Taurine Boosts Good Gut Bacteria & Short-Chain Fatty Acid Prod. | 1st Study to Show Natural Beats Synthetic Taurine

The bacteria in our guts are the latest rage in medical sciences... and taurine, especially natural taurine, may be a way to modulate them in beneficial ways.

It has been some time since the last taurine article on the SuppVersity (read all articles). There was simply a lack of interesting studies... until now, or rather until the latest study of scientists from the Zhejiang University of Technology which suggests that taurine "might be of benefit to health by inhibiting the growth of harmful bacteria, accelerating the production of SCFA and reducing LPS concentration" (Yu. 2016).

As the authors of the paper point out, taurine is a necessary amino acid that taurine plays an important role in the regulation of neuroendocrine functions and nutrition.

In previous studies, taurine was shown to improve immunity, resist oxidation, delay senility, reduce blood pressure, promote recovery from acute hepatitis, etc. (Averin. 2015; Wang. 2013; De Luca. 2015; Ito. 2012). In addition, taurine can also improve the metabolism of the nutrients and play an important role in the regulation of neuroendocrine (Cuttitta et al. 2013; Camargo et al. 2015).

You can learn more about taurine & other amino acids at the SuppVersity

Taurine Pumps Up Strength & Recovery?

Taurine Improves Insulin + Glucose Metabolism

Taurine ➲ 180% Testosterone Increase

Taurine + BCAA Work Hand in Hand

43% Reduced Performance W/ BCAAs

3g Taurine Boost Glycogen Re-synthesis Sign.

With their latest study, the Chinese scientists Haining Yu, Zhengzhao Guo, Shengrong Shen , an Weiguang Shan were now able to add yet another beneficial health effect of taurine to the previous, impressive list: taurine's effect on gut microbes and metabolism.

Food	Amount	Taurine (mg)
Cheese	3 ounces	1000
Cheese,cottage	1 cup	1700
Milk,whole	1 cup	400
Yogurt	1 cup	400
Wild game	3 ounces	600
Pork	3 ounces	540
Granola	1 cup	650
Oatmeal flakes	1 cup	500
Chocolate	1 cup	400
Meat (luncheon)	1 cup	390
Wheat germ,toasted	1/4 cup	350
Egg	1 (medium size)	350
Turkey	3 ounces	240
Duck	3 ounces	240
Chicken	3 ounces	185
Sausage	3 ounces	185
Avocado	1/2 (medium)	75
Table 1: It doesn't always have to be supplements - Taurine content of selected foods (USDA Handbook #8)

As you'd expect it for a "first of its kind" study, the researchers used a rodent model to evaluate the effects of a human equivalent dose of ~1g of taurine in BALB/C who were randomly divided into three experimental groups:

• the first group was administered saline (CK),
• the second group was administered 165 mg/kg natural taurine (NE) and
• the third group one administered 165 mg/kg synthetic taurine (CS).

With the NE and CS group, this is also one of the few studies to distinguish between "natural" and "synthetic" taurine, which is obtained from isethionic acid (2-hydroxyethanesulfonic acid) and not extracted from animal bile, usually that of the ox, and subjected to a series of purification procedures by several different methods (Gioacchini. 1995).

Figure 1: Effects of taurine on gut bacteria abundance (Yu. 2016).

To assess the effects, the gut microbiota composition in mice feces was analyzed by metagenomics technology, and the content of short-chain fatty acids (SCFA) in mice feces was detected by gas chromatography (GC), while the concentrations of lipopolysaccharide (LPS) and superoxide dismutase (SOD) were detected by a LPS ELISA kit and a SOD assay kit, respectively.

Studies Confirm: Natural and Synthetic Vitamins Can Differ in Quantity & Quality of Effects! Vitamins A-E, B's & More | read more

Is "natural taurine" the "better taurine"? In the study at hand, it seems as if this was the case. The only evidence from other studies that suggests that the source of taurine matters, however, is 1995 paper by Gioacchini et al. who developed a method to distinguish the two and may thus have a vested interest in stating that "[n]atural taurine is an essential constituent of formula milk for infants and, because of the inferior nutritional value (δ), of synthetic forms, it is important to discriminate between these and taurines derived from a natural source" (Gioacchini. 1995). Another study shows that the allergy risk for synthetic taurine appears to be elevated (Lee. 2013).

Why this is the case or what triggers any differences in the effect on the microbiome is something I cannot tell you: if the molecules were structurally different, Gioacchini et al. would after all not have had to use the 13C/12C ratio that is also used to date bones and other relicts. It could eventually be solely a question of dosage - with "inferior nutritional value" the synthetic taurine may have to be dosed much higher... as high as in most previously published human studies which generated the most impressive results with 3-6g and thus 3-6x more taurine per day than the human equivalent dose (learn more about the HED concept) of the study at hand.

As the data in Figure 1 indicates, taurine had profound effects on gut microbiota could reduce the abundance of Proteobacteria, especially Helicobacter (see Figure 1, bottom right). In that, it is interesting to see that the natural taurine ...

• had more pronounced beneficial effects on the count of good bacteroidetes and was more potent than the synthetic version when it comes to reducing proteobacteria and helicobacter, and even more intriguingly
• had opposite effects on firmicutes which make up the largest portion of the mouse and human gut microbiome, can't be described as "beneficial" or "bad" as a whole, but have been shown to be involved in energy resorption and obesity

In line with the last-mentioned increase in firmicutes is the scientists' observation that the SCFA content was increased in feces of the NE group, but not the CS group that received the synthetic taurine supplement.

Figure 2: Short-chain fatty acid (SCFA) and Activity of superoxide dismutase (SOD) levels in response to natural (NE), synthetic taurine (CS) and saline control (CK) supplementation in mice (Yu. 2016).

That's interesting, also because this change went hand in hand with a 'natural exclusive' LPS content was decreased, but similar increases in the activity of the antioxidant SOD enzyme in serum and livers of the both taurine groups.

None of the previous taurine studies declared whether the chemical they used was "natural" or "synthetic", I thus suspect that a synthetic version was used in most if not all of them - that this could make a difference is still both surprising and intriguing.

Bottom line: While it is correct that both "natural taurine and the synthetic taurine could regulate the gut micro-ecology, which might be of benefit to health by inhibiting the growth of harmful bacteria" (Yu. 2016), it is quite intriguing that only the natural taurine accelerated the production of SCFA and reducing LPS concentration, while the synthetic taurine did not.

Unfortunately, I have no studies to tell you if there's (a) a general advantage of natural over synthetic taurine (see red box, too), or (b) whether your taurine is natural or synthetic. If the previous quote (see red box) from Gioacchini et al. is accurate, though, it would appear that (a) 'natural' was superior and that (b) your taurine supplement was almost certainly nor extracted from ox-bile or another expensive natural source | Comment on Facebook!

References:

• De Luca, Annamaria, Sabata Pierno, and Diana Conte Camerino. "Taurine: the appeal of a safe amino acid for skeletal muscle disorders." Journal of translational medicine 13.1 (2015): 1.
• Gioacchini, Anna Maria, et al. "Differentiation between natural and synthetic taurine using the 13C/12C isotope ratio." Rapid communications in mass spectrometry 9.12 (1995): 1106-1108.
• Ito, Takashi, Stephen W. Schaffer, and Junichi Azuma. "The potential usefulness of taurine on diabetes mellitus and its complications." Amino acids 42.5 (2012): 1529-1539.
• Lee, Seung-Eun, et al. "A case of taurine-containing drink induced anaphylaxis." Asia Pacific Allergy 3.1 (2013): 70.
• Yu, Haining, et al. "Effects of taurine on gut microbiota and metabolism in mice." Amino acids (2016): 1-17.

3g Taurine Improve Post-Workout Glycogen Resynthesis, Protect the Testes of Doping Sinners & Battles Alzheimer's

Taurine - A useful supplement for chemical, natural athletes and even sedentary slobs who are afraid of diabetes.

Taurine, or 2-aminoethanesulfonic acid, as Wikipedia says, is an organic acid widely distributed in animal tissues. It is a major constituent of bile and can be found in the large intestine, and accounts for up to 0.1% of total human body weight. That does not sound like much, but taurine has many fundamental biological roles, such as conjugation of bile acids, antioxidation, osmoregulation, membrane stabilization, and modulation of calcium signaling. It is essential for cardiovascular function, and development and function of skeletal muscle, the retina, and the central nervous system and you were thus probably not too surprised, when you've recently read on the SuppVersity Facebook Page that taurine may help with Alzheimer's disease.

You can learn more about taurine & other amino acids at the SuppVersity

Taurine Pumps Up Strength & Recovery?

Taurine Improves Insulin + Glucose Metabolism

Taurine ➲ 180% Testosterone Increase

Taurine + BCAA Work Hand in Hand

43% Reduced Performance W/ BCAAs

BCAA Neurotransmitter Depletion

In the corresponding paper that was published only recently in the ScientificReports on Nature.com Kim et al. report that orally administered taurine via drinking water rescued the cognitive deficits in a standard rodent model of Alzheimer's (APP/PS1 mice) and brought them back up to age-matching wild-type mice.

Figure 1: Improvement in spatial and hippocampal learning behaviours in taurine-treated transgenic mice. 7-month old wild-type (Wt) and agematched APP/PS1 transgenic (Tg) male mice were orally administered water or taurine (1,000 mg/kg/day) for 6 weeks (n 5 8–10 per group). After 6 weeks, behavioural tests were administered to the 8.5-month old mice. (Left) Y-maze. Average alternation (%) of each group of mice was calculated. (Right) Passive avoidance. Average latency time in seconds for each group of mice was measured (Kim. 2014).

That's unquestionably impressive, but what's more impressive is that this is by far not the first study to report that taurine exhibits a plethora of physiological functions in the central nervous system.

But taurine gives me diarrhea! If it does try taking it with a meal that will greatly reduce the risk of having to rush to the toilette and should not reduce the physiological benefits significantly. At least for the muscular effects its unlikely that it will matter at all. For the beneficial effects on the brain, it may be necessary to achieve higher serum peak levels. In view of the fact that the rodents in the aforementioned study by Menzie et al. received the taurine in the drinking water, even this is yet unlikely. If the taurine "goes right through", though, it's certainly not going to help you ;-)

In a recent review in the scientific journal Amino Acids review, Janet Menzie et al. describe the mode of action of taurine and its clinical application in the neurological diseases: Alzheimer’s disease, Parkinson’s disease and Huntington’s disease and conclude that taurine...

"[...] functions through multiple neuroprotective mechanisms: regulation of cellular osmolarity , anti-oxidant, neuromodulator of GABAergic transmission, maintenance of calcium homeostasis, inhibition of glutamate excitotoxicity, attenuation of endoplasmic reticulum stress, modulation of mitochondrial pore permeability, downregulation of a range of proapoptotic proteins while upregulating anti-apoptotic proteins and downregulation of inflammatory mediators." (Menzie. 2014)

Moroever, Menzie et al. believe that there is "strong evidence" of the existence of a specific taurine receptor, which is activated exclusively by taurine, but not by structurally similar amino acids such as glutamate, GABA and glycine and could be responsible for many of the beneficial effects taurine exerts in the context of central nervous system disorders. More specifically existing evidence clearly suggests protective effects in Alzheimer’s, Parkinson and Huntington diseases. Three pathologies that share a number of broad mechanisms: Oxidative stress, mitochondrial dysfunction, excitotoxicity, calcium imbalance, inflammatory changes apoptosis - and *tadaa* a reduced level of (Arai. 1985; Alom. 1991; Molina. 1997).

Enough of the health stuff, what about the post-workout goodness?

I know, as long as we are healthy we don't really care about debilitating central nervous system disorders... well, ok. I will spare you my moral pointing finger and get straight to the similarly unsurprising results of a recent study from the University of Tokyo. A study which clearly indicates that the provision of taurine after workouts can lead to a significant enhancement of the already elevated glycogen synthesis after your workouts.

Figure 2: Muscle and liver glycogen and serum free fatty acids (FFA) before and after the workout (Takahashi. 2014).

In two rodent studies, the Japanese researchers tested whether the oral administered of taurine  at a dosage of 0.5 g/kg body weight (for human beings that's 0.04g/kg or approximately 3g total | the SuppVersity suggested dose from previous articles, by the way) immediately after treadmill running at 25 m/ min for 90 min would alter the metabolic response and glycogen synthesis after workouts when it was (A) administered alone or (B) as part of a glucose solution containing taurine and glucose at a ratio of 1:2 - in this case 0.5g/kg taurine and 1.0g/kg glucose.

Figure 3: AUC for glucose after for 60min and 120min after the ingestion of the taurine + glucose solution. As the data indicates taurine helped to "clear" the sugar from the blood stream (Takahashi. 2014).

As the scientists point out, their "results show that post-exercise taurine administration enhances glycogen repletion in skeletal muscle" (Takahashi. 2014). The underling cause, however, is still speculative. Takahashi et al. believe that it is triggered by

1. 

   Figure 4: Changes in general oxidative damage (TBARs), protein damage and exercise performance in response to taurine vs. placebo vs. bet alanine supplementation; expressed relative to untrained control (Dawson. 2002).

   an acceleration of glucose uptake, and
2. an increase in fat oxidation

of which the latter will have a carbohydrate sparing effect and will thus leave a higher amount of carbs for glycogen repletion. In conjunction with previously established benefits of taurine, such as

• the attenuation of exercise-induced DNA damage during workouts (young men | Zhang. 2004),
• the amelioration of cytotoxic (cell damaging) effects of exercise (rodents | Dawson. 2002),
• an increase in exercise performance (specifically endurance ex. | Dawson. 2002; Miyazaki. 2004),
• additional effects on the benefits of BCAA intake for the delayed-onset muscle soreness and muscle damage induced by high-intensity eccentric exercise (Ra. 2013),
• an improvement in osmoregulation (water balance) of the muscle (Cuisinier. 2002), and
• decreases in oxidative stress during eccentric exercises (Silva. 2011)

The optimal dosing for performance increments, by the way, is between 1.2-6.0g for 2 weeks (other timing has not been tested, so it's possible that one week will suffice, too). That's at least what the only hitherto published study that investigated the effects of different doses of taurine as a means to improve the endurance performance (Miyazaki. 2004). If you want the nutrient partitioning effects, though, you would have to consume CHO + taurine after the workout - 3g of taurine should suffice. Judged by the hitherto published studies this should automatically help you to increase your workout performance after 2 weeks (the beneficial effects will, just as it is the case for creatine, accumulate until the levels are saturated).

And there are more benefits - health benefits, for juicers and non-juicers

The former, i.e. the juicers will probably be happy to hear that taurine does not just have liver protective effects (Miyazaki. 2005), but will also reverse the nandrolone decanoate induced perturbations in sperm characteristics, normalize the serum testosterone level, and restore the activities of the key steroidogenic enzymes in rodents that are treated with nandrolone and taurine (at a dosage equivalent to only 1.3g/day | Ahmed. 2014).

In spite of the fact that the administration of taurine did also prevent the nandrolone decanoate-induced testicular toxicity and DNA damage by virtue of its antioxidant, anti-inflammatory, and anti-apoptotic effects, I would like to point out that this article is not intended as an incentive for nandrolone doping.

While taurine is not made from the sperm of Belgian Blues it may still boost your testosterone levels - whether that's going to be by 140% as in this study is questionable, though.

From performance to health doping: If you are not into "natural performance enhances" and don't care about the direct performance increases, reduced oxidative damage and increases in glycogen repletion during workouts. I would recommend you reread the previous SuppVersity article about the testosterone boosting effects of taurine, it's ability to improve your strength and recovery during and after resistance training sessions, as well as it's ability to improve your glucose metabolism (Franconi. 2006; Carneiro. 2009), to increase your glucose sensitivity (Han. 2004; Nakaya. 2000), to prevent insulin resistance in hyperglycemic states (Haber. 2003), to prevent the development of hypertension as a result of fructose overfeeding (Rahman. 2011), to prevent the cardiac damage due to iron overload (Oudit. 2004), to protect you from the kidney damaging assault of chemotherapy (Saad. 2010), and god knows which benefits I have simply forgotten in the aforementioned list | Comment of Facebook!

References:

• Ahmed, Maha AE. "Amelioration of Nandrolone Decanoate-Induced Testicular and Sperm Toxicity in Rats by Taurine: Effects on Steroidogenesis, Redox and Inflammatory Cascades, and Intrinsic Apoptotic Pathway." Toxicology and Applied Pharmacology (2014).
• Alom, J., et al. "Cerebrospinal fluid taurine in Alzheimer's disease." Annals of neurology 30.5 (1991): 735-735.
• Arai, Heii, et al. "A preliminary study of free amino acids in the postmorten temporal cortex from Alzheimer-type dementia patients." Neurobiology of aging 5.4 (1985): 319-321. 
• Carneiro, Everardo M., et al. "Taurine supplementation modulates glucose homeostasis and islet function." The Journal of nutritional biochemistry 20.7 (2009): 503-511.
• Cuisinier, Claire, et al. "Role of taurine in osmoregulation during endurance exercise." European journal of applied physiology 87.6 (2002): 489-495.
• Dawson Jr, R., et al. "The cytoprotective role of taurine in exercise-induced muscle injury." Amino acids 22.4 (2002): 309-324. 
• Franconi, Flavia, et al. "Taurine supplementation and diabetes mellitus." Current Opinion in Clinical Nutrition & Metabolic Care 9.1 (2006): 32-36.
• Haber, C. Andrew, et al. "N-acetylcysteine and taurine prevent hyperglycemia-induced insulin resistance in vivo: possible role of oxidative stress." American Journal of Physiology-Endocrinology and Metabolism 285.4 (2003): E744-E753.
• Han, Jin, et al. "Taurine increases glucose sensitivity of UCP2-overexpressing β-cells by ameliorating mitochondrial metabolism." American Journal of Physiology-Endocrinology and Metabolism 287.5 (2004): E1008-E1018. 
• Kim, Hye Yun, et al. "Taurine in drinking water recovers learning and memory in the adult APP/PS1 mouse model of Alzheimer's disease." Scientific Reports 4 (2014).
• Menzie, Janet, et al. "Taurine and central nervous system disorders." Amino acids 46.1 (2014): 31-46.
• Miyazaki, T., et al. "Optimal and effective oral dose of taurine to prolong exercise performance in rat." Amino Acids 27.3-4 (2004): 291-298.
• Miyazaki, Teruo, et al. "Taurine inhibits oxidative damage and prevents fibrosis in carbon tetrachloride-induced hepatic fibrosis." Journal of hepatology 43.1 (2005): 117-125.
• Molina, José A., et al. "Decreased cerebrospinal fluid levels of neutral and basic amino acids in patients with Parkinson's disease." Journal of the neurological sciences 150.2 (1997): 123-127.
• Nakaya, Yutaka, et al. "Taurine improves insulin sensitivity in the Otsuka Long-Evans Tokushima Fatty rat, a model of spontaneous type 2 diabetes." The American journal of clinical nutrition 71.1 (2000): 54-58.
• Oudit, Gavin Y., et al. "Taurine supplementation reduces oxidative stress and improves cardiovascular function in an iron-overload murine model." Circulation 109.15 (2004): 1877-1885.
• Rahman, Mizanur M., et al. "Taurine prevents hypertension and increases exercise capacity in rats with fructose-induced hypertension." American journal of hypertension 24.5 (2011): 574-581.
• Saad, Sherif Y., and Ammar C. Al-Rikabi. "Protection effects of taurine supplementation against cisplatin-induced nephrotoxicity in rats." Chemotherapy 48.1 (2010): 42-48.
• Silva, Luciano A., et al. "Taurine supplementation decreases oxidative stress in skeletal muscle after eccentric exercise." Cell biochemistry and function 29.1 (2011): 43-49. 
• Takahashi, Yumiko, et al. "Post-exercise taurine administration enhances glycogen repletion in tibialis anterior muscle." The Journal of Physical Fitness and Sports Medicine 3.5 (2014): 531-537.
• Zhang, M., et al. "Role of taurine supplementation to prevent exercise-induced oxidative stress in healthy young men." Amino acids 26.2 (2004): 203-207.

Study Puts Taurine Back in the Limelight - Sprint Cycling in Trained Athletes Benefits from Taurine, not Caffeine!?

More evidence that the often high taurine content in your energy drinks is more than a mere marketing gag.

You will probably remember my recent article about the potentially underestimated contribution of taurine to the performance enhancing effects of Red Bull™ and co. (read it again). Now, a new study from the School of Sport, Health and Applied Science at the St Mary’s University in Great (soon small) Britain shows: Only taurine, yet not caffeine boosts the sprint cycling performance in trained athletes. And as if that wasn't enough, yet, the study also proves another benefit of taurine I've written about in the past: it reduces the typical (negative) side effects of high(er)-dose caffeine.

You can learn more about taurine & other amino acids at the SuppVersity

Taurine Pumps Up Strength & Recovery?

Taurine the Actual Active Agent in RedBull&Co

Taurine ➲ 180% Testosterone Increase

Taurine + BCAA Work Hand in Hand

Taurine Boosts Good Gut Bugs Sign.

3g Taurine Boost Glycogen Re-synthesis Sign.

For their study, the researchers from the UK who were supported by colleagues from Australia recruited seven male team sports players (age 20.8 ± 0.9 years; stature 1.76 ± 0.11 m; body mass 86.3 ± 10.2 kg). Despite the small sample size, the scientists' a priori calculation indicated that a sample size of seven was sufficient to identify differences between groups with a statistical power of 0.80.

The subjects were randomized, in a single-blind design to perform three Wingate tests, each separated by 2-min, an hour after ingesting

• caffeine (C) at a dosage of  5 mg/kg body mass,
• taurine (T) at a dosage of 50 mg/kg BM, 
• caffeine and taurine (C+T) at dosages of 5 mg/kg BM + 50 mg/kg, respectively, or 
• placebo capsules (P) with an identical look and weight

before being crossed over three follow-up experiment in which the subjects would consume one of the other treatments.

Figure 1: Taurine turns out to be the great fatigue modulator - if it's consumed w/out caffeine (Warnock 2017).

The subjects' performance was measured on an ergometer, whilst blood lactate, perceived exertion, heart rate (HR), mean arterial pressure (MAP) and rate pressure product (RPP) were measured at rest (pre-supplement), baseline (1-h post-supplement) and during and after exercise; and the results I plotted in Figure 1 speak for themselves.

A 2004 study by Miyazaki et al found dose-dependent increases in endurance w/ human eq. doses of ~0.25g, ~1,25g and ~6.25g of taurine.

You probably need more taurine, bro: The top dog in the energy drink market contains 2g taurine, which is more than you will find in many of the cheap copy cats, but less 50mg/kg for most of you. Accordingly, the study at hand the previously discussed meta-analysis of the ergogenic prowess of energy drinks and an older rodent study by Miyazaki et al (2004 | see Figure on the left) indicate that "more helps more" and thus suggest that many of the previously conducted studies, as well as your own efforts, could have failed to yield results because you didn't get to the ergogenic threshold which may be at 4-5g⁺.

In view of the relatively small study group, the scientists conducted a magnitude-based inference analysis to get to the bottom of the relevance of the effects they observed and found that...

• all of the supplements increased (small to moderate, likely to very likely) mean peak power (MPP), peak power (PP) and mean power (MP) compared to P, with greater MPP, PP and MP in T compared to C (small, possible)
• intra-sprint fatigue index (%FIIntra) was greater in the taurine (T) compared to placebo (P) and control (C) group - the practical relevance of this difference does yet appear to be smaller than that of the albeit likewise small decreased inter-sprint fatigue index (%FIInter) in the taurine (T) compared to the caffeine (C) group
• C and C+T increased HR, MAP and RPP compared to P and T at baseline (moderate to very large, likely to most likely); however, these only remained higher in C compared to all conditions in the final sprint.

What? Ok, let's simplify that a bit by taking a look at the plot of the fatigue and performance data in Figure 1 & 2 again. These graphs clearly reveal that (A) there was a sign. performance increase with all three supplements (Figure 2). Only the taurine (only) trial, however, (B) reduced the inter-sprint fatigue index (Figure 1) which appears to be the fatigue marker with greater relevance for most sports that require intermittent sprints.

Figure 2: The performance increases were virtually identical in all three supplement groups (Warncock 2017).

Accordingly, the practical implication is that using taurine, alone, may be the better choice for cyclists and other athletes whose sports involve short all-out sprints - the overall inter-group differences however are small and further research is warranted before one could make any definitive recommendations with respect to the combined or individual use of caffeine and taurine.

Taurine is probably at least as much a health as performance supplement

Figure 3: Possible mechanisms responsible for beneficial effect of taurine in prevention and amelioration of metabolic syndrome (Murakami 2013).

What I would like to repeat, though, is that taurine has not just been found to have (a) cytoprotective effects against exercise-induced muscle injury (Dawson 2002; da Silva 2013), (b) limit oxidative stress in skeletal muscle (Silva 2011).

Taurine (supplementation) has also been found to have sign. health benefits (Militante 2004) in obesity-induced hyperlipidemia (Zhang 2004), to keep homocysteine and thus heart disease risk in check (Ahn 2009), to reverse endothelial dysfunction in high risk groups, like young type I diabetics (Moloney 2010) or to be useful in the treatment of non-alcoholic fatty-liver disease (Gentile 2011).

Furthermore, many scientists believe that its supplementation or high dietary intakes could be usfeful in the prevention of diabetes and metabolic syndrome (Murakami 2013; Imae 2014).

A recent meta-analysis of all studies that investigate the performance enhancing effects of energy drinks supports the notion that taurine is much more important for their beneficial effects on your performance than caffeine | read more

So, taurine only it is? If that's the take home message you remember, you have a problem... at least if your sport does not require only short bursts of all out sprinting. Caffeine has previously been shown to excel in long(er) duration exercise (Denadai 1998; Ganio 2009); and while further research is clearly indicated these observations imply that a combination of both taurine and caffeine may be the best choice for all athletes whose sports involve long(er) and/or low(er) intensity intervals of physical activity, where the beneficial effects of taurine on the subjects' heart rate, mean arterial pressure and pressure product may come handy especially but not exclusively for people with cardiovascular problems | Comment on the SuppVersity Facebook Page!

References:

• Ahn, Chang Soon. "Effect of taurine supplementation on plasma homocysteine levels of the middle-aged Korean women." Taurine 7. Springer New York, 2009. 415-422.
• Dawson, Jr, R., et al. "The cytoprotective role of taurine in exercise-induced muscle injury." Amino acids 22.4 (2002): 309-324.
• Denadai, B. S., and M. L. D. R. Denadai. "Effects of caffeine on time to exhaustion in exercise performed below and above the anaerobic threshold." Brazilian journal of medical and biological research 31.4 (1998): 581-585.
• Ganio, Matthew S., et al. "Effect of caffeine on sport-specific endurance performance: a systematic review." The Journal of Strength & Conditioning Research 23.1 (2009): 315-324.
• Gentile, Christopher L., et al. "Experimental evidence for therapeutic potential of taurine in the treatment of nonalcoholic fatty liver disease." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 301.6 (2011): R1710-R1722.
• Imae, Masato, Toshiki Asano, and Shigeru Murakami. "Potential role of taurine in the prevention of diabetes and metabolic syndrome." Amino Acids 46.1 (2014): 81-88.
• Moloney, Michael A., et al. "Two weeks taurine supplementation reverses endothelial dysfunction in young male type 1 diabetics." Diabetes and Vascular Disease Research 7.4 (2010): 300-310.
• Militante, Julius D., and John B. Lombardini. "Dietary taurine supplementation: hypolipidemic and antiatherogenic effects." Nutrition Research 24.10 (2004): 787-801.
• Miyazaki, T., et al. "Optimal and effective oral dose of taurine to prolong exercise performance in rat." Amino acids 27.3 (2004): 291-298.
• Murakami, S., and Y. Yamori. "Taurine and Longevity–Preventive Effect of Taurine on Metabolic Syndrome." Bioactive Food as Dietary Interventions for the Aging Population (2013): 159.
• Silva, Luciano A., et al. "Taurine supplementation decreases oxidative stress in skeletal muscle after eccentric exercise." Cell biochemistry and function 29.1 (2011): 43-49.
• da Silva, Luciano A., et al. "Effects of taurine supplementation following eccentric exercise in young adults." Applied Physiology, Nutrition, and Metabolism 39.1 (2013): 101-104.
• Warnock, Rory, et al. "The Effects of Caffeine, Taurine or Caffeine-Taurine Co-Ingestion on Repeat-Sprint Cycling Performance and Physiological Responses." International Journal of Sports Physiology and Performance (2017): 1-24.
• Zhang, M., et al. "Beneficial effects of taurine on serum lipids in overweight or obese non-diabetic subjects." Amino acids 26.3 (2004): 267-271.

Up To 180% Increase in Testosterone w/ Taurine? Androgen Boost Just One of the "Side Effects" of Cysteine Derivative That Won't Benefit (Pre-)Diabetic Baby-Boomers, Only

Image 1: No, taurine is not made from the sperm of Belgian Blues and no it won't make you look like one overnight, either ;-)

After yesterday's allegedly pretty complicated post on the fallacious ups and downs in body weight from repetitive dieting and episodes of overeating, I decided it was about time to readdress one of your all-time favorites: supplemental testosterone boosting. Instead of the next best herb from the Brazilian jungle that has a "history as a potent aphrodisiac in traditional medice" or the shrub that can be found "only in a specific region of the remote [... insert whatever your marketing guy believes would increase sales here]", I decided to take another look at one of the established readily available and dirt cheap ways to give your natural androgen production, fertility, fatty acid and glucose metabolism a leg - taurine, or 2-aminoethanesulfonic acid (which is, by the way, not produced from bull semen, although its name, which has the greek word "tavros", or ταύρος for the wanna-be intellectuals out there, would suggest ;-)

Taurine doubles testosterone production in diabetic rats

The reason I am addressing this again is the recent publication of a study on the beneficial effects of supplemental taurine, administered at a dose of 500mg/kg (human equivalent: 80mg/kg, or 3-4g /day) on the following diabetes related ailments:

What's up with intraperitoneal administered drugs? When something is injected into the peritoneal cavity the cannot vomit whatever scientists would otherwise have to stuff down their pieholes or inject into their tiny veins back up. Unfortunately the bioavailability is usually higher than via the oral route with the differences varying profoundly between compounds. Melatonin, for example, has a bioavailability of 54% when administered orally and 74% for i.p. injections (based on 10mg/kg dose; cf. Yeleswaram. 1997).

• wasting (loss of body weight),
• testicular damage,
• defect spermatogenesis,
• systemic oxidative damage,
• DNA damage,
• loss of natural antioxidant defense,
• low testosterone

in six-week-old male wistar rats. As the data in figure 1 goes to show, the non-essential amino acid, both humans and rodents (not so cats) can produce from dietary cysteine, was administered (as it is common practice in rodent studies) not orally, but via the peritoneal cavity had profound effects specially with regard to the oxidative damage and restoration of the natural antioxidant defense system.

Figure 1: Relative Body, testicular and epididymal weight (left); relative testicular & serum MDA, testicular catalase, serum testosterone and DNA damage (middle) and testicular damage (tissue samples) and Johnson score for spermatogenesis (right); all data except Johnson scores expressed relative to control (calculated based on Tsounapi. 2012)

Yet despite the fact that the serum malondialdehyde (CH2(CHO)2, marker of oxidative damage) decreased from 185% in the streptozotocin treated and consequently diabetic animals to 92% in the animals who received 500mg/kg of taurine for 4 weeks after the streptozotocin injection (50mg/kg intraperitoneally) and were thus lower than in the healthy control animals, the 7.5x increas in blood glucose which was not ameliorated by taurine was obviously too much for the testosterone levels to return into the normal range.

The average American is likely to benefit, as well

Figure 2 (Shin. 2012): Adjusted mean values of total testosterone according to fasting plasma glucose (FPG) - Q1 (65 - 88 mg/dL), Q2 (88 - 94 mg/dL), Q3 (94 mg/dL - 100 mg/dL), and Q4 (100 - 126 mg/dL; prediabetic according to American Diabetes Association)

With a 2x increase over the diabetic group the testosterone boosting effect in the Tsounapi study was yet still highly significant and could, in view of the results of Shin et al. who found that even high-normal (fasting blood-glucose levels ≥ 88 mg/dL) were associated with a decrease in testosterone levels in prediabetic and non-diabetic men (Shin. 2012; ,cf. figure 2), help one or another of the men among the estimated >79,000,000 American adults aged 20 years who are prediabetic (CDC. 2010) to bump their -25% reduced testosterone levels back into the normal range.

Adequate dosages are probably higher for diabetics

That would obviously require adequate dosing schemes which would, according to the Tsounapi study range from ~3-5g and are thus more than twice as high as the 1.5g /day Brøns et al. administered to overweight men with a genetic predisposition for type II diabetes mellitus without seeing the expected outcomes in terms of increased insulin sensitivity and glucose tolerance (Brøns. 2004). Especially in diabetics, whose ability to absorb taurine is decreased (-32%), while the amount of taurine they excrete is increased (+35%; cf. Merheb. 2007), dosages in the 5g+ range (like 3x2g per day with meals) could be very well indicated - not least because the previously calculated human equivalent dose did not account for the increased bioavailability from intraperitoneally injected vs. orally ingested taurine.

Taurine, women, pregnancy and healthy children

Likewise, low(-ered) serum levels of taurine have been identified as a correlate of gestational diabetes by Seghieri et al. According the researchers from Italy,

[...] plasma taurine was inversely related to previous gestational area-under-curve of glucose and directly related to post-gestational CP/glucose [CP: C-reactive protein, important marker of inflammation and correlate of cardiovascular disease and other ailments], as well to CP/glucose measured during pregnancy (p<0.05 for both). [Moreover, the] relative risk of altered glucose metabolism during previous pregnancies [impaired glucose tolerance and gestational diabetes] was higher as plasma taurine decreased, even after adjusting for age, time-lag from pregnancy, body mass index and family history of diabetes (OR: 0.980; CI 95%: 0.963-0.999, p=0.003)

Thus taurine is by no means a "man's amino acid" - despite the fact that its concentration is particularly high in "manly" foods, such as fish and meat. In this context, the results of Kim et al. appear noteworthy, as well.

Taurine an essential component of breast milk

Taurine has a whole host of additional beneficial effects related to the prevention of comorbidities of diabetes (Ito. 2012):

• diabetic nephropathy
• diabetic retinopathy
• diabetic neuropathy
• diabetic cardiomyopathy

The Korean researchers found that the taurine content (obviously a vitally important nutrient for infants, as well) is profoundly decreased in the breast milk even of lacto-ovovegetarian mothers, compared to their non-vegetarian counterparts (31.0-54.4 mg/L vs. 19.1-52.3 mg/L; Kim. 1996). That this could be a substantial risk factor for

• diabetes, insulitis and pancreatic dysfunction (Arany. 2004)
• cardiovascular disease (Kulthinee. 2010)
• distortions of the renin-angiotensin system (Thaeomor. 2010)
• high blood pressure (Roysommuti. 2009)
• kidney problems (Roysommuti. 2010)

and all sorts of downstream complications, regardless of the obesity / glucose tolerance of the mother, is supported by a whole host of studies (see references above); and novel papers on related benefits appear on an almost monthly basis.

You don't have to be (pre-)diabetic, on the SAD diet or pregnant to benefit

Despite the fact that (pre-)diabetics, women in childbearing age and the notorious "average American" on his "standard American diet" (mostly this is identical to being prediabetic, as the previously cited data from the CDC goes to show; cf. CFC. 2010) already cover the majority of average Joes and Janes in the Westernized (or should I say super-sized?) world, this would not be the SuppVersity if today's post would not also have some merit for physical culturists.

Image 2: Those of you who listened to my dissertations in Episode III of the Amino Acids for Super Humans series on Super Human Radio, back in the day, will remember: Taurine ain't for obese pre-diabetics, only ;-)

Now, those of you who have been around for a while will probably remember the series of shows I did with my friend Carl Lanore, host, head, heart and soul of the Super Human Radio Network, on "Amino Acids for Super Humans" - and maybe, some of you have even read all the shownotes and will thus remember a study I mentioned both on the air, as well as in detailed notes on Episode III of the Amino Acids for Super Humans series.

T for T: Taurine for testosterone for athletes and beyond

The study I am talking about was conducted by Yang et al. in 2009 and compared the effects of taurine supplementation on male reproduction in rats of different ages. With ~1% taurine at a water the rodents received, which would be (assuming an average weight & water consumption) be equivalent to ~15g for an adult human being - or 3x5g per day (Note: I am emphasizing the split dosages for two reasons: (1) I think it is a mistake not to consider the intricacies of supplementation and chronic low dose vs. bolus does make a huge difference with other supplements, e.g. "Never(!) Sip Your Whey, If You Want to Kickstart Protein Synthesis", and (2) taurine is somewhat harsh on the stomach and taking 15g in one sitting is almost guaranteed to make you sprint to the toilette within no time ;-)

Figure 3: Serum testosterone levels (in mIU/ml) after 22 (baby) and 30 days (adult and aged rats) treatment with or without 1% taurine in drinking water (adapted from Yang. 2009)

As the data I have compiled in figure 3 goes to show, the chronic taurine administration lead to statistically significant increases in serum testosterone levels in rodents from all three age groups, i.e. baby rats (born to mothers who consumed the taurine enriched / control water during pregnancy), 10-week old adult rats, and 72-week old aged. Notwithstanding, the +46% increase in testosterone in the old rats, is probably still the most significant change as it would effectively restore the "old agers" testosterone levels to youthful heights, a change, the real-world significance of which cannot be underestimated in view of the effects "low" (as in "low" in lab standards, not as in low in bro-standards!) testosterone levels can have on your body composition as discussed in one of the installments of the "Intermittent Thoughts on Building Muscle" (specifically "Quantifying the Big T" > figure 2).

Image 3: Believe it or not, eggs contain sulfur and the raw materials to make taurine, but no taurine (cf. Zhao. 1998)

In conjunction with the improved antioxidant activity (SOD, ACP, GSH were all elevated), reduced oxidative damage and markers of muscle and liver damage, AST and ALT, as well as lipid oxidation, MDA, were all significantly reduced) and the increased expression of nitric oxide synthase and subsequent raise in nitric oxide production - by the way, the only parameter with statistical significance p<0.05 only in aged rats- it stands to reason that even people who have already found their way to physical culture are very likely to benefit from one or another gram of supplemental taurine. This is all the more true in view of the fact that even high taurine foods such as crustaceans and mollusks (300-800mg/kg), Albacore tuna (176mg/100g), lamb (110mg/100g), cod (108mg/100g), mackerel (78mg/100g), beef (77mg/100g), wild salmon (60mg/100g) and pork (40mg/100g) contain too little to get anywhere close to where the magic happens.

Implications: I guess based on the previous discussion it should be clear that of the numerous supplements that are marketed to gymrats and health-enthusiasts, alike, taurine unquestionably is one of the most promising ones (suggested dose non-diabetics start with 3x2g or 2x3g /day). Moreover, with the focus of today's post being on testosterone and glucose metabolism, I did not even mention all the proven and purported benefits of taurine, such as its ability to... keep exercise induced oxidative stress at bay (Zhang. 2004; Silva. 2011) prevent fructose induced hypertension (Rahman. 2011) facilitate cell hydration (Lang. 2012) increase skeletal muscle force production (EMS test, Goodman. 2009) preserve function and exercise capacity in skeletal and heart muscle (Ito. 2010) enhance the anorexic effects of insulin in the hyptohalamus (Solon .2012) maintain the lipolytic activity in fat cells (Piña-Zentella. 2012) increase fat oxidation while cycling (Rutherford. 2012; dosage 1.5g pre) counter the obesogenic effects of MSG (Nardelli. 2012 + more on MSG & obesity) increase stomach acid (Huang. 2011) ... and the list goes on and on and should theoretically be extended to all the benefits of TUDCA, I have written about only recently (cf. "Tauroursodeoxycholic Acid (TUDCA) - Research Overview"), because unless you don't have enough taurine all the cholesterol and bile in the world won't help your body to conjugate UDCA to taurine and make TUDCA from it ;-)

A word of caution: Since I know that you are just about to order a couple of bounds of taurine from your favorite bulk supplier, let me briefly mention a not-yet fully elucidated potential downside to excessive taurine supplementation (5g/day in divided doses does not seem to be a problem, though), which relates to its ability to act as a neurotransmitter in the brain: While Louzuda et al. point out that this can be an advantage and would render taurine a potential candidate for the treatment of Alzheimer's and other neurological disorders (Louzada. 2004), it's interactions with the GABA receptor in the brain and peripheral tissues (Hanretta. 1987; Albrecht. 2005; Jia. 2008) may be a problem for people with anxiety issues - whether it exerts anti- or pro-anxiety effects, is yet still a matter of constant debate and I am not even sure how reliable the rodent models are, by the means of which Chen et al., Kong et al. and Zhang et al. (Chen. 2004; Kong. 2006; Zhang. 2007) demonstrated anti-anxiety effects, El Idrissi et al. observed anti-anxiety effects after injection and pro-anxiety effect after chronic supplementation (El Idrissi. 2009), and Whirley et al. observed only "subtle" if not non-existant effects (Whirley. 2008).

References:

• Albrecht J, Schousboe A. Taurine interaction with neurotransmitter receptors in the CNS: an update. Neurochem Res. 2005 Dec;30(12):1615-21. Review. 
• Arany E, Strutt B, Romanus P, Remacle C, Reusens B, Hill DJ. Taurine supplement in early life altered islet morphology, decreased insulitis and delayed the onset of diabetes in non-obese diabetic mice. Diabetologia. 2004
• Brøns C, Spohr C, Storgaard H, Dyerberg J, Vaag A. Effect of taurine treatment on insulin secretion and action, and on serum lipid levels in overweight men with a genetic predisposition for type II diabetes mellitus. Eur J Clin Nutr. 2004 Sep;58(9):1239-47.
• CDC. Centers for Disease Control and Prevention. National diabetes fact  sheet: national estimates and general  information on diabetes and prediabetes  in the United States, 2011. Atlanta, GA: U.S. Department of Health and Human  Services, Centers for Disease Control and  Prevention, 2011. 
• Chen SW, Kong WX, Zhang YJ, Li YL, Mi XJ, Mu XS. Possible anxiolytic effects of taurine in the mouse elevated plus-maze. Life Sci. 2004 Aug 6;75(12):1503-11.   
• El Idrissi A, Boukarrou L, Heany W, Malliaros G, Sangdee C, Neuwirth L. Effects of taurine on anxiety-like and locomotor behavior of mice. Adv Exp Med Biol. 2009;643:207-15.
• Goodman CA, Horvath D, Stathis C, Mori T, Croft K, Murphy RM, Hayes A. Taurine supplementation increases skeletal muscle force production and protects muscle function during and after high-frequency in vitro stimulation. J Appl Physiol. 2009 Jul;107(1):144-54. Epub 2009 May 7.
• Hanretta AT, Lombardini JB. Is taurine a hypothalamic neurotransmitter?: A model of the differential uptake and compartmentalization of taurine by neuronal  and glial cell particles from the rat  hypothalamus. Brain Res. 1987 May;434(2):167-201. Review.
• Huang KH, Chang CC, Ho JD, Lu RH, Tsai LH. Role of taurine on acid secretion in the rat stomach. J Biomed Sci. 2011 Feb 5;18:11. 
• Ito T, Oishi S, Takai M, Kimura Y, Uozumi Y, Fujio Y, Schaffer SW, Azuma J. Cardiac and skeletal muscle abnormality in taurine transporter-knockout mice. J Biomed Sci. 2010 Aug 24;17 Suppl 1:S20. Review.
• Ito T, Schaffer SW, Azuma J. The potential usefulness of taurine on diabetes mellitus and its complications. Amino Acids. 2012 May;42(5):1529-39. 
• Kim ES, Cho KH, Park MA, Lee KH, Moon J, Lee YN, Ro HK. Taurine intake of Korean breast-fed infants during lactation. Adv Exp Med Biol. 1996;403:571-7. 
• Kong WX, Chen SW, Li YL, Zhang YJ, Wang R, Min L, Mi X. Effects of taurine on rat behaviors in three anxiety models. Pharmacol Biochem Behav. 2006 Feb;83(2):271-6.
• Kulthinee S, Wyss JM, Jirakulsomchok D, Roysommuti S. High sugar intake exacerbates cardiac reperfusion injury in perinatal taurine depleted adult rats. J Biomed Sci. 2010 Aug 24;17 Suppl 1:S22. 
• Lang F. Effect of cell hydration on metabolism. Nestle Nutr Inst Workshop Ser. 2011;69:115-26; discussion 126-30. Epub 2012 Jan 18.
• Louzada PR, Paula Lima AC, Mendonca-Silva DL, Noël F, De Mello FG, Ferreira ST. Taurine prevents the neurotoxicity of beta-amyloid and glutamate receptor agonists: activation of GABA receptors and possible implications for Alzheimer's disease and other neurological disorders. FASEB J. 2004 Mar;18(3):511-8.
• Merheb M, Daher RT, Nasrallah M, Sabra R, Ziyadeh FN, Barada K. Taurine intestinal absorption and renal excretion test in diabetic patients: a pilot study. Diabetes Care. 2007 Oct;30(10):2652-4. 
• Nardelli TR, Ribeiro RA, Balbo SL, Vanzela EC, Carneiro EM, Boschero AC, Bonfleur ML. Taurine prevents fat deposition and ameliorates plasma lipid profile in monosodium glutamate-obese rats. Amino Acids. 2011 Oct;41(4):901-8.
• Piña-Zentella G, de la Rosa-Cuevas G, Vázquez-Meza H, Piña E, de Piña MZ. Taurine in adipocytes prevents insulin-mediated H2O2 generation and activates Pka and lipolysis. Amino Acids. 2012 May;42(5):1927-35.
• Rahman MM, Park HM, Kim SJ, Go HK, Kim GB, Hong CU, Lee YU, Kim SZ, Kim JS, Kang HS. Taurine prevents hypertension and increases exercise capacity in rats with fructose-induced hypertension. Am J Hypertens. 2011 May;24(5):574-81.
• Roysommuti S, Suwanich A, Jirakulsomchok D, Wyss JM. Perinatal taurine depletion increases susceptibility to adult sugar-induced hypertension in rats. Adv Exp Med Biol. 2009;643:123-33.
• Roysommuti S, Malila P, Jirakulsomchok D, Wyss JM. Adult renal function is modified by perinatal taurine status in conscious male rats. J Biomed Sci. 2010 Aug 24;17 Suppl 1:S31.
• Rutherford JA, Spriet LL, Stellingwerff T. The effect of acute taurine ingestion on endurance performance and metabolism in well-trained cyclists. Int J Sport Nutr Exerc Metab. 2010 Aug;20(4):322-9.
• Seghieri G, Tesi F, Bianchi L, Loizzo A, Saccomanni G, Ghirlanda G, Anichini R, Franconi F. Taurine in women with a history of gestational diabetes. Diabetes Res Clin Pract. 2007 
• Shin JY, Park EK, Park BJ, Shim JY, Lee HR. High-normal Glucose Levels in Non-diabetic and Pre-diabetic Men Are Associated with Decreased Testosterone Levels. Korean J Fam Med. 2012 May;33(3):152-6. 
• Silva LA, Silveira PC, Ronsani MM, Souza PS, Scheffer D, Vieira LC, Benetti M, De Souza CT, Pinho RA. Taurine supplementation decreases oxidative stress in skeletal muscle after eccentric exercise. Cell Biochem Funct. 2011 Jan-Feb;29(1):43-9.
• Solon CS, Franci D, Ignacio-Souza LM, Romanatto T, Roman EA, Arruda AP, Morari J, Torsoni AS, Carneiro EM, Velloso LA. Taurine enhances the anorexigenic effects of insulin in the hypothalamus of rats. Amino Acids. 2012 Jun;42(6):2403-10.
• Thaeomor A, Wyss JM, Jirakulsomchok D, Roysommuti S. High sugar intake via the renin-angiotensin system blunts the baroreceptor reflex in adult rats that were perinatally depleted of taurine. J Biomed Sci. 2010 Aug 24;17 Suppl 1:S30.
• Tsounapi P, Saito M, Dimitriadis F, Koukos S, Shimizu S, Satoh K, Takenaka A,  Sofikitis N. Antioxidant treatment with edaravone or taurine ameliorates diabetes-induced testicular dysfunction in the rat. Mol Cell Biochem. 2012 Jul 5.
• Whirley BK, Einat H. Taurine trials in animal models offer no support for anxiolytic, antidepressant or stimulant effects. Isr J Psychiatry Relat Sci. 2008;45(1):11-8.
• Yang J, Wu G, Feng Y, Lv Q, Lin S, Hu J. Effects of taurine on male reproduction in rats of different ages. J Biomed Sci. 2010 Aug 24;17 Suppl 1:S9.  
• Yeleswaram K, McLaughlin LG, Knipe JO, Schabdach D. Pharmacokinetics and oral bioavailability of exogenous melatonin in preclinical animal models and clinical implications. J Pineal Res. 1997 Jan;22(1):45-51.
• Zhang M, Izumi I, Kagamimori S, Sokejima S, Yamagami T, Liu Z, Qi B. Role of taurine supplementation to prevent exercise-induced oxidative stress in healthy young men. Amino Acids. 2004 Mar;26(2):203-7.
• Zhang CG, Kim SJ. Taurine induces anti-anxiety by activating strychnine-sensitive glycine receptor in vivo. Ann Nutr Metab. 2007;51(4):379-86. 
• Zhao X, Jia J, Lin Y. Taurine content in Chinese food and daily intake of Chinese men. Adv Exp Med Biol. 1998;442:501-5.

Meta-Analysis: Could Energy Drinks be All About Taurine? Taurine, not Caffeine Predicts Performance Enhancement

While almost all energy drinks appear to have it, the evidence that taurine adds to the effects of caffeine has hitherto been unconvincing. Does this change with the latest study by a group of researchers from Brazil and Spain?

Energy drinks (ED) are all about caffeine, right? I have to admit. If you had asked me before I've read the latest study from the Londrina State University in Brazil and the Camilo José Cela University in Spain, I would have answered this question in the affirmative. I mean, come on... the strange add-ons the producers mix into their drinks have but one purpose: distinguish drink X from drink Y and, even more importantly, the healthier competition of plain coffee.

The fact that Souza, et al. observed in their latest meta-analysis that "a signifcant association between taurine dosage (mg) and performance (slope = 0.0001; p = 0.04), but not between caffeine dosage (mg) and performance (slope = 0.0009; p = 0.21)," caught my attention.

You can learn more about taurine & other amino acids at the SuppVersity

Taurine Pumps Up Strength & Recovery?

Taurine Improves Insulin + Glucose Metabolism

Taurine ➲ 180% Testosterone Increase

Taurine + BCAA Work Hand in Hand

43% Reduced Performance W/ BCAAs

3g Taurine Boost Glycogen Re-synthesis Sign.

Before we discuss how relevant this result of the authors' meta-regression actually is, it would be prudent to take a brief look at the methodology section of the paper: As you would expect, the scientists performed a systematic review and meta-analysis of published prior to January 2016 disregarding: (1) case reports; (2) review articles; (3) the use of drugs/substances which influ enced the outcome; (4) caffeine use without ED; (5) ED use without caffeine; (6) subjects on energy-restricted diets and/or weight reduction programs; (7) articles with animal models; (8) studies with samples that were ill or had physical limitations for exertion; (9) longitudinal studies.

Eventually N=34 articles that were (1) original; done with healthy adults; (2) reported the caffeine dose in the ED; (3) measured of physical performance pre- and post-intervention; (4) had a placebo group/session; (7) and offered enough data for effect size calculation were included in the scientists' statistical analysis.

Figure 1: Effects on endurance (left) and jumping (right) performance according to meta-analysis (Souza. 2016).

As you can see in Figure 1, the ED ingestion improved both, the subjects' performance in standardized endurance (ES = 0.53; p < 0.001 | Figure 1, left) and jump tests (ES = 0.29; p = 0.01 | Figure 1, right). Likewise beneficial were

• the effects on muscle strength and endurance (ES = 0.49; p < 0.001), and 
• sport-specifc actions (ES = 0.51; p < 0.001; cf. Table 1).

What did not improve, however, are the subjects' sprinting times - well, at least not significantly across the N=17 studies (ES = 0.14; p = 0.06).

Note: This article does not say that caffeine doesn't work! That caffeine works is beyond doubt. What the article does claim, however, is that the results of the meta-analysis, when combined with previous research, suggest that the ratio of caffeine to taurine could explain differences between the efficacy of various drinks (see bottom line for further discussion).

With a borderline significant effect and an increase of 16% in a study by Alford, et al., I would not discount the possibility that EDs would help Usain Bolt, as well.

Table 1: Subgroup analyses of categorical variables (Souza. 2016).

But didn't we want to talk about something else... oh, yes: the role of taurine! I guess some of you are already rolling their eyes. After all, I make no bones about my personal assessment that taurine may indeed be one of the most underrated amino acid supplements on the market (learn more).

Figure 2: Illustration of the subject- and supplement dependent continuous variables and their impact on the effect size indicated by the slope and significance of the results of the meta-regression (Souza. 2016).

So what's the evidence, then? Well with p-value of 0.04, taurine is the only subject / supplement related continuous variable that predicted the performance increase that was observed in the studies. The slope and thus the increase in effect size per unit of taurine in the corresponding meta-regression was however hardly relevant. No wonder, after all, previous studies, as well as the suspected stress-protective as well as anti-protein catabolis mechanisms (Zhang. 2004; HaeMi. 2003) suggest that taurine will have chronic rather than acute effects (cf. Rutherford. 2010); with the studies in this review being acute supplementation studies, these benefits couldn't be recorded, anyways.

Coffee - The Good, The Bad & The Interesting: 2-4 Cups of Coffee for Adiponectin. Roasted Filtered Coffee & High LDL!? The Optimal Caffeine / Taurine Ratios & the Buzz | more!

So, this begs the question: Even if the advantage is small, why could more taurine yield a higher exercise performance? Unfortunately, the authors didn't address this question in detail, but hey, I guess otherwise I would be useless... Now, I cannot tell you for sure what it is and without having access to the full dataset I cannot even confirm my hypothesis, but I still feel reminded of an older article I wrote about the synergy of caffeine and taurine, in which I presented evidence that a 1:10 mix of caffeine to taurine may be the optimal compromise between the jittery energy spike from caffeine and the calming (GABA mediated | Ripps. 2012) effects of taurine.

If we take a look at the continuum of caffeine and taurine intakes in the studies in the meta-analysis at hand, it turns out that - with caffeine dosages ranging from 40 and 325 mg and amount of taurine ranging from 71 to 3105 mg - many of the studies ended up being in that range.

If someone would now correlate the effect sizes and the caffeine:taurine ratio and find that there is a significant relationship between the two, this would provide more evidence that the implications I've formulated based on animal studies in 2013 (read the original article) could inform your supplement and dosing choices, so that 200-400 mg caffeine and 2,000-4,000 mg of taurine make a highly effective stack. As previously pointed out (see red box), this does not imply that caffeine alone wouldn't work, but having it with taurine in the correct ratio may be what makes one energy drink more effective than the other | Comment on Facebook!

References:

• Alford, Chris, Harriet Cox, and Robert Wescott. "The effects of red bull energy drink on human performance and mood." Amino acids 21.2 (2001): 139-150.
• HaeMi, Lee, Paik IlYoung, and Park TaeSun. "Effects of dietary supplementation of taurine, carnitine or glutamine on endurance exercise performance and fatigue parameters in athletes." Korean Journal of Nutrition 36.7 (2003): 711-719.
• Ripps, Harris, and Wen Shen. "Review: taurine: a “very essential” amino acid." (2012).
• Rutherford, Jane A., Lawrence L. Spriet, and Trent Stellingwerff. "The effect of acute taurine ingestion on endurance performance and metabolism in well-trained cyclists." International journal of sport nutrition 20.4 (2010): 322.
• Souza, Diego B., et al. "Acute effects of caffeine-containing energy drinks on physical performance: a systematic review and meta-analysis." European journal of nutrition (2016): 1-15.
• Zhang, M., et al. "Role of taurine supplementation to prevent exercise-induced oxidative stress in healthy young men." Amino acids 26.2 (2004): 203-207.