Few people know that vitamins were discovered by a Jewish researcher who worked in France. Casimir Funk (1884-1967) who was born in Warsaw discovered thiamine when he worked in the Pasteur Institute in Paris. Before coming to the United Statesin 1915. Funk realized that that certain food factors were needed to prevent nutritional-deficiency diseases, such as beriberi (vitamin B 1 deficiency), scurvy (vitamin C deficiency), pellagra ( niacin deficiency), and rickets ( vitamin D deficiency).
Multivitamin supplementation has become a large industry inAmericaand many people believe that taking daily vitamins improves their health and makes them feel better. However, there is no experimental evidence to support this. The large studies that have looked a vitamin supplementation appear to suggest that it helps people who are deficient in specific vitamins but not the people who have an adequate and varied diet. National Institutes of Health says that not enough evidence exists to make a firm recommendation for or against the use of multivitamins for disease prevention.
Why may one not need a multivitamin?
The reason why most healthy people do not need vitamins is that the best source of needed nutrients is a balanced diet. Individual vitamins, even taken together in a pill, may not do inside the body what vitamins taken as food may do. It may be that vitamins are only effective if they combine in specific ways, or come as a complex with or inside other healthful molecules that only food can supply. In addition to vitamins, foods contain a large variety of other healthful substances.
However, vitamins can help people whose health conditions, dietary choices, lifestyle habits or medications impede their bodies’ ability to take in or absorb proper amounts of key nutrients from foods. For example, people over age 60 can often benefit from taking vitamins. Older people may not fully absorb vitamins such as B-12, a nutrient that may reduce the risk of anemia, and vitamin D, which helps maintain bone strength.
How do we know how much is recommended*?
Recommended Daily Intake(RDI) is the daily dietary intake level of a nutrient which was considered in 1968 to be sufficient to meet the requirements of nearly all (97–98%) healthy individuals in each life-stage and sex group. Although the RDI has since been updated, older values are still in use on labels. The RDI is used to determine the Daily Value which is printed on food labels in theU.S.,Canada, andAustralia.
What kind of multivitamin is best?
If you do decide to take vitamins, inexpensive brands that offer the basic vitamin combinations are as good as more expensive options. Labels should indicate that the multivitamin includes 100 percent of the Daily Value (DV) of most essential nutrients. It is not a good idea to take much more than the recommended dose. Remember, you still eat and still take in vitamins from your food and it is easy to take in too much. Large doses (more than the label recommends) of nutrients and extras such as herbs, enzymes and amino acids should be avoided because of possible health risks. Certain vitamins dissolve in water and the body excretes them easily, so taking too much of the water soluble vitamins, such as vitamins C and E is unlikely to be harmful. Other vitamins, such as A and D dissolve in fat and may accumulate in the body over the years, ultimately causing complications.
For premenopausal women, multivitamins with iron can help replenish iron lost during menstruation. Women in our community who are blessed with many children and give birth every few years, should continue prenatal vitamins with iron for at least six months after delivery. Following menopause, iron obtained through diet is usually sufficient.
Do multivitamins supply everything?
Most multivitamin preparation don’t provide the amount of calcium women need. After menopause, women are at a higher risk of developing osteoporosis (bone weakening) and can benefit from additional calcium, especially during and after menopause when bone loss accelerates. After age 50, women should be getting 1,200 to 1,500 milligrams of calcium daily. Calcium is absorbed best when taken several times a day in amounts of 500 milligrams or less.
Women during childbearing years should check with their care provider about taking folic acid, which reduces the risk of spinal cord defects in developing fetuses. Many foods are fortified with folic acid but it may still not be enough for pregnant women.
On May 10, 2010, the International Osteoporosis Foundation (IOF) has released a new position statement on Vitamin D for older adults which makes from an evidence-based perspective. It recommended that the estimated average vitamin D requirement of older adults to reach a serum 25OHD level of 75 nmol/l (30ng/ml) is 20 to 25 µg/day (800 to 1000 IU/day). Intakes may need to increase to as much as 50 µg(2000IU) per day in individuals who are obese, have osteoporosis, limited sun exposure (e.g. housebound or institutionalised), or have malabsorption. For high risk individuals it is recommended to measure serum 25OHD levels and treat if deficient. Based on these recommendations, many physicians routinely prescribe Vitamin D supplementation to their older patients, or patients with chronic disease.
Traditional medicine does not recommend vitamin supplementation indiscriminately. However, vitamins can help those whose circumstances may leave them with an inadequate diet and those whose conditions leave them vulnerable to vitamin deficiency.
*For most common vitamins and minerals, the RDIs are given in the following table, along with the more recent Recommended Daily Allowance (RDA):