“The belief is that they [dietary supplements] are entirely safe,
but now science says that they’re not.”
– Pieter Cohen, MD, Harvard Medical School
A recent study of 63 hospitals from 2004 to 2013 estimated that over 20,000 ER visits and 2000 hospital admissions annually in the U.S. were due to adverse effects of dietary supplements. Adverse events included allergic reactions, excess doses, unsupervised ingestion by children, or other events (e.g., choking). Cases involving death, intentional self-harm, drug abuse, or withdrawal were excluded. Adverse effects commonly involved cardiovascular adverse effects from weight-loss or energy herbal products among young adults, unsupervised ingestion of micronutrients (iron) by children, and swallowing problems associated with micronutrients (multi-vitamins) among older adults. (1)
The supplements listed included orally administered herbal products (Echinacea, Coenzyme Q10, Gripe Water, etc.), complementary nutritional products (fish oil, body building protein , chondroitin/glucosamine, etc), vitamins and minerals (including calcium and iron), and topically administered herbal or homeopathic products. Energy drinks and herbal tea beverages were excluded from the study.
In the U.S. there were more than 55,000 dietary supplements on the market in 2012, and about half of all adults reported having used at least one dietary supplement in the past month. 150 million people in the U.S. take supplements, including children’s vitamins. In 2007, out-of-pocket expenditures for herbal or complementary nutritional products reached $14.8 billion, which equaled one-third of the total out-of-pocket expenditures for prescription drugs.
- Weight loss supplements or herbal energy products led the list of supplements with adverse effects in this study.
- More than half of emergency department visits for supplement-related adverse events involved female patients.
- Sexual-enhancement products or bodybuilding products were implicated in 14% of emergency department visits for supplement-related adverse events among male patients; there were too few cases among female patients to calculate a reliable estimate.
- 20% of ER visits involved children who took supplements without supervision.
- Most ER visits for unsupervised ingestion of supplements by children involved multivitamins (34%), iron (12%), supplements for weight loss (11%), and supplements for sleep, sedation, or anxiety (9%). Child-resistant packaging is not required for dietary supplements other than those containing iron (the amount of iron in the usual bottle can be lethal to small children) , but despite such packaging, iron supplements were the second most commonly implicated type of supplement in unsupervised ingestion by children.
Although the numbers of ER visits and hospitalizations were less than the 5% of the ER visits that have been reported for pharmaceutical products, dietary supplements are unregulated and marketed under the presumption of safety. The FDA is actually BARRED from regulating dietary supplements by the Dietary Supplement Health and Education Act of 1994. (Wouldn’t you like to know the history of that particular bill, or at least, the lobbyists involved?)
When you or someone you know has a good effect from a supplement (like taking glucosamine for knee pain) it natural to think that anyone with knee pain should take it, and that every physician should know about this “miracle supplement”. In medicine that kind of anecdote is called a “case report”. Case reports can lead to studies of a large number of people, called “statistical studies”. Results of those studies can be persuasive, but the truly scientifically skeptical physician will wait for the results of an organized, randomized, double-blind study with controls (people who don’t get the supplement). Such organized, controlled studies have not found a whole lot of benefit, if any, from taking dietary supplements, especially vitamins, but that is the subject for another whole blog… or two.
1. Emergency Department Visits for Adverse Events Related to Dietary Supplements
Andrew I. Geller, M.D., et al, N Engl J Med 2015; 373: 1531-1540; October 15, 2015