Zinc is important for absorption and action of B-complex vitamins. It is required for protein synthesis, collagen formation, healthy immune system, and the ability of the body to heal from wounds. Zinc is absorbed in the small intestine and is stored in the liver, eyes, kidneys, pancreas, bones, muscles, prostate gland, sperm, nails, skin, hair, and white blood cells. Zinc inhibits 5-alpha reductase from converting testosterone into dihydrotestosterone (DHT) a form of testosterone that promotes prostate growth. Zinc increases testosterone, and sperm count. If a zinc deficiency exists sex drive is reduced in order to conserve the zinc (zinc is concentrated in semen). Zinc is involved in protein synthesis, muscle contraction, formation of insulin, maintaining acid-base balance, synthesis of DNA, brain functions. Excessive sweating leads to loss of up to 3 mg per day.