When it comes to supplements, more is not always better.
Too much of a good thing?
Vitamins and minerals are essential to health, but that doesn’t mean that megadoses will keep you out of the hospital or make you live longer. Some may be harmful. In most cases, it’s preferable to get these nutrients from a balanced diet. High doses of certain vitamins and minerals may be appropriate for certain people, though. Talk to your doctor about supplements if you are a woman of childbearing age, are a vegetarian or vegan, have limited exposure to the sun, are an athlete in training, or suspect for any reason you may be malnourished. Here’s the lowdown on eight common supplements—most of which are vitamins you probably don’t need.
For most healthy adults, the recommended daily allowance of beta-carotone (in the form of vitamin A) is 3,000 IU for males and 2,130 IU for females. Some of its highest food sources include carrots, spinach, kale, and cantaloupe. Some people take is as an anti-cancer antioxidant, but the supplements can actually increase risk of lung cancer in smokers (learn how to notice symptoms of lung cancer) and hasn’t been shown to prevent any other form of cancer. Bottom line: Don’t take it. Don’t miss these other vitamin mistakes you’ve been making.
Aim to get 400 micrograms of folic acid, found in fortified bread and breakfast cereal, legumes, and asparagus, every day. Because it’s been shown to reduce the risk of neural tube defects in newborns, some women take it while pregnant. But some doctors warn supplementation of food with folic acid could be fueling rising rates of colon cancer. Bottom line: Only women who are pregnant or may become pregnant are advised to take it. If you’re a mom-to-be, you’ll relate to these thoughts every woman has with a positive pregnancy test.
Aim to get 55 micrograms of selenium from natural sources, like Brazil nuts, tuna, and beef. Some people take selenium to prevent cancer, especially prostate cancer. But those good intentions could actually be working against you—one major study found that taking selenium could actually increase risk of high-grade prostate cancer in men who were already high in the mineral. (One real prostate cancer prevention? Ejaculating. Find out how many times to ejaculate every month to cut cancer risk.) Selenium could also be one of the worst supplements for diabetes. Another 2007 study found a 50% increased risk of type 2 diabetes in people who took 200 micrograms a day. Bottom line: Don’t take it.