Do we all need supplements that the supplement industry tries to sell us? Probably not. Study after study fails to support the notion that dietary supplements are needed for enhanced health or longevity by most healthy people.
If you are deficient in a particular nutrient, then perhaps a multivitamin/mineral supplement would alleviate that deficiency. For example, if you have low intakes of fruits and vegetables, you may need some extra vitamin C for optimal nutrition.
Reliance on dietary supplements can give you a false sense of security about your health. Foods contain other nutrients called phytochemicals that work together with vitamins and minerals that cannot be delivered in a supplement.
There are some risks, especially with supplements that provide doses over the RDA. If the label boasts descriptions of “mega”, “advanced formula”, “high potency”, and “ultra”, stay away and save your money. However, if your doctor has determined with laboratory tests that you are deficient, pay attention to his/her advice on diet supplementation.
Another consideration is that dietary supplements are not regulated or tested for safety and efficacy by the FDA as are prescription drugs. There is little attention paid to their purity or how much of the active ingredients are present, i.e. little quality control.
As for the risks:
- People who smoke should not take beta-carotene.
- People unable to regulate iron absorption should avoid supplements containing iron. Iron can accumulate in the heart and lead to a condition called hemosiderosis or hemachromatosis, especially in older men.
- People prone to kidney stones should avoid high dose vitamin C supplements.
- People who take certain medications should be cautious because some interact with supplements; e.g. taking vitamin E or vitamin K supplements can alter the effectiveness of anticoagulant medications. Check with your doctor. Source: Smolin and Grosvenor, Nutrition: Science and Applications, Third Edition.
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