Brewer’s yeast: How to use it for health and beauty Brewer’s yeast is a product produced when barley, specifically gluten, decomposes. It is a fermented substance. Brewer’s yeast is a fungus that is used for fermentation, especially in the production of beer, wine, and bread. It contains significant amounts of vitamins (in particular, B complex) and proteins, which is why it can do amazing things for your hair and overall health. Usually people consume brewer’s yeast…"Brewer’s yeast: How to use it for health and beauty"