Natures Aid 300mg Brewers Yeast 500 Tablets are made from Saccharomyces cerevisiae and has long been used in the production of beer and wine. Brewer?s Yeast is also a nutritional supplement, providing a source of B vitamins, amino acids and minerals. Natures Aid Brewer?s Yeast tablets are manufactured using non-debittered Brewer?s Yeast powder, preserving the natural levels of B-vitamins.