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Taurine

Description

Taurine is an amino acid found throughout the body, but chiefly in nerve tissue and muscle. It is thought to help regulate heartbeat and muscle contractions, water balance, energy levels and levels of neurotransmitters in the brain. The body normally makes all the taurine that it needs, so supplements are typically not required. However, taurine is sometimes considered to be a "conditionally essential" amino acid - meaning that under certain conditions, such as physical exertion, disease or injury, the body may not be able to synthesize enough taurine to meet demands. Although newborn babies cannot synthesize taurine, healthy adults make their own out of other amino acids (using vitamin B6 in the conversion of either cysteine or methionine to taurine). The best dietary sources of taurine are protein foods such as meat, poultry, eggs, dairy, and fish. Beans and nuts, which are rich sources of protein, do not contain taurine, but they do contain methionine and cysteine (which can be made into taurine by the body).

Claims

· Increases physical endurance and reaction speed
· Increases concentration and mental alertness (stay awake)
· Improves overall feeling of well being
· Strengthens heart muscle (Congestive Heart Failure)
· Prevents Cataracts
· Reduces Blood Pressure
· Enhances water balance and nutrient uptake in muscle cells ("cell-volumizing")
· Aids hydration before/during exercise (used in sports drinks)

Theory

Taurine is the second most abundant amino acid in the muscle amino acid pool (after glutamine) - so the door is open for claims to be made for a wide variety of potential physiological and metabolic functions. Cellular depletion of taurine has been linked to developmental defects, retinal damage, immunodeficiency, impaired cellular growth and the development of a cardiomyopathy. These findings have encouraged the use of taurine in infant formula, nutritional supplements and energy promoting drinks. It is theorized that periods of stress, both physical and mental, can deplete body levels of taurine and increase overall taurine requirements. Taurine is also theorized to have "cell volumizing" effects similar to (or synergistic with) creatine, whereby it may help boost cell hydration and result in a higher rate of protein synthesis. These effects of taurine to enhance the water content of cells has been used in various sports drinks to enhance their effects in warding-off dehydration during exercise in the heat. Taurine is also considered to be a mild inhibitory neurotransmitter, with some evidence of effectiveness in treating epilepsy and other excitable brain states. This last effect (as a form of sedative) would appear to go against the primary use of taurine in energy drinks and mental performance cocktails, but the overall effect could be due more to a "balancing" effect on nerve impulses, but this has yet to be demonstrated. Finally, taurine is frequently recommended as a supplement for promoting "heart health" because of the low taurine levels observed in patients following heart attacks. In this regard, taurine appears to offer potential in the treatment of arrhythmia (abnormal heartbeat) and reducing blood pressure, but the doses are relatively high at 2-6 grams per day. Other proposed uses for taurine stimulation of immune function, treatment of cataracts, alleviation of mild depression and improvement in male fertility - though none of these is very well substantiated.

Scientific Support

For the most frequent use of taurine in dietary supplements (energy levels and mental performance), the most popular product (Red Bull Energy Drink) has a handful of studies behind it. The Red Bull mixture of taurine, caffeine and glucuronolactone has been shown to increase alertness and maintain reaction time and feelings of well-being (as the placebo group gets sleepy later into the night). These effects appear to be due to more than just the caffeine content (which is about the same as a cup of coffee at 80mg/250ml), but whether or not the effects are due to the taurine, the sugar or something else in the drink is still a question mark.

The other places that we see a lot of taurine use in supplements these days are in combination with creatine in muscle building products. Red Bull and others use taurine for its alleged effects in modulating neurotransmitter release (a theoretical effect), while other supplement companies use taurine for its effects in regulating water balance and enhancing the effects of creatine supplementation (some of the body-building companies refer to this as a muscle "volumizing" effect). The enhanced water content of muscle cells may even provide a hydration and performance benefit to endurance athletes exercising in the heat.

Taurine also has some data for benefits in treating certain forms of heart malfunction such as Congestive Heart Failure (higher doses of 2-6 grams/day over 4 weeks). This effect most likely has more to do with correcting either generalized malnutrition or an underlying metabolic dysfunction in synthesizing taurine than any actual performance effect that would transfer to healthy people (and other supplements such as Coenzyme Q10 and Carnitine have more powerful effects in this regard). There are at least three mechanisms that could account for the beneficial effect of taurine in heart health. First, taurine has actions in regulating water balance via the kidneys and may help to normalize both salt and water balance following exercise and during heart failure. Second, taurine is known to modulate nerve conduction by regulating electrolyte flux. Third, taurine appears to attenuate the actions of angiotensin II - acting somewhat like an ACE inhibitor to reduce blood pressure.

Taurine (6 grams/day) has also been shown to significantly reduce urinary norepinephrine excretion, which implies a suppression of the sympathetic nervous system. This effect could be theorized to contribute to an "anti-stress" benefit, though any direct anti-stress effects have not been specifically documented.

Safety

Taurine supplementation has been examined at levels up to several grams per day (at least 6 grams/day) with no apparent adverse side effects. A not of caution should be made regarding the growing popularity of using taurine-based energy drinks as a "mixer" for alcoholic beverages. Such concoctions are widely believed (by the users) to induce a feeling of energy and euphoria, while "counteracting" the depressive effects of alcohol (which is completely false). There have been case reports of individuals attempting to drive following consumption of alcohol mixed with energy drinks - and it needs to be emphasized that neither the taurine nor the caffeine has the ability to alleviate the intoxicant effects of the alcohol (if you're drunk, these drinks do not make you sober)!

Value

Among the popular taurine-containing energy drinks, key claims center around "feeling awake in body and mind" - certainly a valuable benefit for most people. There does appear to be an "energetic" benefit delivered to people using these drinks in situations such as long (sleep-inducing) drives and in feelings of well-being when staying up late. Whether or not taurine offers any direct performance enhancement with regard to athletic activities is debatable.

Since the body can make its own taurine under most conditions (out of B6, methionine and cysteine), the argument can be made that supplementation is unnecessary. However, taurine deficiencies have been documented in vegans (strict vegetarians) and in diabetics and sub-optimal levels have been theorized to occur in people under high levels of emotional or physical stress.

Dosage

Multi-gram doses of taurine have been used in studies of heart function (up to 6 grams per day). Smaller doses (500-1500mg/day) have been used in studies of brain function (epilepsy). Typical commercial doses found in energy drinks are generally in the range or 50-100mg.

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