Vitamin A is vital for healthy skin and is a famous antioxidant. It plays a role in absorbing and regulating calcium and phosphorus. It helps build strong bones, teeth, and skin. It is vital to the health of the nervous system and kidneys. It can be derived from the sun's action on the skin but the more tanned the skin, the less is absorbed.
Studies suggest that mixed carotenes provide a protective effect superior to beta-carotene alone.
Andrew Weil, M.D., suggests 25,000 IU of mixed natural carotenes in addition to adding yellow and orange fruits and vegetables, tomatoes, and dark, leafy greens to your diet. He also reminds men to be sure to include lycopene as it helps prevent prostate cancer. The B vitamins provide energy, may relieve fatigue, support the adrenal glands, and help metabolize hormones. A single B vitamin should be used only if you feel you have an increased need for that particular B vitamin. It promotes the conversion of tryptophan to niacin or serotonin.