NIH - Vitamins (Medical Encyclopedia) “Vitamins are grouped into two categories: • Fat-soluble vitamins are stored in the body's fatty tissue. • Water-soluble vitamins must be used by the body right away. Any left over water-soluble vitamins leave the body through the urine. Vitamin B12 is the only water-soluble vitamin that can be stored in the liver for many years. Function Return to top Each vitamin has specific functions. You can develop health problems (deficiency disease) if you do not get enough of a particular vitamin. Vitamin A helps in the formation and maintenance of healthy teeth, bones, soft tissue, mucous membranes, and skin. Vitamin B6 is also known as pyridoxine. The more protein a person eats, the more vitamin B6 is needed to help the body use the protein. Vitamin B6 helps form red blood cells and maintain brain function, among other things. Vitamin B12, like the other B vitamins, is important for metabolism. It also helps form red blood cells and maintain the central nervous system. Vitamin C, also called ascorbic acid, is an antioxidant that promotes healthy teeth and gums. It helps the body absorb iron and maintain healthy tissue. It also promotes wound healing. Vitamin D is also known as the "sunshine vitamin," since it is made by the body after being in the sun. Ten to 15 minutes of sunshine three times per week is enough to produce the body's requirement of vitamin D. This vitamin promotes the body's absorption of calcium, which is essential for the normal development and maintenance of healthy teeth and bones. It also helps maintain proper blood levels of calcium and phosphorus. Vitamin E is an antioxidant also known as tocopherol. It plays a role in the formation of red blood cells and helps the body use vitamin K. Vitamin K is not listed among the essential vitamins, but without it blood would not stick together (coagulate). Some studies suggest that it helps promote strong bones in the elderly. Biotin is essential for the metabolism of proteins and carbohydrates, and in the production of hormones and cholesterol. Niacin is a B vitamin that helps maintain healthy skin and nerves. It is also has cholesterol-lowering effects. Folate works with vitamin B12 to help form red blood cells. It is necessary for the production of DNA, which controls tissue growth and cell function. Any woman who is pregnant should be sure to get enough folate. Low levels of folate are linked to birth defects such as spina bifida. Many foods are now fortified with folic acid. Pantothenic acid is essential for the metabolism of food. It is also plays a role in the production of hormones and cholesterol. Riboflavin (B2) works with the other B vitamins. It is important for body growth and the production of red blood cells. Thiamine (B1) helps the body cells change carbohydrates into energy. It is also essential for heart function and healthy nerve cells. Food Sources Return to top FAT-SOLUBLE VITAMINS Vitamin A: • Eggs • Meat • Milk • Cheese • Cream • Liver • Kidney • Cod • Halibut fish oil Vitamin D: • Cheese • Butter • Margarine • Cream • Fortified milk • Fish • Oysters • Cereals Vitamin E: • Wheat germ • Corn • Nuts • Seeds • Olives • Spinach and other green leafy vegetables • Asparagus • Vegetable oils and products made from vegetable oils, such as margarine Vitamin K: • Cabbage • Cauliflower • Spinach • Soybeans • Cereals WATER-SOLUBLE VITAMINS Folate: • Green, leafy vegetables • Fortified foods Niacin (B3): • Dairy products • Poultry • Fish • Lean meats • Nuts • Eggs • Legumes • Enriched breads and cereals Pantothenic acid and biotin • Eggs • Fish • Dairy products • Whole-grain cereals • Legumes • Yeast • Broccoli and other vegetables in the cabbage family • White and sweet potatoes • Lean beef Thiamine (B1): • Fortified breads, cereals, and pasta • Whole grains • Lean meats • Fish • Dried beans • Peas • Soybeans • Dairy products • Fruits and vegetables Vitamin B12: • Meat • Eggs • Poultry • Shellfish • Milk and milk products Vitamin C (ascorbic acid) • Citrus fruits and juices • Strawberries • Tomatoes • Broccoli • Turnip and other greens • Sweet and white potatoes • Cantaloupe Most other fruits and vegetables contain some vitamin C; fish and milk contain small amounts. “

Supplement Your Knowledge of Vitamin D (2008) “How much vitamin D do I need? The current recommended daily dose of vitamin D is 200 IU for people up to age 50, 400 IU for people aged 51 to 70, and 600 IU for people over age 70. That's not enough, Boston University vitamin D expert Michael Holick, MD, PhD, tells WebMD. Holick recommends a dose of 1,000 IU a day of vitamin D for both infants and adults -- unless they're getting plenty of safe sun exposure. In 2008, the American Academy of Pediatrics recommended that breastfed infants receive 400 IU of vitamin D every day until they are weaned and drink at least 1 liter of vitamin D-fortified formula or whole milk each day. The AAP also recommends 400 IU/day of vitamin D for children and teens who drink less than a liter of vitamin D-fortified milk per day. The Vitamin D Council recommends that healthy adults take 2,000 IU of vitamin D daily -- more if they get little or no sun exposure.”

Vitamin D and multiple sclerosis. (J Cell Biochem. 2008) “Vitamin D is a principal regulator of calcium homeostasis. However, recent evidence has indicated that vitamin D can have numerous other physiological functions including inhibition of proliferation of a number of malignant cells including breast and prostate cancer cells and protection against certain immune mediated disorders including multiple sclerosis (MS). The geographic incidence of MS indicates an increase in MS with a decrease in sunlight exposure. Since vitamin D is produced in the skin by solar or UV irradiation and high serum levels of 25-hydroxyvitamin D (25(OH)D) have been reported to correlate with a reduced risk of MS, a protective role of vitamin D is suggested.”

Greater intake of vitamins B6 and B12 spares gray matter in healthy elderly: A voxel-based morphometry study. (Brain Res. 2008) “In the VBM analysis, we found that adults with greater vitamin B6 intake had greater gray matter volume along the medial wall, anterior cingulate cortex, medial parietal cortex, middle temporal gyrus, and superior frontal gyrus, whereas people with greater B12 intake had greater volume in the left and right superior parietal sulcus. These effects were driven by vitamin supplementation and were negated when only examining vitamin intake from diet. Folate had no effect on brain volume. Furthermore, there was no relationship between vitamins B6, B12, or folate intake on global brain volume measures, indicating that VBM methods are more sensitive for detecting localized differences in gray matter volume than global measures. These results are discussed in relation to a growing literature on vitamin intake on age-related neurocognitive deterioration.”

Inflammation in the vascular bed: Importance of vitamin C. (Pharmacol Ther. 2008) “For endothelial cells, ascorbate helps to prevent endothelial dysfunction, stimulates type IV collagen synthesis, and enhances cell proliferation. For vascular smooth muscle cells, ascorbate inhibits dedifferentiation, recruitment, and proliferation in areas of vascular damage. For macrophages, ascorbate decreases oxidant stress related to their activation, decreases uptake and degradation of oxidized LDL in some studies, and enhances several aspects of their function. Although further studies of ascorbate function in these cell types and in novel animal models are needed, available evidence generally supports a salutary role for this vitamin in ameliorating the earliest stages of atherosclerosis.”

Vitamin B12 deficiency in the aged: a population-based study (Age and Ageing 2007) "Conclusion: undiagnosed vitamin B12 deficiency is remarkably common in the aged, but no specific risk group for screening can be identified. Thus, biochemical screening of unselected aged population is justified. General practitioners play a key role in diagnosing early vitamin B12 deficiency."

NIH - Vitamins

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FDA - Fortify Your Knowledge About Vitamins

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