Thiamine (Vitamin B1) helps to increase energy, mental focus, prevent memory loss, and decrease nerve damage. Vitamin B1 is necessary for RNA and DNA synthesis, and is important for the myelin sheath of the nervous system, relating to nerve transmission. A high carbohydrate and sugar rich diet will deplete B vitamins, including B1. Diabetes and stress also deplete B vitamins, including B1. 100 capsules.