Olugbenga Obasanjo, MD, MPH, PhD, CPH


October 27, 2011

In This Article

The Clinical Encounter

With an estimated 50% of the US population using dietary supplements, it is imperative that the clinician always ask about dietary supplements during the clinical encounter. This is particularly important during early encounters when the patient care dyad is being established. The clinician should clearly ask about vitamins, minerals, and botanicals and encourage patients to bring their dietary supplements to clinic visits. The US Preventive Services Task Force recommends including questions about supplement use in the patient education and counseling for prevention section of the clinical encounter.[8]

Clinicians who have regular interaction with patients need to be up to date on current dietary supplement usage patterns in the clinician's patient pool and in the United States in general. NHANES collects the most comprehensive data on supplement use, and studies using NHANES data are likely to provide the most accurate, representative information. A search on PubMed or Google will produce several articles and journals on dietary supplement use patterns among various populations and subgroups in the United States and elsewhere.

The FDA regulates dietary supplements far less stringently than it regulates pharmaceutical drugs. As a result of this disparity in regulation, patients could be taking supplements that have unreliable amounts of the active ingredient or those that are adulterated with impurities. Certain geographic areas of the world may be associated with specific patterns of contamination. It is essential, therefore, to understand not only the epidemiology of supplement use patterns but also the sources of the supplements used by the population in order to identify possible side effects or contaminants.

The clinician should use the clinical encounter to inquire about supplement use and take the opportunity to discuss the benefits and risks of supplements, when/whether they should be taken, and how they compare with prescription and over-the-counter medications. On the basis of the medical history, the clinician should determine whether supplement use is an important issue for a certain patient's health. For example, appropriate supplement use should be discussed with patients for whom the following situations apply:

  • Consuming fewer than 1600 calories per day;

  • Vegans, vegetarians, and anyone eliminating an entire food group from their diet;

  • Pregnant and breast-feeding women;

  • Postmenopausal women and those with heavy menstruation;

  • Chronic diarrhea;

  • Food allergies and food intolerances; and

  • Surgical removal of portions of the digestive tract or bariatric bypass surgery.

Additionally, oncology patients should be warned about the possibility that antioxidative supplements, such as vitamins C and E, can interfere with anticancer medications.

One way to become aware of potential issues with supplement use is through health information technology. Not only can numerous educational programs on supplements be found online, but many search engines also can cross reference different types of medicines, and many of them can easily check for interactions between supplements and other medications. Most office electronic medical record (EMR) systems have software that flags interactions between active ingredients in drugs and supplements. However, given the variability of dietary supplements in the marketplace, EMRs are not foolproof.


EHR Vendor Comparison

Reporting Serious Problems to US Food and Drug Administration MedWatch: Reporting by Health Professionals

WebMD: Protect Your Health -- Vitamins and Supplements

WebMD Drugs & Medications A-Z: Find a Dietary Supplement by Name

Medscape Reference: Drug Interaction Checker


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