

You are reading Part 3 of 4 in this series. What are Quick Facts?
Most American adults report taking vitamins, minerals, or other dietary supplements, but assessments of supplements’ potential benefits and risks are complicated by many scientific and regulatory factors. Although some of these dietary supplements are recommended by doctors for populations at risk of specific nutrient deficiencies, there is little evidence that supplements benefit generally healthy people.
How are supplements regulated?
- Unlike prescription drugs, supplements are not evaluated for approval by the Food and Drug Administration (FDA) and companies are not required to submit safety and efficacy data prior to marketing them.
- Instead, supplements are regulated by the FDA under the Dietary Supplement Health and Education Act, which holds that for all new dietary ingredients introduced after Act took effect in October of 1994, manufacturers must provide information showing why they are “reasonably expected to be safe.”
- The types of information that can satisfy this requirement are broad and vaguely defined. They include: how much of the new ingredient is present in the product, information about the ordinary conditions of the ingredient’s use, and a history of use or other evidence of the ingredient’s safety.
- For manufacturers that introduce new supplement products containing “old” ingredients (that is, dietary ingredients that were in the food supply prior to the Act taking effect), these rules do not apply.
- Manufacturers are not required to test new supplements in clinical trials that would reliably identify benefits or risks, including potentially dangerous interactions with other drugs. As a result, advertised benefits are often based on limited and often low-quality evidence.
- By law, supplement companies cannot explicitly claim that their products cure, treat, or prevent disease. Only FDA-approved drugs, which are required to undergo rigorous scientific evaluation, can make such claims.
- Instead, supplement companies can make claims that describe “the role of a substance intended to maintain the structure or function of the body.”
- For example, a manufacturer can claim that its multivitamin “promotes” or “supports” heart health, even if there is no specific evidence to substantiate that claim, and as long as the statement is accompanied by the following disclaimer: “These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.”
How are supplement regulations enforced?
- The FDA has issued guidance to manufacturers describing its expectations for manufacturing practices, but in practice enforcement relies on after-the-fact reporting by consumers, health care providers, or supplement companies when problems arise. On its website, the FDA lists its “Current Good Manufacturing Practice” for dietary supplements as containing nonbinding recommendations, and notes that its “Dietary Supplement Labeling Guide” does “not establish legally enforceable responsibilities.”
- The FDA has the authority to remove supplement products from the market if they are found to be unsafe or if they are found to make false or misleading claims, but it can take years for the FDA to accumulate sufficient data to justify a product recall or ban.
- The FDA received more than 15,000 self-reported descriptions of health problems with suspected links to supplements, including 339 deaths and nearly 4,000 hospitalizations, between 2004 and 2013 .
- The FDA has issued warning letters to companies that promote supplements as “cures” for Alzheimer’s disease, opioid addiction, cancer, and other ailments. However, some products carrying those claims continue to be sold due in part to the ease with which companies can rebrand and update their marketing strategies.
- The Federal Trade Commission (FTC) regulates the advertising of supplements in marketing materials, such as print, broadcast, and online ads, although it generally defers to the judgment of the FDA. The FTC’s standards mandate that ads are truthful and substantiated, but it does not approve ads in advance.
Basics:
- The National Institutes of Health (NIH) Office of Dietary Supplements has information on specific supplements and answers some common questions about supplements. The U.S. National Library of Medicine offers some key definitions related to vitamins.
- PubMed is a searchable database of biomedical literature. It’s essential for finding the latest published evidence on specific supplements.
- A 2018 JAMA article, Vitamins and Mineral Supplements: What Clinicians Need to Know, highlights drug interactions, safety concerns, and potential benefits.
- The U.S. Department of Agriculture collects informational pages from different government, academic, and scientific institutions on a number of different vitamins and minerals.
- The Food and Drug Administration (FDA) offers a chart listing the functions, daily values, and sources of various vitamins and minerals. The FDA also outlines “What You Need to Know About Dietary Supplements,” and provides a list of resources for consumers that gathers fact sheets, updates, and information from other agencies.
- Nature Endocrinology’s 2016 review article details the relationships between supplements and health impacts in both developing and developed countries.
- A 2015 investigation in JAMA Internal Medicine revealed results from nearly 12,000 adults in the National Health and Nutrition Examination survey, addressing reasons for supplement use. A 2016 investigation in JAMA explores trends in supplement use as shown by responses to the same survey from nearly 38,000 adults.
- Some dietary supplements have been found to be contaminated or even harmful. Some herbal medicines contain heavy metals or pesticides, according to this 2011 study from Science of the Total Environment, although most did not have concerning concentrations. A U.S. Preventive Services Task Force statement found harms linked to several supplements.
- The NIH details its priorities for investigating the biological activity tied to complex natural products, including a strategic plan with tenets that include advancing research, preventing disease, and improving care.
- A 2020 Journal of Nutrition analysis discusses the state of science surrounding personalized nutrition, including the use of data analytics and diet interventions adapted to individuals’ behavior, genetics, and health.
Regulation and Recommendations:
- The FDA offers a detailed account of its guidance and regulation for dietary supplements, and a drug adverse event report browser from the FDA includes information on supplement-related incidents.
- A 2015 article from the journal Drug Testing and Analysis delves into the impact of the Dietary Supplement Health and Education Act on regulation and consumption of herbals and other medicinal products, outlining safety concerns and efficacy concerns in the supplement market today.
- Problems with supplements are tracked by consumer watchdog organizations Center for Science in the Public Interest and Consumer Reports.
- The FDA commissioner released a statement in February of 2019 discussing efforts to strengthen oversight of the dietary supplement industry.
- The NIH website houses the latest reports on Dietary Reference Intakes. A 2016 article, History of Nutrition: The Long Road Leading to the Dietary Reference Intakes for the United States and Canada in Advances in Nutrition details how DRIs are created and applied.
- The U.S. Department of Agriculture’s Dietary Guidelines for Americans, Eighth Edition contains information about foods’ nutrient content.