Scientists must speak out against misinformation about "immune-boosting" supplements

Dietary supplements can be dangerous, despite what social media influencers say


Photo by Michał Parzuchowski on Unsplash  

The COVID-19 pandemic saw huge increases in searches for immunity boosters, including for things like supplements claiming to improve immune function. But even before COVID-19 scared people into their nearest supermarket aisle, "wellness" through supplements was a multi-billion dollar industry. Celebrities and influencers across social media platforms regularly advertise and promote a myriad of supplements to improve health and the immune system. However, there are some major problems with these claims — namely, vitamin companies are not regulated by the Food and Drug Administration (FDA) as drugs, and many supplements don't work as claimed

Unlike pharmaceuticals, which must undergo clinical trials that are reviewed by the FDA for the product's safety and efficacy, dietary supplements have a less stringent path to market shelves. Even though they are most often found in or next to the store pharmacy, dietary supplements are regulated as food, not as drugs. This means that they have not been evaluated or proven effective. Furthermore, while the manufacturer must prove the ingredients are "reasonably safe", none of these products are formally "approved" by the FDA. But these supplements are not always inherently harmless options for people trying to live a healthy lifestyle. A 2015 study concluded adverse effects from dietary supplements caused an "estimated 23,000 emergency department visits in the United States every year." 

Despite these risks, there has been an unfortunate absence of expert voices contesting supplement company claims with real data. “There needs to be a more robust response from the science community in the face of pseudoscience and misinformation,” says Tim Caulfield, a professor of health law at the University of Alberta, who has worked on studies and books examining ads and posts claiming to support the immune system on social media. He explains that supplement marketing often builds on the common misperception that if the right amount of a vitamin is good for you, more is better. "That's not the case at all," he says.

On the topic of supplement misinformation, Pieter Cohen, an associate professor of medicine at Harvard Medical School and a general internist at Cambridge Health Alliance, says, “The main problem is that the law permits companies to promote supplements as if they have important benefits for health even if there has never been a single study in humans to study the product's efficacy or safety.” 

Indeed, dietary supplements are not required to be reviewed by the FDA before they are distributed because they are not considered medications. Vitamins say right on the bottle that their claims “have not been reviewed by the FDA." Instead, they are predominantly regulated by the Federal Trade Commission, or FTC, which monitors the claims the labels make; however, this is limited to ensuring that the supplement makers are not explicitly claiming the product can be used as a treatment. The FTC does allow companies to suggest a range of benefits their products provide, which may be why up to 70 percent of adults in the United States take at least one dietary supplement daily, with the most common reason being to try to maintain or improve their health. 

While some individuals with specific vitamin deficiencies may benefit from these products (under a doctor's supervision), most of us do not. However, those marketed as "immune boosters" or "immune boosting" are more problematic. 

Despite suggestive labels, there is no way to "boost" the immune system. The immune system is a complicated and dynamic network of cells, proteins, hormones, and other biological components. Even if it were possible to ratchet up such a complex system, you wouldn't necessarily want to, because the immune system operates primarily by inducing inflammation. This alerts various immune cells to mobilize and fend off danger. In moderation, this is perfectly healthy, and the system has a braking mechanism all its own. But if a product were to truly “boost” the immune system, this mechanism would be amplified. We know what too much inflammation looks like: autoimmune disorders, inflammatory disease, and allergies. 

gummy vitamins spilling out of a bottle

Photo by Dan Dennis on Unsplash  

Ironically, in some cases, products heralded to improve immune function can actually suppress it. Take vitamin D, touted for its ability to enhance "immunity." While it may increase the inflammatory response, it has been shown to actually reduce the activity of other cell types—namely T cells, which are critical in forming long-term memory. The same is true of many other popular supplements, such as zinc, when a person takes substantially more than the recommended daily amount

Supplements can be actively harmful in other ways too. Since supplements aren't regulated by the FDA, they aren't evaluated for safety in the same way as pharmaceuticals. Of course, the manufacturers cannot knowingly use or include compounds that are known health hazards — legislation from 1994 dictates that ingredients used in supplement products must not have been shown to cause harm. But that doesn’t mean these products aren’t without yet unrecognized risks. 

“I think one of the biggest things that gets overlooked is the potential for a drug-drug interaction,” says Dr. Kathryn Nelson, a medicinal chemist at University of Minnesota. Physicians need patients to disclose what supplements they are using, including multivitamins, because they might interact with prescribed medications. From inactivating a pharmaceutical prescription, to dangerously exacerbating its effects, these products can have significant consequences. Yet many patients do not disclose or discuss their supplement use with their healthcare providers, due to their misguided perception that vitamins are safe or not worth mentioning. 

Additionally, the active ingredient in vitamins must be either be purified from a natural source or synthesized in a lab, and both methods have the potential for carry-over from compounds used in these methods. Such contamination is called “residual complexity,” Nelson says. This is particularly concerning when heavy metals are used and possibly present in the final product. In pharmaceutical drugs, these compounds would usually go to clinical trials, and any potential introductions of heavy metals removed in what’s called “process chemistry” to gain FDA approval. But the purification process of supplements are not reviewed by the FDA. This has opened the door for potential contaminants-heavy metals as well as other drugs and even pathogens-into these products.

Given all of this negative and even contradictory information about these products, why is the supplement market a multi-billion dollar industry? Much of the answer lies in its advertising. Companies often collaborate with social media influencers, who talk up how great the product is. And despite thousands of scientists across the country with expertise in nutrition and immunology, experts rarely publicly contradict these statements. 

Science communication is an important part in the scientific process. However, more often than not, important conversations happen only with other scientists at scientific conferences, or in journals behind paywalls. As a result, the larger non-expert community is left in the dark. Daniel Pham, the associate director of the Milken Institute's Center for Strategic Philanthropy, wrote an essay in 2016 which detailed the lack of support for science outreach by scientists, and an absence of communication training. Almost five years later, he says, “The same issues have resonated with me even more in the times of COVID. I feel like there’s a bigger sense of the need for improved communication of science to the public. But the tools we’re using are just woefully inadequate.”

The evidence of his statement can be seen in a recent study by Arizona State University, which showed the majority of scientists believe that it is important to inform and engage the general public about science topics. However, when asked about their personal interest or intentions of doing this, the answers are less enthusiastic. Often scientists are not encouraged or even rewarded for public outreach, which doesn't aid securing funding, publishing, or gaining tenure. One possible solution might be to reform the funding and promotion institutions so they reward researchers for this kind of public service.

However, scientists should also not anticipate their feedback will be immediately accepted based on their resumes. As Nelson points out, the first step in improving the public's access to verified information is building trust with experts. That includes breaking down the stigmas surrounding what it means to be a scientist, and making expertise more accessible. A recent example is the initiative Science on Tap, where a scientist describes their research in general terms to patrons at a local bar or venue. Pham has also started a similar effort at Johns Hopkins University, called Project Bridge, bringing small, introductory science demonstrations to public spaces such as farmer’s markets. Specific tactics to counter supplement marketers could also include partnering with influencers who are willing to share verified research, as well as lobbying for legislative reform. 

The supplement industry is a prime example of the dangers of misinformation, which is damaging to both science and the public at large. Cohen notes that the next steps are to urge the FDA and FTC to enforce existing laws prohibiting the promotion of products with disease claims, in an attempt to get them off the shelves. In the long-term, he notes the existing law on these products needs to be reformed so that "all products [are] registered with the FDA."

Scientists and researchers have the expertise to get information to the public and enact policy change. But it will require getting creative. “A lot of the misinformation really has become a social media story,” Tim Caulfield says, “so we need to go to where the misinformation resides." Scientists, he adds, "need to find their own voice.”

Peer Commentary

Feedback and follow-up from other members of our community

I really enjoyed this article! I’m not familiar with this field so it was really eye opening to learn about how many researchers struggle with an immensely profitable industry working against them. (I really wanted to share the info below, but I’m not sure if it’s fitting for a peer commentary since it’s a bit off topic.)

The field I’m more familiar with is exercise and weight loss research, but this field actually benefits from a bit of misinformation disseminated by celebrities, influencers, and advertisement. For instance, exercising has less of an effect on weight than limiting food intake. There are countless examples of this with a study showing that exercising has a plateauing effect on energy expenditure while simply eating earlier can influence one’s weight. But exercising and weight loss go hand in hand for most people (like in the TV series, The Biggest Loser). Yet researchers seem less reluctant to correct this since exercising has so many health benefits and many people are generally more motivated by outward appearance than health.

Shelby Bradford

This topic definitely feels like “looking behind the curtain” of these “miracles.”

Absolutely, this problem of “misinformation mills” challenging better science is a huge problem across several fields. And it is daunting for several reasons (what I listed and more) for experts to contest it, even though it is so needed. But coming up with strategies to get the real science to people, like I said, is just so imperative, and it is going to take a lot of creative solutions coming from a lot of angles.

My background is in pharmacy and I have had the opportunity to work in community pharmacies. You are absolutely right when you say that the supplement industry is a multibillion dollar industry. From my experience, pharmacies make lots of profit from the sale of supplements alone. Many pharmacists even prescribe them to patients to take with their medications though we have no scientific proof of their effectiveness and efficacy.

Recently, a family member underwent an orthopedic surgery and my dad, a nonscientist might I add, prescribed high strength vitamin c and calcium supplements which the family member started to take. At the next doctor’s appointment, the doctor advised to discontinue the supplements and use natural food sources to boost immunity and strengthen bones. My dad was quite surprised because his recommendation was based on one that was given to him by a doctor when he had orthopedic issues in the past.

What I am trying to say is, the use of supplements is also encouraged by health care providers who usually have no scientific evidence of efficacy but mere belief that these products work. The problem is sometimes belief is not enough. I totally agree that science communication plays a role in the scientific process but these conversations are not open to the public and I applaud you for breaking this down in a way that it is easy to understand and open to the public. 

Shelby Bradford

That's, I am certain, all too common. It’s sad, because often times, these suggestions are coming from places of good intentions. It came up several times in my interviews, these  ideas that “if something is good for you, more is better”. Another issue is the problem we have of anecdotes being taken as science truths, by the general public and, unfortunately as you point out, by healthcare providers as well. What’s more upsetting is that, for some people who do have deficiencies, because there aren’t good studies and of course no  substantial drug regulations, it’s hard to even prescribe a supplement that could help; it’s hard to establish how much to give, and of course there are huge inconsistencies with what’s on the label and what actually ends up in the bottle. For so many reasons, this industry needs more attention–to stop the misinformation (like immune “boosting  nonsense”) but also to get products that can offer real, reliable benefits to people who need them. 

I didn’t know that dietary supplements were responsible for so many emergency room visits, definitely concerning!

I think I agree that the heart of the issue is a disconnect between how supplements are regulated and how they are used and marketed. I’m also wondering if part of the issue could also be a lack of studies on the effects of the varied dietary supplements being taken, or is that  just an extension of the regulation issue?

Shelby Bradford

I think this example falls under the greater umbrella of the information we as consumers don’t actually have regarding supplements when they’re on market shelves, and all of that ties back to how they are not being regulated as drugs so the manufacturers don’t have to provide it, at least until a problem is detected through post-marketing monitoring. It’s likely that certain combinations or amounts of supplements contribute to some of the negative health outcomes; like I said in this article, we know that there are dangerous interactions that can occur with supplement use and prescription medications already. But I think  that ultimately, the issue of “lack of studies” on usage leading to negative health outcomes comes back to how supplements are regulated.