Taurine occurs naturally in fish and meat. The average daily intake for the omnivorous diet was determined to be about 58 mg (range from 9 to 372 mg), while it was lower or negligible for the strict vegan diet. In another study, taurine intake was estimated to be generally less than 200 mg/day, even among people eating a high-meat diet. According to a third study, estimates of taurine intake varied between 40 and 400 mg/day.

The availability of taurine depends on how the food was prepared, the effects of raw food retaining the most taurine, and roasting or boiling causing the greatest loss of taurine.

The vegans were found to have significantly lower levels of taurine than a control group on a standard American diet. Plasma taurine was 78% of control values and urinary taurine was 29%.

Premature infants are thought to be deficient in the enzyme needed to convert cystathionine to cysteine and therefore may be deficient in taurine. Taurine is found in breast milk and has been added to many infant formulas since the early 1980s as a precautionary measure. However, this practice has never been rigorously studied and thus has not been shown to be necessary or even beneficial.

Energy Drinks and Workout Supplements

Taurine is an ingredient in some energy drinks. Many contain 1000 mg per serving,[24] some as much as 2000 mg.

It is also found in various dietary supplements for athletes.