Q: What is brewer's yeast, and are supplements worth taking?
A: Like baker’s yeast, brewer’s yeast is a strain of Saccharomyces cerevisiae. As its name suggests, brewer’s yeast is used in beer production. It’s sold in deactivated form as a nutritional supplement (flakes or powder), supplying protein, B vitamins, and trace minerals such as chromium and manganese. “Nutritional yeast” is usually also a strain of Saccharomyces cerevisiae. Like brewer’s yeast, nutritional yeast supplements are inactive. None of these yeasts are related to Candida albicans, the yeast that most commonly causes vaginal yeast infections.
Yeast supplements vary nutritionally, depending on the medium on which the yeast is grown, how they are processed, and whether they are fortified. Some are much higher in chromium or selenium, for example, and many, but not all, are rich in folic acid. Most contain little vitamin B12.
There’s no evidence that yeast supplements will boost energy, improve athletic performance, or have other health benefits, as is sometimes claimed. Chromium-rich yeast is often touted for controlling blood cholesterol and diabetes, but the evidence that chromium has such effects is inconsistent.
Use yeast supplements if you like the way they taste. Nutritional yeast has a nutty, cheesy flavor; brewer’s yeast tends to be more bitter, though de-bittered products are available. Compare labels for nutrients, especially if you are vegan and are looking for extra B12. It’s always best to get nutrients from a healthy diet. But if you do need supplemental nutrients—for instance, if you are a woman of childbearing age and are trying to get extra folic acid, as recommended—a more reliable way to get them is with a basic multivitamin and mineral pill.
Also see Cholesterol-Lowering Supplements.