Brewers Yeast – Human grade Brewers Yeast is natural Vitamin B complex. It contains B1, necessary for the health of the nervous and digestive systems. B2, for the eyes, lips and mouth. B3, for balance of the adrenal gland. B5, resisting disease. B6, nervous system, appetite, digestion, liver, red blood cells and resisting infection. B12, lethargy and anaemia.