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Vitamin and mineral supplements
Sorting fact from fiction
Vitamins and nutritional supplements represent at least a $6 billion-a-year business that continues to grow as people search for a fast and easy ways to stay healthy and feel better. One-quarter to one-third of Americans now take daily vitamin supplements. Seventy percent take nutritional supplements at least occasionally, and one in three people with chronic disease looks to herbal remedies for help.
Although outrageous claims for vitamin supplements have been around for many years, there has been an explosion of "health-enhancing" megavitamins, magic pills and potions since Congress changed Food and Drug Administration (FDA) regulation of "nutritional" supplements in 1994. Virtually every mall in America has a health food store, shelves lined with products that promise to relieve pain, help you sleep better and give your health, vitality and virility a boost.
Now, more than ever, people are focusing on nutrition to help them remain healthy and active. That's good. But do you need vitamin supplements and are they safe?
The answers to these questions are not always clear-cut. There's disagreement within the medical community, as researchers continue to uncover new information about how nutrition affects your health. Further clouding the issue is an almost daily barrage of media reports on new studies some suggesting benefits from supplements, others indicating harm. Then there are those advertisements, promising health in a capsule or in a herbal brew.
Vitamins and essential minerals, also called micronutrients, are needed in tiny amounts to promote essential biochemical reactions in your cells. They are essential for normal growth, digestion, mental alertness and resistance to infection, enabling your body to use carbohydrates, fats and proteins. They also act as catalysts in your body, initiating or speeding up a chemical reaction. However, you don't "burn" vitamins, so you can't get energy (calories) directly from them.
Since your body can't make most vitamins and minerals they must come from food or supplements. Deficiency of a micronutrient for a prolonged period causes a specific disease or condition, which can usually be reversed when the micronutrient is resupplied.
There are 13 vitamins; four are fat soluble and nine are water soluble. Fat soluble vitamins are stored in your body fat and may be stored in certain organs, such as the liver. Most water soluble vitamins are not stored in your body in significant amounts, typically lasting several weeks to several months. (An exception is B12 which may be stored upto 4 years.)
When vitamin supply is adequate your body automatically regulates circulating vitamin levels. Excess water-soluble vitamins are excreted in urine. Surplus fat-soluble vitamins are stored in body tissue. Because they're stored, excess fat-soluble vitamins can accumulate in your body and become toxic. Your body is especially sensitive to too much vitamin A and vitamin D.
Vitamin deficiencies result from either: (1) Inadequate consumption or (2) Biological malfunction in which the body cannot absorb or use the vitamin properly. Either way, not enough is present to carry on body processes. Deficiencies are a three step process:
For example, scurvy is a disease due to vitamin C deficiency that plagued sailors on long voyages for many centuries. The disease, due to inability of connective tissue to form, caused brittle bones and bleeding into the muscles, joints and gums- severe cases lead to death.
Although a relationship between the lack of fresh food and the development of scurvy had been suspected for a long time, it wasn't until 1747 that a carefully planned trial showed that lemons and oranges would prevent the disease. Many sailing fleets subsequently used limes to prevent scurvy; hence sailors became known as "Limeys". It took until 1928, when the science of chemistry was more advanced, for a researcher to identify the substance in citrus fruits and other vegetables. The substance was given the name "vitamin C."
Most vitamins and minerals were discovered this way scientists identifying substances you need because a shortage causes a health problem.
Your body also needs 15 minerals that help regulate cell function and provide structure for cells. Major minerals include calcium, phosphorus and magnesium. In addition, your body needs smaller amounts of chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, zinc, chloride, potassium and sodium. Amounts needed for most of these minerals is quite small and excessive amounts can be toxic to your body.
The answer to this question depends upon your age, health and nutritional status. The question of how much of a vitamin is enough is still debated among scientists and health care professionals.
Initially the FDA published MDA's (minimum daily allowances) for vitamins and minerals. These amounts were needed to avoid diseases seen with specific vitamin deficiencies
In the 1980's this was revised to RDA's (recommended daily allowances). Generally the requirements were increased above the MDA's. RDA's took into account that low levels of certain nutrients, although not low enough to cause a deficiency related disease, might nevertheless interfere with optimal health.
Most recently terminology has again changed to "Percent of Daily Values" or "% DV". This is for an assumed 2000 calorie a day diet. DV's are generally much higher than "minimum requirements".
Recommendations have recently been made to increase the RDA (or DV) for certain nutrients based on recent scientific evidence. Included are:
Vitamin hucksters spend millions promoting fear that you are not getting enough vitamins and minerals. They recommend vitamin, mineral and nutritional supplements as "vitamin insurance." The American Dietetic Association, the National Academy of Sciences, the National Research Council and other major medical societies all agree that you should get the vitamins and minerals you need through a well-balanced diet.
An exception is certain high-risk groups that may benefit from a vitamin-mineral supplement. Persons at risk and current recommendations will be discussed below.
Experts favor food, rather than supplements, because food contains hundreds of additional nutrients, including phytochemicals. Phytochemicals are compounds that occur naturally in foods and may contain important health benefits. Scientists have yet to learn exactly what role phytochemicals play in nutrition, and there's no RDA established for them. However, if you depend on supplements rather than trying to eat a variety of whole foods, you miss out on possible health benefits from phytochemicals.
Vitamin-mineral supplements shouldn't substitute for a healthful diet. However, there's probably no harm in taking a multiple vitamin-mineral supplement with dose levels no higher than 100 percent of the Daily Value. Doses above that don't give extra protection, but do increase your risk of encountering toxic side effects.
There is no need to pay more than four to seven dollars for an inexpensive multivitamin supplement. If manufactured using good quality control a vitamin is a vitamin- it does not matter who makes it. However, it should matter what they charge the consumer. If someone claims to provide custom designed vitamins (usually at a very high price) mad just for you DON"T BUY IT!
At risk persons
Most exaggerated or unfounded health claims occur with megadose supplements. Although knowledge of the toxicities of certain nutrients, such as vitamin A, vitamin D, niacin, and metallic minerals is more common, very high doses of "safe" vitamins are not helpful and sometimes not even safe. Just because a nutrient has beneficial properties in a test tube does not mean it will work in the same way in the body.
The following are examples:
Even modest increases in some minerals can lead to imbalances that limit your body's ability to use other minerals. And supplements of iron, zinc, chromium and selenium can be toxic at just five times the RDA. Virtually all nutrient toxicities stem from high-dose supplements.
Vitamins and minerals are essential micronutrients needed for health and life. They are not miracle cures for aging, poor diet, lack of physical exercise, or lack of motivation to take responsibility for one's physical and emotional well being.
Extra vitamins will not treat anxiety, depression, lack of adequate rest, bad interpersonal relationships or unhappiness on the job.
Modern society is stressful in its own way as less and less of our day is center around meal time and food preparation than it has in the past. However, opportunities for excellent health have never been greater due to increased access to information about healthy habits and increased availability of healthy foods.
Most persons can do their part by eating well and exercising regularly. Certain at risk persons may require an additional supplement; however, it does not have to be expensive nor should it exceed recommended daily values.
Special Thanks to Stephen Barrett, M.D. for his review and constructive input to this page
Doctors Corner INternet Group, Inc. 1997-2004