the physical measurements were taken, children completed a questionnaire asking "How many hours each day do you spend watching television or video and playing computer games?"

The children had to tick the most appropriate response, the options were:

• none
• an hour or less
• one to two hours
• two to three hours
• more than three hours

In a sub-group of children, activity was measured using a monitor worn around the waist.

When analysing the findings the researchers attempted to account for the effects of confounding factors such as socioeconomic status, physical activity and pubertal status.

 

What were the basic results?

The analysis focused on the 4,495 children (2,337 girls and 2,158 boys) who had screen time data, all physical measurements and a fasting blood sample. More than 2,000 children had physical activity data collected from the waist monitor.

The most commonly reported screen time duration was one hour or less (37%), with 18% reporting more than three hours and 4% reporting no screen time at all.

Boys were more likely to have more than three hours of screen time a day, 22% compared to 14% of girls.

Differences were seen between ethnic groups, a higher proportion of black African-Caribbean children (23%) had more than three hours of daily screen time compared with white Europeans (16%) and South Asians (16%).

Children reporting more than three hours of screen time were found to have a higher level of body fat than those with an hour or less screen time.

This was as measured by ponderal index (ponderal means related to weight – the index is a measure of kg/m3; which was on average 1.9% higher), skinfold thickness (4.5% greater), fat mass index (3.3% higher) and leptin (a hormone that controls hunger – 9.2% higher).

They also had higher levels of blood insulin and insulin resistance compared to children taking one hour or less, though there was little link with blood glucose control.

 

How did the researchers interpret the results?

The researchers conclude: "Strong graded associations between screen time, adiposity and insulin resistance suggest that reducing screen time could facilitate early T2D [type 2 diabetes] prevention. While these observations are of considerable public health interest, evidence from randomised controlled trials is needed to suggest causality."

 

Conclusion

This cross sectional study aimed to investigate the association between markers for type 2 diabetes and the amount of screen time a child has.

The study found an association between higher levels of screen time and higher body fat and insulin resistance. However, as mentioned, this type of study is not able to prove cause and effect. It is most likely not the screen time itself that is the cause of these factors, more that this could indicate a generally less healthy and more sedentary lifestyle. A similar link might be found for children who spend more time reading books instead of taking physical activity.

The researchers have tried to adjust for physical activity and socioeconomic status that could be influencing the link. However, it is possible that some confounding remains in the model or that other important factors were missed – diet being a notable possibility. It's also possible that children who reported more screen time may have had other health conditions which were not accounted for in the analysis that could have increased their risk.

Other important limitations are that the amount of screen time was self-reported and children may not have remembered or reported this accurately. The measures of body fat and blood glucose control were also one-off measurements taken at single point in time. They don't tell us that the child will go on to develop type 2 diabetes.

Nevertheless the study suggests a reduction in screen time could be beneficial in improving health and possibly reducing the risk of type 2 diabetes and other obesity-related diseases in later life.

One pressing concern is that the data gathered in the study was taken before the use of smartphones and tablets became widespread in older children. Smartphones became commonly used around 2008 to 2010 and the first tablet (the iPad) was released in 2010. So it could well be the case that screen time has now increased in older children.

With these concerns in mind it is important that children are taught to compensate for time spent "gawping at gadgets" (as the Mail puts it) with time spent being physically active.

Guidelines for children and young people recommend that to maintain a basic level of health at least 60 minutes of physical activity every day should be taken; this could be cycling, playground activities or more vigorous activity, such as running and tennis. Exercises for strong muscles and bones are recommended three days a week such as push-ups, jumping and running.

Read more advice about encouraging children to be more physically active.

Links To The Headlines

Screentime linked to greater diabetes risk among children. The Guardian, March 13 2017

Watching TV three hours a day linked to child diabetes. The Independent, March 13 2017

Children's risk of developing Type 2 diabetes soars with just three hours of screen time a day. Mail Online, March 13 2017

Kids who spend three hours a day watching telly or playing video games ‘flirting with diabetes’. The Sun, March 13 2017

Links To Science

Nightingale CM, Rudnicka AR, Donin AS, et al. Screen time is associated with adiposity and insulin resistance in children. Archives in Disease for Childhood. Published online March 13 2017

via NHS Choices: Behind the headlines More READ

Children's screen time linked to diabetes risk factors

"Children who are allowed more than three hours of screentime a day are at greater risk of developing diabetes," The Guardian reports.

In a new study, UK researchers found a link between three hours or more of screen time and risk factors for type 2 diabetes, such as higher body fat.

The study used data from almost 4,500 children aged around 10 years collected between 2004 and 2007. They found that children with more than three hours of screen time per day had higher body fat and insulin resistance compared to children with an hour or less per day. Screen time was defined as time spent watching television and using computers or games consoles.

It is unlikely that the screen time itself is causing an increase in risk; more that this could indicate a more sedentary lifestyle.

One concern is that the data was collected before the use of smartphones and tablets became widespread in children. So it could be the case that screen time use has now increased among children, but we would need further research to confirm this.

Recent US guidelines (the are currently no UK guidelines) recommend no screen time for infants under 18 months, one hour for children aged 2-5, and then older children should be assessed on a case by case basis by their parents.

The study supports current physical activity recommendations for children which say they should do at least an hour's exercise every day. Sticking to this will help reduce the risk of chronic diseases such as type 2 diabetes in later life.

 

Where did the story come from?

The study was carried out by researchers from the University of London and the University of Glasgow. Funding was provided by the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care (CLAHRC). Data collection was funded by grants from the Wellcome Trust, the British Heart Foundation and the National Prevention Research Initiative.

The study was published in the peer-reviewed medical journal Archives of Disease in Childhood.

There were no conflicts of interest reported by the research team.

The UK media generally reported on this study accurately, though none of the media outlets really explains why this link may have been seen or that the study can't prove that screen time itself increases risk.

The Mail Online provided a number of figures from other sources to add context to the study findings. We are unable to comment on the accuracy of these sources. 

 

What kind of research was this?

This is a cross-sectional survey looking into association between daily screen time and risk markers for type 2 diabetes and cardiovascular disease in children aged nine and 10 years.

Type 2 diabetes and obesity are increasing in adults and children. The effect of sedentary behaviour such as watching television and using computers, known as "screen time", are a cause for concern and associations have been seen between prolonged screen time and body fatness in children.

Using data from this survey the researchers were able to identify potential risk factors, however due to the nature of this study design they would not be able to prove that one thing causes the other. The researchers say they can use their findings to design further studies to prove causation.

A randomised controlled trial would be required to prove such a link. However, a trial that randomises children to different amounts of sedentary time or physical activity and then follows them for sufficient time to observe outcomes may be neither feasible nor ethical.

 

What did the research involve?

This was a cross-sectional study known as The Child Heart and Health Study in England.

Researchers carried out a survey of primary school children aged nine and 10 years from London, Birmingham and Leicester. A single research team collected key information between October 2004 and February 2007. Some of the information recorded was as follows:

• ethnic origin (based on the ethnicity of both parents)
• socioeconomic status
• height
• weight
• skin fold measurements
• fat mass
• blood glucose and insulin levels
• insulin resistance – a measurement of how the body's cells respond to insulin
• cholesterol
• blood pressure
• pubertal status measured in girls (girls tend to start puberty earlier than boys)

On the same day as the physical measurements were taken, children completed a questionnaire asking "How many hours each day do you spend watching television or video and playing computer games?"

The children had to tick the most appropriate response, the options were:

• none
• an hour or less
• one to two hours
• two to three hours
• more than three hours

In a sub-group of children, activity was measured using a monitor worn around the waist.

When analysing the findings the researchers attempted to account for the effects of confounding factors such as socioeconomic status, physical activity and pubertal status.

 

What were the basic results?

The analysis focused on the 4,495 children (2,337 girls and 2,158 boys) who had screen time data, all physical measurements and a fasting blood sample. More than 2,000 children had physical activity data collected from the waist monitor.

The most commonly reported screen time duration was one hour or less (37%), with 18% reporting more than three hours and 4% reporting no screen time at all.

Boys were more likely to have more than three hours of screen time a day, 22% compared to 14% of girls.

Differences were seen between ethnic groups, a higher proportion of black African-Caribbean children (23%) had more than three hours of daily screen time compared with white Europeans (16%) and South Asians (16%).

Children reporting more than three hours of screen time were found to have a higher level of body fat than those with an hour or less screen time.

This was as measured by ponderal index (ponderal means related to weight – the index is a measure of kg/m3; which was on average 1.9% higher), skinfold thickness (4.5% greater), fat mass index (3.3% higher) and leptin (a hormone that controls hunger – 9.2% higher).

They also had higher levels of blood insulin and insulin resistance compared to children taking one hour or less, though there was little link with blood glucose control.

 

How did the researchers interpret the results?

The researchers conclude: "Strong graded associations between screen time, adiposity and insulin resistance suggest that reducing screen time could facilitate early T2D [type 2 diabetes] prevention. While these observations are of considerable public health interest, evidence from randomised controlled trials is needed to suggest causality."

 

Conclusion

This cross sectional study aimed to investigate the association between markers for type 2 diabetes and the amount of screen time a child has.

The study found an association between higher levels of screen time and higher body fat and insulin resistance. However, as mentioned, this type of study is not able to prove cause and effect. It is most likely not the screen time itself that is the cause of these factors, more that this could indicate a generally less healthy and more sedentary lifestyle. A similar link might be found for children who spend more time reading books instead of taking physical activity.

The researchers have tried to adjust for physical activity and socioeconomic status that could be influencing the link. However, it is possible that some confounding remains in the model or that other important factors were missed – diet being a notable possibility. It's also possible that children who reported more screen time may have had other health conditions which were not accounted for in the analysis that could have increased their risk.

Other important limitations are that the amount of screen time was self-reported and children may not have remembered or reported this accurately. The measures of body fat and blood glucose control were also one-off measurements taken at single point in time. They don't tell us that the child will go on to develop type 2 diabetes.

Nevertheless the study suggests a reduction in screen time could be beneficial in improving health and possibly reducing the risk of type 2 diabetes and other obesity-related diseases in later life.

One pressing concern is that the data gathered in the study was taken before the use of smartphones and tablets became widespread in older children. Smartphones became commonly used around 2008 to 2010 and the first tablet (the iPad) was released in 2010. So it could well be the case that screen time has now increased in older children.

With these concerns in mind it is important that children are taught to compensate for time spent "gawping at gadgets" (as the Mail puts it) with time spent being physically active.

Guidelines for children and young people recommend that to maintain a basic level of health at least 60 minutes of physical activity every day should be taken; this could be cycling, playground activities or more vigorous activity, such as running and tennis. Exercises for strong muscles and bones are recommended three days a week such as push-ups, jumping and running.

Read more advice about encouraging children to be more physically active.

Links To The Headlines

Screentime linked to greater diabetes risk among children. The Guardian, March 13 2017

Watching TV three hours a day linked to child diabetes. The Independent, March 13 2017

Children's risk of developing Type 2 diabetes soars with just three hours of screen time a day. Mail Online, March 13 2017

Kids who spend three hours a day watching telly or playing video games ‘flirting with diabetes’. The Sun, March 13 2017

Links To Science

Nightingale CM, Rudnicka AR, Donin AS, et al. Screen time is associated with adiposity and insulin resistance in children. Archives in Disease for Childhood. Published online March 13 2017

via NHS Choices: Behind the headlines More READ

Fasting diet may help regenerate a diabetic pancreas

"The pancreas can be triggered to regenerate itself through a type of fasting diet, say US researchers," BBC News reports.

Research in mice found a low-calorie diet may help in cases of type 1 and type 2 diabetes.

The pancreas is an organ that uses specialised cells known as beta cells to produce the hormone insulin, which the body uses to break down sugars in the blood (glucose).

In type 1 diabetes the pancreas stops producing insulin. In type 2 diabetes either not enough insulin is produced or cells in the body fail to respond to insulin (insulin resistance).

Mice were fed for four days on a low-calorie, low-protein and low-carbohydrate but high-fat diet, receiving half their normal daily calorie intake on day one, followed by three days of 10% of their normal calorie intake.

Researchers repeated this fast on three occasions, with 10 days of refeeding in between. They then examined the pancreas.

They found in mice modelled to have both type 1 and type 2 diabetes, insulin production was restored, insulin resistance was reduced, and beta cells could be regenerated. Early lab study involving human cell samples showed similar potential.

These are promising results, but further studies are needed to validate these findings in humans.

If you have either type 1 or type 2 diabetes, you shouldn't attempt a fasting diet without first seeking medical advice. A sudden change in your calorie intake could have unpredictable effects and lead to complications.

Where did the story come from?

The study was carried out by researchers from the University of Southern California and the Koch Institute at the Massachusetts Institute of Technology (MIT) in the US, and the IFOM FIRC Institute of Molecular Oncology in Italy.

It was funded by grants from the US National Institutes of Health (NIH) and the US National Institute on Aging (NIA).

The study was published in the peer-reviewed journal, Cell. It's available on an open access basis and is free to read online (PDF, 6.74Mb).

The UK media coverage of the research is generally accurate. BBC News provided useful advice from one of the authors, Dr Longo, who cautioned: "Do not try this [fasting] at home. This is so much more sophisticated than people realise". 

What kind of research was this?

This animal study examined whether a diet mimicking fasting cycles is able to promote the generation of new pancreatic beta cells in a mouse model of diabetes.

Beta cells are found in the pancreas. The cells' primary function is to store and release insulin in response to changes in blood glucose concentration.

In people with diabetes, the beta cells are either destroyed by the person's own immune system (type 1) or are unable to produce a sufficient amount of insulin (type 2).

Beta cells are reported to be highly sensitive to the availability of nutrients. The researchers wanted to see whether prolonged fasting and refeeding could regenerate pancreatic cells.

Animal studies like this one are useful early-stage research to help better our understanding of cellular mechanisms.

However, the human body has complex biology and we're not identical to mice, so further studies would be needed to see whether the same effects are observed in humans.

What did the research involve?

The first phase of the study involved male mice aged 10-16 weeks, some of whom had injections of a chemical to destroy their beta cells to mimic type 1 diabetes. Others were genetically bred to have type 2 diabetes, and normal mice acted as controls.

The researchers put the mice on a four-day fasting regimen consisting of a low-calorie, low-protein, low-carbohydrate and high-fat (FMD) diet.

They were fed 50% of their standard calorie intake on day one, followed by 10% of their normal calorie intake on days two to four.

At the end of the four days, the mice were fed regularly for up to 10 days to ensure they regained their body weight before the next fasting cycle. They underwent three dietary intervention cycles.

Blood glucose measurements were taken regularly. Pancreatic cell samples were taken to look at gene activity and investigate whether there were any changes.

The second phase of the study involved analysing human pancreatic cell samples collected from people with type 1 diabetes. 

Researchers also recruited healthy human adult volunteers without a history of diabetes, who underwent three cycles of a similar five-day fasting regimen. The blood samples from these people were applied to the cultured pancreatic human cells.

What were the basic results?

In the mouse model of type 2 diabetes, after the FMD cycles insulin secretion was restored and insulin resistance was reduced. The FMD cycles seemed to induce beta cell regeneration.

In the mouse model of type 1 diabetes, FMD cycles were able to reduce inflammation and promote changes in the levels of cytokine proteins, which may indicate the restoration of insulin secretion. There was an increase in the proliferation and number of beta cells generating insulin.

The results in the human cell samples suggested similar findings to those seen in mice. FMD cycles – that is, in blood samples from fasted individuals applied to human pancreatic cells in the laboratory – may be able to promote reprogramming of cell lineages and generate insulin in pancreatic islet cells.

How did the researchers interpret the results?

The researchers concluded that, "These results indicate that an FMD promotes the reprogramming of pancreatic cells to restore insulin generation in islets from T1D [type 1 diabetes] patients and reverse both T1D and T2D [type 2 diabetes] phenotypes in mouse models." 

Conclusion

This animal study examined whether a diet mimicking fasting cycles would be able to promote the generation of new insulin-producing pancreatic beta cells in a mouse model of diabetes.

Overall, researchers found in mice models of both type 1 and type 2 diabetes, insulin secretion was restored and insulin resistance and beta cells could be regenerated or have their function restored. Very early laboratory study on human cell samples suggested similar potential.

These results show promise, but further research is needed to validate these findings in humans.

Professor Anne Cooke, professor of immunology at the University of Cambridge, commented: "This is good science and does give promise for the future treatment of diabetes, but we need further studies to see whether this works in people as well as it has in mice."

Don't suddenly try fasting, or any other radical change to your diet, without first consulting the doctor in charge of your care. Sudden changes to your diet could cause complications.

Links To The Headlines

Fasting diet 'regenerates diabetic pancreas'. BBC News, February 24 2017

Hope for millions of diabetics as condition could be reversed with yo-yo starvation diet. Daily Mirror, February 23 2017

Fasting diet could prove the cure for type 2 diabetes. The Times, February 24 2017 (subscription required)

Links To Science

Cheng C, Villani V, Buono R, et al. Fasting-Mimicking Diet Promotes Ngn3-Driven β-Cell Regeneration to Reverse Diabetes. Cell. Published online February 23 2017

via NHS Choices: Behind the headlines More READ

Diabetes could be a warning sign of pancreatic cancer

"Experts have revealed the onset of diabetes, or existing diabetes getting much worse could be a sign of hidden pancreatic cancer," reports The Daily Express.

The media reports follow a press release of a study presented at the European Cancer Congress (ECCO) yesterday. The research analysed nearly a million people with type 2 diabetes in Belgium and Italy, some of whom went on to be diagnosed with pancreatic cancer.

The recent onset of diabetes appeared to be a possible warning sign of pancreatic cancer, with 25% of cases in Belgium and 18% in Italy being diagnosed within three months of a diabetes diagnosis. Faster progression of diabetes (where patients needed insulin or other more intensive treatments sooner) was also associated with a greater chance of being diagnosed with pancreatic cancer.

Pancreatic cancer is rare and often has a poor outcome, partly because it is difficult to detect at an early stage.

However, it's important to put these findings in context. Diabetes has previously been linked with pancreatic cancer, though it is unclear why. It could be that diabetes increases the risk of pancreatic cancer. What is probably more likely is that rapid onset or progression of diabetes could be a symptom of the cancer itself.

Diabetes is fairly common in the UK, with around 4 million cases, while pancreatic cancer remains very rare. Just because you have diabetes does not mean you will go on to get pancreatic cancer.

However, if you are concerned that you may have diabetes or that your diabetes is poorly controlled, you should talk to your GP.

There are also steps you can take to reduce your risk of developing diabetes.

Where did the story come from?

The study was carried out by researchers from the International Prevention Research Institute in Lyon, France. The study has not yet been published in a journal but was presented at the European Cancer Congress held in Amsterdam. The findings come from the press release.

Funding was provided by Sanofi, a French pharmaceutical company. The authors declare the sponsor had no influence on the study design, conduct, analysis and reporting.

This has been reported widely in the UK media, though not always accurately. The Mail Online claims the researchers "analysed nearly a million type 2 diabetics in Italy and Belgium who had been told they had pancreatic cancer" however this was the number of people in the database with diabetes. Only 2,757 people had been diagnosed with pancreatic cancer.

Moreover, The Daily Telegraph reports "50 per cent of patients diagnosed with pancreatic cancer had been diagnosed with type 2 diabetes the previous year". This is rather misleading and suggests 50% of all people with pancreatic cancer also have diabetes.

But this study only looked at people with diabetes. Of those who developed pancreatic cancer, half had received their diabetes diagnosis in the past year. The overall proportion of all people with pancreatic cancer who also have diabetes in the population is unknown.

What kind of research was this?

This was a retrospective cohort study looking at the association between type 2 diabetes and the diagnosis of pancreatic cancer.

The study is currently only available as a published abstract and was presented at the European Cancer Congress with an accompanying press release. A full study publication is not available so we can't fully critique the methods and analysis.

Pancreatic cancer has a notoriously poor prognosis as it is often hard to diagnose at an early stage due to a lack of symptoms or non-specific symptoms. Individual outcomes vary, but generally only 1% of all people diagnosed with pancreatic cancer live for more than 10 years after their diagnosis.

Diabetes has already been linked as a possible risk factor for pancreatic cancer, but in what context is uncertain. However, onset of diabetes or rapid deterioration of current diabetes could be a possible marker for early pancreatic cancer so could potentially aid earlier diagnosis.

What did the research involve?

The researchers used a prescription database (the Inter Mutualist Agency AIM-IMA) to identify 368,377 people receiving treatment for type 2 diabetes patients in Belgium between 2008 and 2013. They also identified 456,311 being treated in Lombardy, Italy, between 2008 and 2012.

These data were linked to pancreatic cancer data from the Belgium Cancer Registry and hospital discharge databases in Lombardy.

The rates of pancreatic cancer were analysed in association with time of first prescription of diabetes drugs, and use of different diabetes treatments.

What were the basic results?

In Belgium, 885 of 368,377 people with diabetes had pancreatic cancer. In Lombardy, 1,872 of 456,311 people with diabetes had pancreatic cancer.

Among all those with pancreatic cancer in the two regions, 50% had been diagnosed within one year of being diagnosed with type 2 diabetes.

In Belgium, 25% of pancreatic cancer cases were diagnosed within 90 days and in Lombardy 18% were diagnosed within 90 days.

When considering treatment, the researchers generally found that switching to more intensive diabetes treatments was also linked with a greater risk of pancreatic cancer diagnosis:

• People who switched from oral diabetes drugs to more intensive treatment of incretin-based therapy (injected drugs that help the body produce more insulin) had 3.3 times the risk (95% confidence interval [CI] 2.0 to 5.5) of cancer diagnosis in the following three months.
• This decreased to around a two-fold risk for 3 to 6 months after the first prescription of incretin drugs (hazard ratio [HR] 2.3, 95% CI 1.2 to 4.7) and again for 6 to 12 months after the first prescription (HR 2.1, 95% CI 1.2 to 3.9).
• Switch from oral diabetes drugs or incretin to insulin injections was also linked with increased risk of pancreatic cancer (HR 11.9, 95% CI 10.4 to 13.6).
• When comparing those who developed pancreatic cancer with those who remained cancer-free, switching from oral diabetes drugs to incretin or insulin injections happened sooner after diabetes diagnosis in those who developed cancer: median 372 days to switch to incretins and 315 days to switch to insulin in those who developed cancer versus median 594 days to switch to incretins and 437 days to switch to insulin.

How did the researchers interpret the results?

The lead researcher commented: "There is currently no good, non-invasive method for detecting pancreatic cancer that is not yet showing any visible signs or symptoms. We hope that our results will encourage the search for blood markers indicating the presence of pancreatic cancer, which could guide decisions to perform a confirmation examination like endoscopy."

Conclusion

This study uses a large prescription database to investigate the link between diabetes and pancreatic cancer, looking at the timing of first diabetes prescription and change in drugs prescribed.

Among people with type 2 diabetes, diagnosis of pancreatic cancer was linked with recent onset of diabetes or rapidly deteriorating diabetes. This suggests these could both be potential warning signs of hidden pancreatic cancer and indicate the need for more investigations.

While diabetes has previously been linked with pancreatic cancer, the nature of the cause and effect relationship remains unclear. It could be that diabetes increases risk of the cancer, or it could be that recent onset or deterioration of diabetes is a symptom of the cancer.

It had also previously been thought that incretin therapies could promote pancreatic cancer. However, it could be that incretin therapies and insulin therapies are often prescribed sooner in patients who have undiagnosed pancreatic cancer.

As the authors make clear, it is probably pancreatic cancer that causes deterioration of diabetes.

A limitation of this study is that it was carried out in two specific areas in Europe. Sociodemographic variations in diabetes or cancer prevalence, medical care or risk factors may mean the results are not fully applicable to the UK.

The findings are also based on a prescription database, so only look at raw data on numbers. The researchers haven't delved further into the nature of the individual diabetes and cancer diagnoses, investigations and treatment.

These are early findings presented at a conference. A full, published study is not available so it is not possible to analyse the methods and possible implications further.

It's not possible to say whether the findings could lead to more in-depth investigation of people with newly diagnosed or rapidly progressing diabetes, or whether this could make earlier pancreatic cancer diagnosis and improved survival rates possible.

Links To The Headlines

Pancreatic cancer symptoms: Diabetes could be a warning sign for deadly disease. The Daily Express, January 30 2017

Having diabetes is a warning sign of one of the deadliest forms of CANCER, shocking study finds. Mail Online, January 30 2017

Diabetes could be a warning sign of cancer, new study suggests. The Daily Telegraph, January 30 2017

via NHS Choices: Behind the headlines More READ

Urine test could reveal if your diet is a threat to your health

"A urine test that can reveal how healthy your meals are has been developed by UK scientists," BBC News reports.

Researchers wanted to see if they could help crack one of the biggest problems confronting people trying to carry out studies into diet and health. Namely, that the most widely used method to assess diet – self-reporting – is notoriously unreliable.

Study after study has found that most people are prone to under-reporting the amount of unhealthy food they eat while over-reporting the amount of healthy food.

In this small study, on four separate occasions, 20 participants consumed four different diets which were assessed as ranging from very healthy (in terms of agreeing with international guidelines) to unhealthy.

Urine samples were tested for substances known to be associated with certain types of dietary patterns (metabolic profiles).

The researchers found that urine tests were in fact robust enough to identify dietary patterns in the participants – the levels of 19 substances (metabolites) were significantly higher in the healthiest of the four diets compared with the unhealthiest.

As this study had a very small sample size, it's likely that more research will be needed to verify the findings, before considering how best urine tests could be adopted as a dietary tool for health services.

If you are looking to make your diet more healthy, you may want to start keeping a food diary – where you record exactly what you eat, rather than relying on your unreliable memory.

 

Where did the story come from?

The study was carried out by researchers from a range of institutions in the UK, US and Denmark including Imperial College London, Northwestern University and the University of Southern Denmark.

It was funded by the UK National Institute for Health Research and the UK Medical Research Council. Some of the researchers have received payments the large food and consumer goods manufactures Unilever and Nestlé.

The study was published in the peer-reviewed scientific journal Lancet Diabetes and Endocrinology. It is available on an open-access basis so is free to read online.

Both BBC News and the Mail Online's reporting of the study was accurate.

 

What kind of research was this?

This was a randomised-controlled crossover trial which wanted to investigate whether dietary intake in individuals could be revealed and measured using urine samples.

Diet has a part to play in the increase in risk of non-communicable (non-infectious) diseases such as type 2 diabetes and heart disease. Current dietary tools aren't always able to assess the effect of policy change on dietary behaviour in populations. The researchers wanted to see if urine metabolic profiles could reflect dietary intake and offered an alternative method to do this.

Randomised trials are one of the best ways to determine the effects of an intervention. Crossover trials are when participants act as their own control and receive the different tested interventions in random order, in this case the different diets. They are often used when the sample size is small – as was the case with this trial – as a way to boost the numbers for comparison.

In this study, it wasn't possible to blind the participants from the dietary intervention but the individuals analysing the data were prevented from knowing the randomisation order.

 

What did the research involve?

Between August 2013 and May 2014, healthy volunteers (aged 21-65) with a body mass index (BMI) between 20–35kg/m2 were recruited for this study from a database at the UK National Institute for Health Research (NIHR)/ Wellcome Trust Imperial Clinical Research Facility (CRF).

Of a potential 300 recruited by invitation letter, only 26 were eligible and attended a health screening, 20 of these people were randomised in the trial.

The trial aimed to assess four dietary patterns which varied in a stepwise manner in their compliance with World Health Organization (WHO) healthy eating guidelines. Essentially the diets gradually increased in content of fruits, vegetables, whole grains, and dietary fibre, while decreasing in their content of fats, sugars, and salt.

Participants were asked to attend four inpatient stays of 72 hours (separated by at least five days) during which they were given one of the four dietary interventions. The order of the diets was randomised across each study visit.

Adherence to the interventions was closely monitored with food weighed immediately before and after being given to the participants. Additionally, participants were only allowed to engage in very light physical activity – this was also closely monitored.

During the inpatient stay, urine was collected three times every day: morning collection (0900-1300h), afternoon collection (1300-1800h), and an evening and overnight collection (1800-0900h).

Of the 20 participants, 19 completed the full trial and their urine samples were assessed for metabolic profiles using proton nuclear magnetic resonance (1H-NMR) spectroscopy. This is a process to analyse the chemical compositions of a substance.

 

What were the basic results?

Overall, the urine metabolic profiles were distinct enough to assess each of the diets consumed. The metabolite concentrations translated to specific components of each diet.

The results were interesting, for example, the 1H-NMR analysis showed that the presence of 19 metabolites were in significantly higher concentrations after consumption of diet 1 – which had the greatest agreement with WHO dietary recommendations – compared to diet 4 – the highest risk diet with the least agreement to recommendations.

The analysis also showed detailed variability in metabolite concentrations between the participants.

 

How did the researchers interpret the results?

The researchers concluded: "Urinary metabolite models developed in a highly controlled environment can classify groups of free living people into consumers of diets associated with lower or higher non-communicable disease risk on the basis of multivariate metabolite patterns.

"This approach enables objective monitoring of dietary patterns in population settings and enhances the validity of dietary reporting."

 

Conclusion

This well-designed, randomised crossover trial investigated whether the dietary intake in individuals could be revealed and measured using urine samples and found that it is possible.

Urine analysis using 1H-NMR spectroscopy was distinct enough to distinguish "healthier" and higher risk diets by looking at the metabolites present in the urine.

The researchers hope that this study offers a method which could be used to assess adherence to healthy eating programmes, and potentially be used as a screening tool to identify and monitor individuals at risk of obesity and non-communicable diseases.

These tests have the potential to be of benefit as a research tool. Some studies have suggested that as many as 88% of people record their dietary intake inaccurately, so an independent objective measuring tool, could be very helpful.

Although this study sounds promising, the study sample was small with only 19 participants completing the full trial. Even in the context of a crossover trial this is very small and may not give reliable enough results from which to draw firm conclusions.

Further research with a much larger sample size may be required to see that urine metabolite testing is accurate enough to distinguish dietary patterns and then be used by researchers and health services.

If you are trying to improve your diet, and possibly lose weight, then following the NHS Choices Weight Loss Plan may help. This provides downloadable "diet diary" sheets as well as suggestions for healthy meal choices.

Links To The Headlines

Urine test reveals what you really eat. BBC News, January 13 2017

Five-minute test that says if your diet's healthy by analysing biological markers created by the breakdown of meat, fruit and vegetables. Mail Online, January 13 2017

Links To Science

Garcia-Perez I, Posma JM, Gibson R, et al. Objective assessment of dietary patterns by use of metabolic phenotyping: a randomised, controlled, crossover trial. The Lancet – Diabetes and Endocrinology. Published online January 12 2017

via NHS Choices: Behind the headlines More READ

Claim high-fat diets can prevent diabetes 'unproven'

"Diets laden with butter, cream and cheese 'can help combat surge in type 2 diabetes'," the Mail Online reports.

But the study it reports on only followed a small group of men for 12 weeks – not long enough to determine whether the diet would prevent diabetes or other chronic diseases.

The study involved 38 overweight to obese men randomised to one of two strictly controlled diets containing the same amount of calories, which the body "burns" to create energy.

In the first group, the energy mainly came from carbohydrates (53% of total calorie intake), while the energy mainly came from fats (73% of total calorie intake) in the second group.

Men in both groups lost weight and body fat after 12 weeks on the diets. There were only minor differences in certain blood sugar and cholesterol markers – nothing you could draw any conclusions from.

The main problem with this trial is it is so small, and it looked only at short-term effects.

You can't conclude anything from these results about the longer-term effects the diet would have on diabetes and cardiovascular disease.

An important fact not mentioned in the reporting of the study is both of the diets involved eating fewer calories than the men had previously consumed.

This reinforces the fact there is no magic bullet to weight loss – simply eat less and move more.

The study certainly doesn't give the green light to eating as much fat as you like. But healthy unsaturated fats should be included as part of a balanced diet.

Where did the story come from?

The study was carried out by researchers from the University of Bergen in Norway, and was published in the peer-reviewed American Journal of Clinical Nutrition.

It was funded by the Western Norway Regional Health Authority, Meltzerfondet, Bergen Medical Research Foundation, and the University of Bergen. Several companies provided products used in the study.

The Mail Online's reporting of the study was poor. In the final paragraph of the study, the researchers warn about trying to extrapolate their short-term results to longer-term effects on metabolic and cardiovascular disease risk. Yet this is precisely what the Mail has done.

It's very difficult to see how the Mail concluded a high-fat diet "can combat [the] surge in type 2 diabetes". The reduction in fasting blood sugar was in fact seen in the low-fat group, not the high-fat one.

And even then there was little difference seen between the groups for other markers – the study categorically did not find one of these diets was better than the other.

What kind of research was this?

This randomised controlled trial (RCT) aimed to investigate the theory that consuming fats or carbohydrates would have different effects on the amount of fat around body organs and on markers of metabolic syndrome. 

Metabolic syndrome is a collection of signs and symptoms – high blood pressure, high cholesterol, poor blood sugar control and obesity – that put a person at increased risk of cardiovascular disease and diabetes.

It's thought different dietary components could make some people more likely to develop the syndrome.

A randomised controlled trial is the best way of investigating the effects of an intervention.

But the difficulty with a randomised controlled trial assessing diet is that because of the practicalities of running the trials, they often include small numbers of people assessed on a short-term basis.

This means the results of such studies can't lead to sweeping conclusions on a population level.

What did the researchers do?

The trial recruited 46 overweight to obese men aged 30 to 50 with a body mass index (BMI) over 29 via a newspaper advertisement.

Researchers excluded men with serious illness and those taking regular medication or who had recently been trying to lose weight.

The men were randomised to follow 12 weeks of one of two diets:

• very high-fat, low-carbohydrate (VHFLC) diet with 73% of energy from fat and 10% from carbohydrate
• low-fat, high-carbohydrate (LFHC) diet with 30% of energy from fat and 53% from carbohydrate

The two diets provided identical daily energy intake (8,750 kJ/day), with 17% from protein. Both diets followed a low glycaemic index (GI) pattern, meaning they wouldn't cause a rapid rise in blood glucose levels after eating.

Both groups were told to consume more than 500g of fruit and vegetables a day and eat fish twice a week, and were given standardised supplies of butter, coconut oil and sugar substitutes.

Each group was also given recipe booklets for their specific diet and attended a course prior to the trial to ensure they understood the diet.

Each month the men were asked to keep five-day food records and weigh out their food on a daily basis.

The men were asked to keep their physical activity the same, were questioned about their ability to follow a diet strictly, and told about the importance of accuracy and honesty during the trial.

The researchers analysed blood samples to look at fat levels and blood sugar, examined the men's respiratory function, and used CT scanners to assess body composition.

What did they find?

After various drop-outs, only 38 of the original 46 men were available for analysis – just 18 in the LFHC group and 20 in the VHFLC group.

Body weight dropped by about 11-12kg, or 3.6 BMI points in both groups over the 12-week period.

Total abdominal fat and fat around the organs decreased by roughly 20-30% in both groups. Waist circumference decreased by 11-13cm. There were no significant differences between the groups.

Fasting blood sugar only reduced in the LFHC group, but there were no other between-group differences for other measures of blood sugar control, such as insulin.

Levels of one type of fat (triglycerides) decreased in both groups. Low-density ("bad") cholesterol decreased only in the LFHC group, but high-density ("good") cholesterol increased only in the VHFLC group.

Improvements were noted to occur within the first eight weeks in the VHFLC group, but were more gradual in the LFHC group.

What did the researchers conclude?

The researchers concluded that, "Consuming energy primarily as carbohydrate or fat for three months did not differentially influence [organ] fat and metabolic syndrome in a low-processed, lower-glycaemic dietary context.

"Our data do not support the idea that dietary fat per se promotes [body fat] and cardiometabolic syndrome in humans." 

Conclusions

This small trial aimed to see whether there is a difference between strictly controlled low-GI diets that contain the same amount of energy, but are either predominantly fat or carbohydrate based.

Overall, researchers found the diets caused both weight and fat reduction, with little difference between the two – with the exception of minor differences in certain blood sugar and cholesterol markers, the significance of which is difficult to interpret. These could just be down to chance.

The researchers were careful to control the diets and other lifestyle aspects to try to ensure any observed effects were only coming from the diets.

However, the trial had a couple of important limitations. For one, it was very small to start with, even before losing an extra eight to follow-up.

As the researchers acknowledged, the study may not have had sufficient numbers to reliably detect differences in outcomes between the groups.

The groups also included a specific group of overweight to obese men, so the effects in these people may not be comparable with other populations.

Most importantly, short-term measures of weight, blood sugar and body fat at three months tell you nothing about the possible longer-term effects.

This means you can't conclude anything about a person's risk of diabetes or cardiovascular disease in the longer term.

Little can be concluded from this relatively brief, small study. It certainly doesn't change our current understanding about diet and health.

The best way to lose weight or maintain a normal weight and reduce your risk of disease is to follow current healthy eating and exercise guidelines. You should aim to eat balanced amounts of carbohydrate, protein and fat.

Links To The Headlines

Fat is GOOD for you! Diets laden with butter, cream and CHEESE 'can help combat surge in Type 2 diabetes'. Mail Online, December 11 2016

Links To Science

Veum VL, Laupsa-Borge J, Eng Ø, et al. Visceral adiposity and metabolic syndrome after very high–fat and low-fat isocaloric diets: a randomized controlled trial. The American Journal of Clinical Nutrition. Published online November 30 2016

via NHS Choices: Behind the headlines More READ