“By law, the FDA doesn’t approve dietary supplements or product labeling. The companies that manufacture or market the supplements are responsible for ensuring that their products are safe and lawful,” says FDA spokesperson Courtney Rhodes. Consumers should be aware, Rhodes adds, that companies can introduce new supplements to the market without FDA approval or even notification. That’s because dietary supplements are regulated under different, less stringent rules than those covering conventional foods or drug products. The FDA is proposing stronger regulation of supplements—there’s been little change since 2010—but that hasn’t happened yet.
In the meantime, you should opt for a buyer-beware and buyer-be-informed stance, according to clinical pharmacist Monika Nuffer, Pharm.D., a faculty member at the University of Colorado School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences. Supplement labels, Dr. Nuffer tells SELF, must include the following disclaimer: “This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.” That statement, however, might differ markedly from what supplements manufacturers claim, she cautions. “Manufacturers might include structural or functional claims to market their product. Sometimes those can be misleading, so keep that in mind if it sounds too good to be true.”
The FDA’s Rhodes adds that consumers should be especially wary of product claims such as “works better than [a prescription drug],” “totally safe,” or has “no side effects.” “Throughout the pandemic, the FDA has found many nefarious actors seeking to exploit consumers by selling unproven medical products, often with fraudulent claims,” she tells SELF.
3. Always check with your doctor before starting a supplement.
The main reason for discussing your supplement usage with your provider is safety. Dietary supplements—and that includes vitamins and minerals—can interfere with prescription medications, and taking a larger daily dose than recommended can cause side effects, according to the Mayo Clinic. The same goes for botanical or herbal supplements, says Dr. Grossman.
“My recommendation to patients is to make sure that they share with their health care provider what they are taking in line with over-the-counter products, supplements, or essential oils,” Dr. Nuffer tells SELF. “This is critical to ensuring that the combination of everything is safe. For example, the G herbs—garlic, ginger, ginseng, and gingko—can increase risk of bleeding and bruising if you take them in combination with prescription or over-the-counter blood thinners.”
Another reason to talk to your doctor about supplements is because what your physician doesn’t know about what you’re taking could compromise your care if you do become ill, Dr. Grossman tells SELF. “We know, for example, that approximately 80% of cancer patients use complementary medicine tools, but only 14% communicate this with their traditional practitioners,” she says. “We are also lacking in much-needed research so, fairly, the oncologists are concerned about potential supplement interactions or conflicts with chemotherapeutic and immunologic agents, or radiation therapy.”
4. Know how much you’re supposed to take—and how much you’re actually taking.
Another common misconception about dietary supplements is that if a vitamin or mineral is good for you, increasing your intake might deliver additional health benefits. Rebecca Ruud, M.D., a Bellevue, Wash., internist and associate professor of medicine at the University of Washington, sometimes encounters this view—she calls it “vitaminosis”—in her patients. “They think that if a little bit is good, a lot must be better, but that’s not the case,” Dr. Ruud tells SELF, because the body absorbs only what it needs. Aside from being a waste of money, taking in more than you need can also be harmful.
Too much vitamin D over time can actually weaken the bones, Dr. Ruud notes. Biotin—a popular supplement that people take to improve skin, nails, and hair—can interfere with lab-test results when taken at high levels, making them read falsely high or falsely low, she cautions. Dr. Ruud suspects that many of her patients disclose any supplements that they take, and she always asks about usage. But she also knows that patients often rely on peers’ recommendations regarding supplements, particularly trendy ones like biotin. She recommends that patients who are thinking of using supplements seek reliable information first, like the Mayo Clinic website’s Drugs and Supplements section.