Brewer's yeast is made from a one-celled fungus called Saccharomyces cerevisiae and is used to make beer. It has been grown and used as a nutritional supplement for years. Brewer's yeast is a rich source of minerals -- particularly selenium; protein; B-complex vitamins, and chromium, an essential trace mineral that helps the body maintain normal blood sugar levels.
Brewer's yeast tastes bitter and should not be confused with baker's yeast, nutritional yeast, or torula yeast. All those types of yeast are low in chromium.
The B-complex vitamins in brewer's yeast include B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B9 (folic acid), and H or B7 (biotin). These vitamins help break down carbohydrates, fats, and proteins, which provide the body with energy. They also support the nervous system, help maintain the muscles used for digestion, and keep skin, hair, eyes, mouth, and liver healthy.
Brewer's yeast does not contain vitamin B12, an essential vitamin found in meat and dairy products.