Thursday, 27 July 2017
Wednesday, 26 July 2017
Magnesium is everywhere – it does not occur free in nature, only in combination with other elements, but it is the eighth most abundant chemical element in the Earth’s crust and the third most abundant element in seawater; it is even the ninth most abundant in the Milky Way. In the human body, magnesium is the fourth most abundant ion and the eleventh most abundant element by mass, being stored in bones, muscles, and soft tissues.
Magnesium is fundamental for health: it is essential to all cells and to the function of hundreds of enzymes, including enzymes that synthesize DNA and RNA, and enzymes involved in cellular energy metabolism, many of which are vital. Magnesium is involved in virtually every major metabolic and biochemical process in our cells and it plays a critical role in the physiology of basically every single organ.
Low plasma levels of magnesium are common and are mostly due to poor dietary intake, which has lowered significantly in the last decades. Magnesium can be found in high quantities in foods containing dietary fiber, including green leafy vegetables, legumes, nuts, seeds, and whole grains. But although magnesium is widely distributed in vegetable and animal foods, some types of food processing can lower magnesium content up to 90%. Also, the soil used for conventional agriculture is becoming increasingly deprived of essential minerals. In the last 60 years, the magnesium content in fruit and vegetables has decreased by around 20 to 30%.
Symptomatic magnesium deficiency due to low dietary intake in healthy people is not very frequent, but a consistently poor dietary supply of magnesium has insidious effects. Magnesium deficiency alters biochemical pathways and increases the risk of a wide range of diseases over time, namely hypertension and cardiovascular diseases, metabolic diseases, osteoporosis, and migraine headaches, for example.
In the brain, magnesium is an important regulator of neurotransmitter signaling, particularly glutamate and GABA, the main neurotransmitters by modulating the activation of NMDA glutamate receptors and GABAA receptors. It also contributes to the maintenance of adequate calcium levels in the cell through the regulation of calcium channels’ activity.
These physiological roles make magnesium an essential element in important neuronal processes. Magnesium participates in the mechanisms of synaptic transmission, neuronal plasticity, and consequently, learning and memory. Accordingly, increased levels of magnesium in the brain have been shown to promote multiple mechanisms of synaptic plasticity that enhance different forms of learning and memory, and delay age-related cognitive decline. Increased levels of magnesium in the brain have also been linked to an increased proliferation of neural stem cells, indicating that it may promote the generation of new neurons (neurogenesis) in adulthood. This is an important feature because neurogenesis is a key mechanism in the brain’s structural and functional adaptability, in cognitive flexibility, and in mood regulation.
Magnesium supplementation has also been shown to modulate the neuroendocrine system and to improve sleep quality by promoting slow wave (deep) sleep, which, among many other functions, is also important for cognition and memory consolidation.
Furthermore, magnesium may enhance the beneficial effects of exercise in the brain, since it has been shown to increase the availability of glucose in the blood, muscle, and brain, and diminish the accumulation of lactate in the blood and muscles during exercise.
But just as increasing magnesium levels can be beneficial, magnesium deficiency can have serious harmful effects.
Magnesium has important roles in the regulation of oxidative stress, inflammatory processes and modulation of brain blood flow. In circumstances of magnesium deficiency, all of these functions can potentially be dysregulated, laying ground for neurological disorders. Also, in a context of low magnesium availability in the brain, NMDA glutamate receptors, which are excitatory, may become excessively activated, and GABAA receptors, which are inhibitory, may become insufficiently activated; this can lead to neuronal hyperactivity and to a condition known as glutamate excitotoxicity. This causes an excessive accumulation of calcium in neurons, which in turn leads to the production of toxic reactive oxygen species and, ultimately, to neuronal cell death.
Magnesium deficiency has been associated with several neurological and psychiatric diseases, including migraine, epilepsy, depression, schizophrenia, bipolar disorder, stress, and neurodegenerative diseases. Magnesium supplementation has shown beneficial effects on many of these conditions, as well as in post-stroke, post-traumatic brain injury, and post-spinal cord injury therapies. This therapeutic action is likely due to its action in blocking NMDA glutamate receptors and decreasing excitotoxicity, in reducing oxidative stress and inflammation, and in increasing blood flow to the brain, all of which are determinant in the outcome of these conditions.
There are multiple benefits to be obtained from magnesium, both from a health promotion, and from a disease prevention and management perspective. The recommended daily intake of magnesium is of 320mg for females and 420mg for males. Too much magnesium from food sources has no associated health risks in healthy individuals because the kidneys readily eliminate the excess. However, there is a recommended upper intake level for supplemental magnesium, since it can cause gastrointestinal side effects. So, keep it below 350mg/day.
Chen HY, et al (2014). Magnesium enhances exercise performance via increasing glucose availability in the blood, muscle, and brain during exercise. PLoS One, 9(1):e85486. doi: 10.1371/journal.pone.0085486
de Baaij JH, et al (2015). Magnesium in man: implications for health and disease. Physiol Rev, 95(1):1-46. doi: 10.1152/physrev.00012.2014
Held K, et al (2002). Oral Mg(2+) supplementation reverses age-related neuroendocrine and sleep EEG changes in humans. Pharmacopsychiatry, 35(4):135-43. doi: 10.1016/j.pbb.2004.01.006
Jia S, et al (2016). Elevation of Brain Magnesium Potentiates Neural Stem Cell Proliferation in the Hippocampus of Young and Aged Mice. J Cell Physiol, 231(9):1903-12. doi: 10.1002/jcp.25306
National Institutes of Health, Office of Dietary Supplements. Magnesium Fact Sheet for Health Professionals
Slutsky I, et al (2010). Enhancement of learning and memory by elevating brain magnesium. Neuron. 2010 Jan 28;65(2):165-77. doi: 10.1016/j.neuron.2009.12.026Read More Here..
Statement by UNICEF Executive Director, Anthony Lake, WFP Executive Director, David Beasley and WHO Director-General, Dr. Tedros Adhanom Ghebreyesus, following their joint visit to Yemen
Tuesday, 25 July 2017
Monday, 24 July 2017
The use of smart drugs is becoming “trendy”. Lots of people are taking various substances regularly, many others try them from time to time. The idea of enhancing the brain’s ability, or tapping into its unused reservoir is definitely sexy, and many people are actively looking for information on this subject.
The shortage of scientifically verified information is exactly the reason I’m writing this article. Although thousand of publications on “smart drugs”, “cognitive enhancers”, and “nootropics” etc. can be found online, the overwhelming majority of claims are unsubstantiated or unashamedly commercialized. This means that the info you come across mostly consists of descriptions of personal opinions or experiences, or compilations of facts published elsewhere, or just articles from popular media where people can write whatever they want.
Multiple websites publish all kind of rubbish just to convince you to buy yet another wonderfully effective smart drug. Few people make an effort to refer to their sources of information, not to mention to present scientific and statistical data backing their claims. This is particularly enigmatic when these articles provide recipes for various drug combinations and claim the superiority of some of these combinations/compounds over the others. However, even scientific data on the subject is rather incomplete. Many studies were done using only a small number of participants, or in the absence of any reasonable controls. On their own, studies of such kind are of little, if any, value.
Fortunately, several systematic reviews and meta-analyses on the use of nootropics were published in the last couple of years. Systematic reviews and meta-analyses combine data from multiple individual studies, thus making the data statistically significant. This is a better way of assessing the efficacy of different drugs in the general, healthy population, and these are the publications that I will mostly use as reference points in this article.
How to prove that a smart drug is really smart?
Smart drugs (e.g., nootropics and cognitive enhancers) are defined as substances that improve cognitive function, particularly executive functions, memory, creativity, or motivation, in healthy individuals. The last bit is important: there are many drugs that were specifically developed to enhance brain functions in people with various cognitive disorders or deficits. Such drugs won’t necessarily smarten up healthy people, and when they do, they are not necessarily safe. Nootropics may come in many forms, from classical pharmaceutics in the form of pills to herbal supplements and “functional foods”.
There are only few smart drugs that are proven to improve some aspects of cognition. Proving that a compound has the properties of a nootropic is not a simple task. There is no straightforward way of measuring whatever cognitive enhancement you may experience once the pill is taken. The drug may indeed work and visibly increase your productivity. But it may also simply improve your mood if you anticipate a positive effect. On top of this, any given drug may work for some people and not work for others. Furthermore, the use of any drug is associated with potential side effects (e.g., headaches) that might eliminate its advantages in productivity and creativity. If the changes in productivity can be measured using some tests, creativity still remains something arguably impossible to quantify.
How smart drugs work?
There are several mechanisms that can be involved in the functioning of smart drugs. Some drugs can increase the blood flow (and thus oxygen supply) to the brain. Others can accelerate neuronal communication through increased release of certain neuromediators or through agonistic effects on the receptors of these neuromediators. Some compounds can serve as biochemical precursors of neuromediators, others may prevent oxidative damage to brain cells or provide them with a source of energy. Some of these changes can be achieved quickly making the drugs work almost instantly. Others, such as amendment/prevention of neuronal damage, manifest themselves only after prolonged use of the drug, thus making any changes in cognitive functions not so fast and not so obvious (although they can still be substantial).
Short overview of most popular nootropics
Amphetamines are a class of pharmaceuticals that include adderall, dextroamphetamine, and lisdexamphetamine. The drugs were developed to treat people with ADHD (attention deficit hyperactivity disorder) and this is where their effects are the most prominent. The drugs were also demonstrated to improve episodic memory, working memory, and some aspects of attention in the general population. At low doses they improve memory consolidation, recall of information, and motivation to perform tasks that require high degree of attention. Ritalin is structurally different from amphetamines and works through different mechanisms, although produces similar effects. Both amphetamines and ritalin improve cognitive functions, albeit only at lower doses. At high doses they stimulate other neural pathways not involved in learning that effectively cancel their positive effects on cognition.
Wakefulness-promoting agents, such as modafinil and armodafinil, increase alertness, counteract fatigue, and increase productivity and motivation. Modafinil is praised for its ability to improve reaction time, logical reasoning, and problem-solving. The drug is clinically prescribed for a number of conditions including sleep apnea, narcolepsy, and shift work sleep disorder.
Compounds from the racetam family (piracetam, oxiracetam etc.) are more extensively studied compared than the newer nootropics. Piracetam was developed back in the 1960s and has an almost perfect safety profile. Convincingly, it was shown to improve cognitive abilities, particularly in older people and those with cognitive impairment. Although piracetam is officially recognized as a nootropic, its brain-enhancing effects in healthy people are considered to be moderate. There is a number of other derivatives from this group of drugs which, allegedly, work better. A good example is phenotropil. This compound was developed in Russia where it is available as a prescription drug. It was demonstrated to have a memory enhancing effect. The drug can be used as a stimulant and enhances resistance to extreme temperatures and stress. Due to its stimulating effect, phenotropil is banned by the World Anti-Doping Agency, which means that it cannot be used by athletes intending to compete in official events.
Xanthines, such as caffeine, are some of the most commonly used compounds with nootropic effects. In particular, they increase alertness and performance levels. Caffeine is not what comes to mind when we think of nootropics, but apparently its effect is comparable to many pharmaceuticals.
L-Theanine, a chemical component of green tea, is very well studied and its effects on promoting alertness and attention are confirmed by multiple research.
When it comes to nutraceuticals and herbal supplements, recent studies appear to be contradictory. Some data do support the memory-enhancing effects of such plants as Gingko biloba, Asian ginseng, and Bacopa monnieri, but systematic reviews do not find convincing evidence of their effectiveness. It is likely that herbal supplements may work well over longer periods of time and improve cognitive abilities, but in the short term their effects are not particularly obvious. The same applies to many vitamins, such as vitamin E and B group vitamins, as well as Omega-3 fatty acids: the evidence supporting their benefits are limited at the present time.
To conclude, only few drugs are scientifically proven to be associated with moderate cognitive enhancement effects in the healthy population. Being sceptical when assessing information on smart drugs from the internet is a good idea: lots of ridiculous rubbish is published online. Most nootropics are relatively safe, but side effects are always a possibility since the response to nootropics is highly individual.
Bagot KS and Kaminer Y (2014) Efficacy of stimulants for cognitive enhancement in non-attention deficit hyperactivity disorder youth: a systematic review. Addiction 109, 547–557. doi:10.1111/add.12460
Urban KR and Gao WJ (2014) Performance enhancement at the cost of potential brain plasticity: neural ramifications of nootropic drugs in the healthy developing brain. Front. Syst. Neurosci.| doi: 10.3389/fnsys.2014.00038
Winblad B (2005) Piracetam: a review of pharmacological properties and clinical uses. CNS Drug Rev. 11, 169-182. PMID:16007238
Zvejniece L et al. (2011) Investigation into Stereoselective Pharmacological Activity of Phenotropil. Basic & Clinical Pharmacology & Toxicology 109, 407–412. doi: 10.1111/j.1742-7843.2011.00742.x
Rogers PJ (2007) Caffeine, mood and mental performance in everyday life. Nutrition Bulletin 32, 84–89. doi: 10.1111/j.1467-3010.2007.00607.x
Camfield DA et al. (2014) Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: a systematic review and meta-analysis. Nutr Rev 72, 507-522. DOI: https://doi.org/10.1111/nure.12120Read More Here..
Study found using treadmills, bikes or ellipticals while on the job didn't impair thinking skills
Source: HealthDay via Exercise and Physical Fitness New Links: MedlinePlus RSS Feed Read More Here..