Taurine's Research History, From Bile Acids to Energy Drinks
Taurine is one of the few amino acids your body does not build into protein, and it still shows up in three very different stories: bile salts, preterm infant formula, and the energy drink can. This page follows the research record for each one and stops where the sources stop.
The history of taurine is three separate research stories that happen to share one molecule. The first concerns bile salts, the second concerns preterm infants fed formula, and the third concerns the energy drink can. The record for each story stops at a different point, so this page follows each one only as far as the sources allow. The most surprising fact comes from a regulatory file. In its 2015 response to a GRAS notice for taurine in beverages, the U.S. Food and Drug Administration summarized the notifier's manufacturing method: taurine synthesized from sodium bisulfite, ethylene oxide, ammonia, and sulfuric acid, then purified, filtered, and crystallized. The route described is chemical synthesis, not extraction from bile. ## What taurine does, and why it is not a protein building block Taurine is one of the few amino acids the body does not build into proteins. According to PubMed, a 2012 review in *Molecular vision* by Harris Ripps and Wen Shen lists its roles: regulating cell volume, modulating intracellular calcium, and providing a substrate for bile salt formation. The same review calls taurine one of the most abundant amino acids in the brain, retina, and muscle tissue. The bile link is the piece of taurine biology the review states most directly. ([Ripps and Shen, 2012](https://pubmed.ncbi.nlm.nih.gov/23170060/)) ## How infant formula research put taurine on the nutrition list The formula story starts with a question about amino acids in newborns. In 1970, J. A. Sturman, G. Gaull, and N. C. Raiha reported in *Science* that cystathionase activity could not be measured in the livers of 24 human fetuses and 3 premature infants. They suggested cystine might be an essential amino acid for the immature human. The abstract does not mention taurine, so treat the paper as background for the formula work, not as a taurine result. ([Sturman et al., 1970](https://doi.org/10.1126/science.169.3940.74)) Taurine entered the research when formula researchers measured what preterm infants were getting. In 1983, Rassin, Gaull, and colleagues reported in *Pediatrics* that preterm infants fed an unsupplemented formula had lower plasma and urine taurine than infants fed human milk. Adding taurine to the formula restored those levels to the human-milk range. Taurine was the only amino acid that ran lower in the formula group than in the human-milk group. ([Rassin et al., 1983](https://pubmed.ncbi.nlm.nih.gov/6823419/)) The clearest randomized comparison in this run is a 1987 trial in *Pediatric Research*. Fifteen low birth weight infants were randomized to one of two premature formulas, one with added taurine. Nine more infants fed their mothers' preterm milk served as a comparison group. The taurine group's coefficient of fat absorption averaged 92.5 percent, against 87.5 percent in the unsupplemented group, and growth was the same across all three groups. ([Galeano et al., 1987](https://doi.org/10.1203/00006450-198707000-00016)) A 1993 trial in the *American Journal of Clinical Nutrition* pushed the question further. Thirty newborns were split into five groups of six by gestational age and weight, then randomly assigned to normal or taurine-supplemented formula. Only the preterm infants, those under 33 weeks, showed the taurine-linked changes in cholesterol synthesis, bile acid excretion, and fat absorption. The authors recommended taurine for preterm infants not on human milk, based on that subgroup. ([Wasserhess et al., 1993](https://doi.org/10.1093/ajcn/58.3.349)) The formula studies answer a narrow question about premature infants. They measured blood and urine taurine, fat absorption, and growth. They say nothing about adult supplement use. ## What the energy drink regulators said, and what they left open The energy drink record is mostly regulatory. In February 2009, the European Food Safety Authority (EFSA) reported that exposure to taurine through regular energy drink consumption was not a safety concern. Its panel based that view on mean and high regular intakes of 125 ml and 350 ml of energy drink per day. It cited a no observed adverse effect level of 1,000 mg per kilogram of body weight per day for both taurine and d-glucuronolactone. ([EFSA, 2009](https://www.efsa.europa.eu/en/news/efsa-adopts-opinion-two-ingredients-commonly-used-some-energy-drinks)) Two details on EFSA's page matter more than the headline. The exposure figures rested on consumption data reported in 2003, and the panel said newer exposure data, especially for adolescents and young adults, may need to be collected. The panel also considered that acute problems reported in young people, some of them fatal, could be due to the known side effects of high caffeine intake. It found no scientific evidence for a causal link to taurine. The page is marked as more than ten years old, so read it as a 2009 verdict. The U.S. record is a 2015 letter. The notice, dated May 2015, came from Intertek Scientific and Regulatory Consultancy and concluded that taurine is GRAS for noncarbonated, flavored, water-based beverages at 0.0045 percent. FDA answered in December 2015 that it had no questions about that conclusion, and it said it had not made its own GRAS determination. The notifier estimated mean dietary exposure from the notified use at 15.9 mg per person per day, rising to 24.8 mg once supplement use was counted. FDA also said that label claims for taurine products belong to a different office, and that its review did not evaluate whether any such claim would be supported. ([FDA, GRN 000586](https://www.fda.gov/food/gras-notice-inventory/agency-response-letter-gras-notice-no-grn-000586)) The same notice estimated that omnivorous diets provide 9 to 400 mg of taurine a day, and it noted that taurine occurs naturally in meat and dairy. Food, in other words, is a source of taurine too. ## What the sources do not settle This page does not name who first isolated taurine. A search turned up an 1827 paper on ox bile, but the publisher page returned no text and the digital copy was blocked to us, so we did not use it. For the same reason, the naming story is left out. We found no primary or institutional source that says the name comes from the Latin word for bull. Nothing in these sources connects ox bile to energy drinks. The taurine in FDA's file is made by chemical synthesis, and the bile material in the review concerns body chemistry, not the can. The EFSA opinion uses 2003 exposure data, and the FDA letter reports the notifier's estimates, not FDA's own. Neither is a current survey of how much taurine people take in from energy drinks. ## Bottom line Three narrow points hold. EFSA reported no safety concern for the regular energy drink intakes it modeled, and FDA raised no questions about a 2015 GRAS notice for beverages. The 1987 and 1993 infant trials are small, and the 1993 taurine effects appeared only in the preterm subgroup. None of the human studies cited here measured a benefit in adults. What drove the 2015 notice for beverages? None of the sources in this run say. ## Next reads - [The mitochondrial health guide](/health/mitochondrial-health-complete-guide) for the wider cellular background to the cell volume and calcium roles described above. - [The NAD longevity guide](/health/nad-longevity-complete-guide) for the other cellular biology pillar this page connects to. - [The history of creatine](/blog/history/history-of-creatine-from-meat-extract-to-sports-shelf), a parallel story about a compound that moved from meat extract to the sports shelf. ### Related reading - [the carnitine origin story from meat extract to cellular fuel](/blog/history/history-of-carnitine-from-meat-extract-to-cellular-fuel) - [the essential amino acids origin story from casein to William Rose](/blog/history/history-of-essential-amino-acids-from-casein-to-william-rose)