According to the National Institute of Health, the body needs 13 vitamins for normal health. These include vitamins A, C, D, E, K and the B complex (thiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B 6, B 12 and folate. Each of these vitamins provides various functions for the body. Under normal circumstances, a person can obtain all of the vitamins he needs from eating a well balanced diet.
Vitamins are classified primarily as to solubility. Some are soluble in fat and some in water. Vitamins that are fat soluble are stored in the body and can accumulate. Water soluble vitamins are flushed out by the kidneys. Additionally, some classify vitamins as to whether they were obtained naturally from food or from supplements. However, this becomes somewhat complicated as many foods are vitamin fortified.
Vitamin A, D, E and K are stored in fat and liver cells in the body. Vitamin A is important for vision, especially night vision, bone growth and mucous membranes. As an antioxidant, it may reduce the risk of some forms of cancer. Vitamin D aids in the absorption of calcium and phosphorous. Teeth, bones and cartilage require it. Vitamin E is also an antioxidant and helps to generate red blood cells and prevents blood from clotting. Vitamin K also works with the blood, aiding in the normal clotting process and bone maintenance.
The B-complex vitamins and C are water soluble. As such, they are not stored in the body and need to be replenished daily. The B-complex vitamins assist the body in obtaining energy from food, vision, appetite control, healthy skin, nervous system and blood cell formation. C vitamins aid in growth of tissues, cartilage, bones, teeth and wound healing. Vitamin C also aids the white cells in helping to break down bacteria.
The best way to provide your body with all of the vitamins it needs is to eat a well rounded healthy diet. For individuals with specific health problems, a daily vitamin may be recommended by their physician. Pregnant or breastfeeding women may also have daily vitamins recommended by their physicians. Individuals who are on strict diets or follow a vegetarian or vegan diet may supplement their intake with a multiple daily vitamin as well.
Risks of Supplementing
For the average person, taking one multiple vitamin daily that meets the recommended dosage is not harmful, although it may not be needed. However, taking large doses of any vitamin, particularly fat soluble vitamins may have a toxic effect on the body.