The majority of adults in the US take at least one dietary supplement, according to the National Institutes of Health—and spend nearly thirty billion dollars per year on vitamins, minerals, herbals, botanicals, amino acids, and/or enzymes in the quest for better health, vitality, energy, longevity. Many want to fill in the nutritional gaps in their diets. But are they worth the money? Are they doing any good? Or any harm?
Most people maintain the belief that taking a supplement can’t hurt, even if it doesn’t do much good. But research shows that’s not necessarily true. According to an article posted by Harvard Health Publications, St. John’s wort can decrease the effectiveness of certain prescription drugs, including antidepressants and birth control pills. Other supplements can affect how your body bleeds and interacts with anesthesia. High amounts of vitamins A, C and E and beta carotene can increase the risk of cancer and other diseases by excessively inflating the concentration of antioxidants in the body. Though these are extreme examples, they serve to reinforce that it’s important to let your health provider know which supplements you’re taking. Especially since an increasing number of foods and beverages are fortified with supplements; you may already be getting more than you’re aware, and you may not know how your supplements will react to other medications.
It’s also important to note that:
- While the FDA has established “good manufacturing practices” and periodically inspects the facilities where supplements are made, the FDA doesn’t regulate their purity, potency, safety, or efficacy. It can eventually take action if products are “adulterated, misbranded, or likely to produce injury or illness”—but only after they’re on the market and shown to be harmful.
- The Office of Dietary Supplements (ODS) does not test, analyze or rate dietary supplements, either.
- Manufacturers aren’t required to make accurate or truthful claims about what their supplements can do.
- No human research is required to prove supplements are safe and/or effective before they’re marketed.
- There’s a great deal of false and misleading advertising alongside these products.
- Some manufacturers use the terms “standardized” “verified” or “certified”, but U.S. law does not define standardization; these terms don’t necessarily guarantee product quality.
So what can supplements do—and is there any reason to take them?
Since the days of rickets and scurvy, people have sought out the countless benefits of vitamins. People like taking supplements because they feel like they’re making a simple, proactive step to improve their health. And some supplements really do have benefits.
According to the NIH “Scientific evidence shows that some dietary supplements are beneficial for overall health and for managing some health conditions. For example, calcium and vitamin D are important for keeping bones strong and reducing bone loss; folic acid decreases the risk of certain birth defects; and omega-3 fatty acids from fish oils might help some people with heart disease.”
The following is a list of supplements worth considering:
Vitamin D: About 70% of Americans don’t get enough vitamin D. And since oily fish and fortified dairy products are the only real dietary sources, these supplements make sense. A blood test will confirm whether your levels are low. For kids, taking vitamin D supplements can reduce the chance of catching the flu, and for older adults, they can improve bone health and reduce the incidence of fractures.
Calcium: Many people don’t consume enough calcium-rich foods to meet their daily requirements, so these supplements could be beneficial—particularly women, who are at a higher risk for osteoporosis.
Vitamin B12: Strict vegetarians may need these supplements, since vitamin B12 is only found in animal-based foods. Many people make up for this limitation by eating fortified grains; but, if your grains consumption isn’t consistent, a supplement might help.
Fiber: Whole grains, fruits, vegetables, nuts, and seeds are the best sources of fiber, but many people need to supplement their diets to get the recommended amount.
Omega 3 fatty acids: According to a recent article in Scientific American, “there’s no question that polyunsaturated omega-3 fatty acids—the technical name for the good fats found in fish and fish oil—are important parts of a healthy diet. Our bodies can’t make them, yet we need them to survive, as they form part of our cell membranes. Research suggests that they reduce blood pressure and inflammation and that they increase brain blood flow and give neurons structural strength.” Be sure to avoid fish liver oil, however, which is high in Vitamin A.
Probiotics: The trillions of bacterial cells that live inside us are crucial in regulating our digestive health; so if a course of antibiotics wipes them out, it makes sense to replace them with a probiotic or a food rich in bacteria, like yogurt.
Zinc: Study after study “has shown that vitamin C does nothing to prevent common cold, a misbelief that dates to a theoretical suggestion made by a scientist in the 1970’s.” But zinc on the other hand, actually does.
Niacin: A 2010 review found that for people with heart disease, taking daily Niacin supplements reduced their chance of a stroke or heart attack.
Garlic: When taken as a concentrated supplement, garlic is effective in combating high blood pressure.
Of course while these supplements can be beneficial, “Pills are not a shortcut to better health and the prevention of chronic diseases,” says Larry Appel, M.D., director of the Johns Hopkins Welch Center for Prevention, Epidemiology and Clinical Research. “Other nutrition recommendations have much stronger evidence of benefits—eating a healthy diet, maintaining a healthy weight, and reducing the amount of saturated fat, trans fat, sodium and sugar you eat.”
But if you’re curious about which supplements are proven to be beneficial or harmful, this guide can be helpful.
Supplements and Pregnancy
The National Institutes of Health (NIH) warns that many dietary supplements haven’t been well tested for safety in pregnant women, nursing mothers, or children—so be careful about which you ingest or give to your children. Beyond that, though, pregnant women are often advised to take two supplements. Folic acid to lower the chance of birth defects, and omega-3s to boost fetal brain development. The Centers for Disease Control and Prevention recommends that all women of reproductive age get 400 micrograms of folic acid daily; the benefits of omega-3s have “been clearly demonstrated in trials,” says Dariush Mozaffarian, a cardiologist and epidemiologist at Harvard University, who studies fish oil.
Supplements for Athletes
Many athletes use supplements to get a competitive edge, to replace what’s been depleted, to change their body, or to augment their dietary intake: so which ones are worth the investment?
Caffeine: “Studies have shown repeatedly that you can get improvements in performance, mainly in endurance-type exercise, with caffeine,” says Janet Rankin, PhD, professor in human nutrition, foods, and exercise at Virginia Tech. Because caffeine is available in energy drinks, tablets, gum, sport gels, and sprays, be sure you read the labels regarding dosage—you shouldn’t take more than 400 milligrams a day. “You don’t need all that much caffeine to get the effect,” Rankin says. “And it is possible to overdo it.”
Creatine: “For very short-term bouts of exercise, creatine supplementation seems to aid in recovery,” says Thomas Sherman, PhD, professor in pharmacology and physiology at Georgetown University Medical Center in Washington, DC. But, if you eat a diet including beef and pork, you may not need the supplement, which some studies have shown to increase fat and not muscle. Also be aware that high doses of creatine may cause kidney, liver, or heart damage, though the optimal range hasn’t been proven.
Beta-Alanine: Athletes take beta-alanine to ease the muscle burn of lactic acid buildup. “Some studies show a benefit. Others don’t,” Rankin says. “We need more studies on it, but it’s not one that I’m worried about people trying.”
Branched Chain Amino Acids: While these supplements might work to help athletes bulk up, they won’t provide dramatic results. “Exercise stimulates muscle [growth] anyway. [T]aking amino acids probably isn’t physiologically very significant, but it’s also not harmful,” Sherman says.
Whey Protein for Muscle Growth: “There’s a window of about at least 30 minutes after you stop exercising during which you can take in protein and promote [growth] of lean muscle mass,” Sherman says. But a high-protein meal after a workout would likely give you the same results.
Basically the research says that few supplements are likely to help, some may actually be harmful, and most will just be a waste of money—though they might provide a pleasant placebo effect. Keep in mind that no dietary supplement can make up for not taking care of your heath, and that it’s important to disclose any supplements you take when you see your doctor to be sure they complement any other medications she prescribes.