Vitamin D3
D-3 is necessary for the utilization of calcium and phosphorus, and for the assimilation of Vitamin A. It also has a strong immune enhancing effect. In the tropics, where sunshine makes Vitamin D deficiency rare, osteoporosis, cataracts, colon and prostate cancer are far less common. Vitamin D works synergistically with Vitamin A to control cancer by inducing certain types of cancer cells to differentiate into normal cells to stop multiplying uncontrollably. The effect is so pronounced that drug companies are working on patentable analogs for drug therapy.