Almost every day we hear about a new pill or potion promising to add years to your life, give you optimal energy, improve your sex life—or all three. If we believed all the claims, the list of nutrients we need to take daily would be as long as a Jonathan Franzen novel.
It’s hard to sift through the claims and counterclaims, but there are some nutritional supplements health experts know don’t do much good, and may be harmful if you’re not careful about dosages or side effects. Here’s the list of pills and potions you can skip.
Separate trace minerals, such as iron, copper and zinc. Extra iron might be taken to treat anemia; zinc purportedly minimizes cold symptoms (although the results are mixed) and helps with enlarged prostates; and copper supposedly eases rheumatoid arthritis. But these trace minerals are only safe in very small amounts, and it is very easy to overdo them. A few weeks of high dosages won’t hurt you, but a few months could start producing subtle symptoms of toxicity, like fatigue and achiness. Don’t take more than the recommended allowance of these trace minerals without medical supervision.
Extra folic acid. This B vitamin is now added to foods such as bread and breakfast cereals. As a result, most people now get the 400 micrograms they need daily. Excess folic acid has been considered mostly harmless, but recent research suggests that amounts higher than 800 micrograms might promote the growth of cancer. Don’t take more than the amount in a typical multivitamin–400 micrograms. You mayneed additional folic acid if you abuse alcohol or take anti-seizure medications, since both deplete the body of folic acid. Women planning to become pregnant should talk with their doctor about folic acid supplementation prior to becoming pregnant.
Preformed vitamin A. In third world countries, preformed vitamin A (listed on supplement labels are retinyl palmitate and retinyl acetate) is a lifesaver against infection and blinding eye disease. But in the U.S., many researchers now think people get more vitamin A than they need from fortified foods, especially breakfast cereals, and supplements, including multivitamins. That’s not good, because new research suggests thatgetting even a little too much vitamin A can promote osteoporosis. That effect can happen even with the amounts of vitamin A some manufacturers put into a multivitamin. Your best bet is to get no more than 750 micrograms (2,500 IU) of preformed vitamin A a day from foods or supplements. Get most of your vitamin A instead from beta-carotene, which can convert to vitamin A in your body as needed. Look for a multivitamin that has at least 50 percent of vitamin A from beta-carotene.
Cod liver oil. Years ago, this fishy oil was a lifesaver for many, with its rich mix of vitamins A and D and omega-3 fatty acids. Nowadays, though, cod liver oil has fallen out of favor. It becomes rancid very easily, making it decidedly unhealthy, and some brands contain too much vitamin A, or environmental toxins. Opt instead for omega-3s from molecularly distilled fish oil, vitamin D from a separate supplement, and vitamin A as beta-carotene from a multivitamin, as described above.
Separate vitamin E. It’s OK to get 200 to 400 IUs of vitamin E from a multi-vitamin. But research seems to suggest that taking large doses (more than 400 IUs) of vitamin E is not helpful for heart disease or cancer prevention, contrary to what was thought in the late 1990s. In fact, more recent research suggests that higher doses of vitamin E may actually interfere with blood clotting or disrupt the balance of other antioxidants and fat-soluble vitamins. Still, most people could stand to get healthy, smaller amounts of vitamin E from foods. Best way? Eat fresh nuts such as almonds and hazelnuts, avocadoes, and use unrefined nut and vegetable oils.
St John’s wort. This herb used to be a popular alternative treatment for depression. It does work for mild to moderate depression, but it has been found to have many side effects, causing it to fall out of favor. Side effects include adverse interactions with a long list of drugs; and sun sensitivity, increasing your chances of getting badly sunburned.
Green tea extract. Green tea extract (usually a concentrated form of one of its active ingredients, EGCG) is used for everything from weight loss to cognitive enhancement to cancer prevention, without much proof of benefit. In contrast, there are quite a few studies suggesting that drinking green tea can be beneficial to your health in many ways. In your mouth and throat, direct contact with the beverage may reduce the risk for oral and esophageal cancer. Green tea has many more active ingredients than just EGCG, and some of them show surprising health benefits. So go with the tea—not the pills, and drink about three cups a day for maximum benefits.
High-dose vitamin C. Research suggests that high dose vitamin C (about 3,000 milligrams a day) can reduce the duration of a cold by about 1.5 days, or reduce the likelihood of catching a cold in highly stressed people. But most people simply do not need more than a couple of hundred milligrams of vitamin C a day. In fact, the more they take, the harder their bodies have to work to get rid of it. Long-term use of high-dose vitamin C has been linked to kidney stones. Stick with no more than 200-500 milligrams a day, and crank it up to 3,000 milligrams-plus for no longer than 10-14 days for a cold.
Growth hormone-releasing supplements. Since actual growth hormone is available only by prescription, and illegal for use in professional athletes, supplements that stimulate the body’s natural muscle-building growth hormone are popular with body builders and anti-aging fanatics. They may include lots of different ingredients, including amino acids such as arginine, lysine and ornithine, hormone precursors such as DHEA and GABA, even some glandulars (derived from animal glands.) But even the web sites that sell these products admit that you can stimulate growth hormone even better yourself with high-intensity exercise. Getting enough sleep also stimulates growth hormone release.
Topical (applied to the skin) supplements. There simply is not good, independent research to show that topically applied nutrients are absorbed through the skin in amounts significant enough to do much good. That’s especially true for the arthritis supplement, glucosamine sulfate, which is a large molecule that has a hard time even getting through your intestinal tract. Capsaicin (pain-relieving hot pepper cream) is one exception. But it is not getting into the bloodstream, it is simply affecting nerve cells in the skin.