The data, published in JAMA, indicated a decrease in the use of multivitamins from 37% in 1999-2000 to 31% in 2011-2012, which were offset by significant increases in the use of vitamin D and fish oil supplements for the same time periods.
“With the present data, it is clear that the use of supplements among U.S. adults has stabilized. This stabilization appears to be the balance of several opposing trends, with a major contributing downward factor being the decrease in use of MVMM,” wrote the authors, led by Dr Elizabeth Kantor from Memorial Sloan Kettering Cancer Center in New York.
Commenting on the findings, Judy Blatman, Sr VP of communications for the Council for Responsible Nutrition, said: “This new study on dietary supplement trends demonstrates that supplement use is a mainstream and consistent component of consumers’ health care practices, with the majority of U.S. adults indicating they take them. We’re encouraged by the authors’ interest and thoughtful assessment of dietary supplement usage, and are further encouraged that the results show the same steady interest by consumers that we’ve seen in our own market research surveys.”
Dr Kantor and her co-workers analyzed data from 37,958 adults (average age 46) from 1999 through 2012, with the participants surveyed over seven continuous two-year cycles.
Results showed that the use of dietary supplements remained stable between 1999 and 2012 at around 52%.
Multivitamins were not the only class to decline, with decreases also reported for vitamins C, E, and selenium. On the other hand, vitamin D supplement use increased from 5.1% to 19%, and fish oil supplement use increased from 1.3% to 12% over the study period.
Not everyone was encouraged by the usage numbers, however. In an accompanying editorial, Pieter Cohen, MD, of the Cambridge Health Alliance, Cambridge, and Harvard Medical School, Boston, asked: “Why would consumers continue to use supplements after high-quality trials found many of these products to be no more effective than placebos?
“It is now known that many supplements contain pharmaceutically active botanicals, which can have important clinical effects,” added Dr Cohen.
“For example, red yeast rice, yohimbe, and caffeine all have pharmacological effects, and although ephedra has been banned, a variety of synthetic drugs have replaced ephedra as stimulants in many sports and weight loss supplements. Reporting suspected adverse effects of supplements is also critical. The FDA relies on physicians and consumers to report adverse events via MedWatch to remove hazardous supplements from the marketplace.”
“The current study by Kantor et al should also lead funders and legislators to reconsider their priorities with respect to supplements. Given the current regulatory framework, even high-quality research appears to have only modest effects on supplement use. Future efforts should focus on developing regulatory reforms that provide consumers with accurate information about the efficacy and safety of supplements and on improving mechanisms for identifying products that are causing more harm than good.”
CRN: “We hope that healthcare practitioners would take their patients’ interest in supplements seriously”
In response to the comments in the editorial, Steve Mister, CRN’s president and CEO, said: “We absolutely agree with Dr. Cohen that doctors—in fact, all health care practitioners—should be discussing supplement use with their patients. As consumers are demonstrating an increasing interest in integrative health, they also are seeking a more proactive role in managing their own health, and looking for ways to stay well. Physicians must maintain open minds when discussing supplements and consider all the available evidence surrounding the benefits and risks of supplement use.
“Cherry-picking research, dismissing patients’ actual experiences with supplements, and relying solely on randomized controlled trials as the only acceptable validation for benefits all alienate their patients and overlook the robust body of evidence for supplement usage.
“Given that dietary supplement usage is growing in the United States, and research demonstrates that supplement users are more likely than non-users to engage in healthy habits—including visiting their doctors—we would hope that healthcare practitioners would take their patients’ interest in supplements seriously. Physicians should not only discuss potential interactions, but also potential nutrient depletions that result from some medications.
“Physicians should recognize that food comes first, but supplements can complement the American diet. The multivitamin serves to fill in the nutrient gaps that government research repeatedly demonstrates exist, as well as provide critical levels of folic acid and iodine for women of child-bearing age. Physicians should consider that products ranging from glucosamine/chondroitin, protein and Echinacea to omega 3s and probiotics provide consumers with real-life benefits (even if the actual research is mixed) and do so in safer ways than some of the other non-supplement options on the market. We urge physicians to find ways to foster trust between themselves and their patients when it comes to counseling on dietary supplements.”
Ensuring quality, safety, and consumer confidence
Dan Fabricant, PhD, Executive Director and CEO of the Natural Products Association, said: “Consumers are demanding products that compliment their individual health needs, and that’s why a majority of Americans continue to trust and use dietary supplements safely on a daily basis. Addressing consumer confidence and safety is an area that our industry cannot afford to compromise. NPA along with industry leaders recently launched the Supplement Safety and Compliance Initiative to ensure quality, safety, and consumer confidence in every aspect of the production of finished products and the source of their ingredients.”
The study was supported by grants from the National Cancer Institute of the National Institutes of Health.
2016; Volume 316, Number 14, Pages 1464-1474. doi:10.1001/jama.2016.14403
“Trends in Dietary Supplement Use Among US Adults From 1999-2012”
Authors: E.D. Kantor, et al.
2016; Volume 316, Number 14, Pages 1453-1454. doi:10.1001/jama.2016.14252
“The Supplement Paradox - Negligible Benefits, Robust Consumption”
Authors: P.A. Cohen