Nutrition Science and Everyday Application - beta v 0.1

DIETARY SUPPLEMENTS 457
For example, the herbal supplement St. John’s wort makes many medications less
effective.
• The term natural does not always mean safe. Ephedra, an evergreen plant
native to central Asia is associated with heart problems and risk of death. In 2004,
the FDA banned the sale of ephedrine in dietary supplements for these reasons.
Supplements can contain natural herbs and other plant-based ingredients that
have not been adequately studied. We don’t know if supplement ingredients are
dangerous until people end up really sick or even die from them. Dietary
supplements result in an estimated 23,000 emergency room visits every year in the
United States, according to a 2015 study. Many of the patients are young adults
having heart problems from weight-loss or energy products and older adults
having swallowing problems from taking large vitamin pills.
• The term “standardized” (or “verified” or “certified”) on a supplement does
not always guarantee product quality or safety. These are terms used by
manufacturers to sell their product and have not been legally defined.
You can report safety concerns about a dietary supplement through the U.S. Health and
Human Services Safety Reporting Portal. For more information on contaminants in dietary
supplements, visit the FDA’s Dietary Supplement Products & Ingredients webpage.
EFFICACY OF DIETARY SUPPLEMENTS
The amount of scientific evidence on dietary supplements varies widely—there is a lot
of information on some and very little on others. The Center for Complementary and
Integrative Health at the National Institutes of Health offers these key points about efficacy
of dietary supplements: 1
• Dietary supplements can’t be marketed with claims that they can diagnose, treat,
cure, mitigate, or prevent any disease; such claims would require the product to be
approved by the FDA as a pharmaceutical. Instead, dietary supplements are
marketed with health claims or structure/function claims, similar to claims on food
labels. Recall from Unit 1 that structure/function claims (e.g., “builds strong bones,”
or “boosts immunity”) are intentionally vague and require no evidence to support
them. Supplements are often labeled with claims that have little to no scientific
basis.
• Studies have found that some dietary supplements may have benefits, such as
melatonin for jet lag. Others may have little or no benefit, such as ginkgo for
dementia. 1 Many dietary supplements haven’t been studied at all in humans.
• Studies of many supplements haven’t supported claims made about them. For
example, in several studies, echinacea didn’t help cure colds and Ginkgo biloba
wasn’t useful for dementia—but you can still find Ginkgo biloba supplements with
claims that they improve memory and echinacea supplements with claims of
providing “immune support.” Many times the research on a dietary supplement is
conflicting, such as whether the supplements glucosamine and chondroitin
improve symptoms of osteoarthritis. 1 Research design and interpretation can also