Scurvy juice, which is high in vitamin C. Though redundant in the presence of a balanced diet, various nutritional supplements are available that provide ascorbic acid well in excess of that required to prevent scurvy. Some animal products, including liver, muktuk (whale skin), oysters, and parts of the central nervous system, including the adrenal medulla, brain, and spinal cord, contain large amounts of vitamin C, and can even be used to treat scurvy. Fresh meat from animals which make their own vitamin C (which most animals do) contains enough vitamin C to prevent scurvy, and even partly treat it. In some
Vitamin A an adequate intake of provitamin A carotenoids from fruits and vegetables or preformed vitamin A from animal and dairy products. Early weaning from breastmilk can also increase the risk of vitamin A deficiency. Secondary vitamin A deficiency is associated with chronic malabsorption of lipids, impaired bile production and release, and chronic exposure to oxidants, such as cigarette smoke, and chronic alcoholism. Vitamin A is a fat-soluble vitamin and depends on micellar solubilization for dispersion into the small intestine, which results in poor use of vitamin A from low-fat diets. Zinc deficiency can also impair absorption, transport, and metabolism of vitamin