Vitamins and Dietary Supplements

Cydney E. McQueen, PharmD, on the Benefits and Harms of Supplements

Multivitamins and supplements are widely used in the United States for general health. However, misinformation still exists among both clinicians and patients on their benefits, harms, and regulation practices.

Cydney E. McQueen, PharmD, discussed evidence for the benefits and harms of supplement use at the Nurse Practitioners for Women’s Health 22nd Annual Premier Women’s Healthcare Conference in Savannah, Georgia. Consultant360 caught up with Dr McQueen about her presentation.

Cydney E. McQueen, PharmD, is is an Associate Clinical Professor in the division of Pharmacy Practice & Administration at the University of Missouri-Kansas City School of Pharmacy in Kansas City, Missouri.

Consultant360: What knowledge gaps or misconceptions exist among clinicians and patients regarding supplements?

Dr McQueen: Even many clinicians have a lack of knowledge about how dietary supplements are regulated. Supplements are regulated, but not in the same way or nearly to the same extent as prescription or over-the-counter medications. However, the US Food and Drug Administration, which has legal oversight of these products, does not have the money or man-power to realistically monitor dietary supplement manufacturers and distributors. This means that there are many “supplements” for sale on store shelves or on the Internet that are truly bad or unsafe products. And, that does not even get into the problem of quality – even for supplements that have been shown to be efficacious or safe, not every brand is going to be of good quality or the correct dosage or form.

Many patients believe that supplements will not ever have adverse effects like prescription drugs will. That is simply not the case. It is true that supplements as a whole tend to have fewer and milder side effects, but adverse effects still happen and can be severe. One of the problems in building up a good knowledge base about supplements is that people taking supplements tend to attribute any negative consequences to other reasons, rather than to the supplement itself. This reaction is exactly the opposite of the reaction to prescription medications, which are sometimes blamed for negative occurrences that they have not caused.

Another misconception includes extrapolating the outcomes of animal study results into humans – something that supplement advertisers often take advantage of! If a supplement decreases blood glucose levels in mice and rats, that means more research is warranted. It does not necessarily mean that the same results will be seen in humans.

C360: Who might benefit from supplements, and on the other hand, who might not benefit?

Dr McQueen: The people who might benefit are those who are choosing to take a specific supplement for a specific medical condition, and who have sought appropriate information in order to get the right product, of high quality and in the correct dosage. Anyone taking a supplement “because it is supposed to be good for me,” or to support general health is likely wasting their time, effort, and money, as well as putting themselves at risk of adverse effects. Appropriate use comes down to addressing the known, existing health risks or conditions for each person.  

Here is an example: there are some very interesting epidemiological and research data on lutein and its association with decreased risk for development of macular degeneration. Because lutein has an excellent safety profile, I recommend a lutein supplement, as well as a healthy diet, to individuals with a family history of macular degeneration. Those patients are known have a higher risk of developing the disease. But for individuals without a family history, (i.e., no increased risk), lutein is unlikely to be very beneficial, as far as we know right now. 

C360: What key takeaways do you hope attendees left your presentation with?

Dr McQueen: I would love to see attendees talking to patients more about what patients hope to gain from using a supplement, and using that knowledge to guide them in informed decision-making about that supplement. This can mean deciding not to take it, determining how to pick out a quality product, and/or helping them have realistic expectations about what a good outcome might be for that particular supplement. Helping patients know how and when to stop using a supplement is also very important, and is a piece of the process that is rarely addressed.

—Christina Vogt

McQueen CE. Supplements: harmful or helpful? Presented at: Nurse Practitioners for Women’s Health 22nd Annual Premier Women’s Healthcare Conference; October 16-19, 2019; Savannah, GA.