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Establishing the Right Role for Vitamins: Best Approaches with Patients —Commentary

08/21/17 Larry E. Johnson, MD, PhD, University of Arkansas for Medical Sciences|University of Arkansas for Medical Sciences;

Vitamin D seems to be having its moment in the sun. Physicians may have witnessed a recent surge in the number of patients requesting lab tests to determine their vitamin D-3 levels. It’s the fifth most common test under Medicare, and the frequency of those tests increased 83-fold from 2000 to 2010.

The public’s increased interest in vitamin D has undoubtedly been driven by countless media stories touting its benefits over the past decade or so, including reducing the risk of depression and upper respiratory tract infections. Much of this research has been misinterpreted or inconclusive, but that’s done little to slow the demand for vitamin D supplements.

For physicians who have been practicing for a few years, all this may feel familiar. Several vitamins have experienced periods of heightened popularity, beginning with Linus Pauling’s unfounded claims on the benefits of vitamin C. Vitamin E experienced similar hype in the 1990s, when early reports suggested it could prevent prostate cancer in men. In fact, the Selenium and Vitamin E Cancer Prevention Trial found a statistically nonsignificant increase in prostate cancer risk in subjects taking a vitamin E supplement.

Today, vitamin D is riding the same wave, being branded as an easy path to better health that doesn’t involving significant lifestyle changes. While patients may seek out nutritionists or dietary specialists to pose questions about vitamin intake, family practice physicians and certain specialists should also be prepared to discuss the benefits and downsides of supplementing—and temper patients’ expectations.

Treatment considerations

The Recommended Dietary Allowances (RDAs) from the Institute of Medicine is the best source for unbiased guidelines that physicians can share with patients to make sure they aren’t taking potentially harmful quantities of vitamins. It’s also important to note that vitamins may interact with specific medications, particularly when vitamins are taken in high doses. Vitamin E, for example, can cause bleeding when the patient is also taking an anticoagulant such as warfarin.

Other patients with specific conditions or dietary habits may be more likely to need to supplement their diets to reach RDAs for specific vitamins. Vegans and lactose-intolerant individuals, for example, are more likely to benefit from calcium or vitamin D and vitamin B12 supplements. Individuals over the age of 70 may also need to supplement their diets with vitamin D to reach the RDA of 800 IUs. Patients with short bowel syndrome or an inflammatory bowel disease typically require a multivitamin, depending on their condition and diet. Patients who have undergone bariatric surgery may also need to take additional vitamins, and it usually falls to the primary care physician, rather than the surgeon or nutritionist, to ensure RDAs are being met long-term. Finally, patients with alcoholism may also benefit from a multivitamin.

Multivitamins: What’s the harm?

For generally healthy patients who eat a decent diet, a daily multivitamin is not usually necessary. However, many patients will essentially ask, “What’s the harm?” A simple multivitamin has very few adverse consequences, however more and more research also points to few long-term benefits.

Instead, physicians should point to positive lifestyle factors—a healthy diet, exercise, moderation in drinking alcohol, and not smoking. These lifestyle changes will have a far greater impact on a person’s health and energy levels than a daily multivitamin.

Getting patients on the same page

Convincing patients to shift their focus away from products marketed as silver bullets for health is a considerable challenge. Vitamin supplements is a $14-billion industry that often tells patients that physicians don’t have interest or knowledge in the potential benefits. Patients may not even tell their doctors what supplements they’re taking for fear of being dissuaded.

Of course, physicians must be informed of everything a patient is taking, prescribed or not. It’s therefore critical to facilitate conversations about the patient’s conditions or motivations for considering vitamin supplements. It’s often effective to focus on the monthly cost of vitamins compared to other activities that can improve long-term health.

Squeezing these conversations into a 15-minute office consultation can be a challenge, and it can be difficult to set expectations with patients that many of the most effectively-marketed treatments may not deliver real results. Ultimately, a patient’s interest in vitamin levels and supplements demonstrates an interest in making healthy choices and improving long-term outcomes. However, for a vast majority of patients, encouraging them to live a healthy lifestyle is a better approach. Physicians can refer patients to the consumer chapter of the Manual on vitamins for more information.