The Allure of Immune-Boosting Supplements: Separating Fact from Fiction

The Rise of Immune-Boosting Supplements

Walking down the supplement aisle, it’s hard not to be drawn in by the bottles of pills, gummies, and powders that promise to supercharge your immune system. You’re not alone if you’ve ever popped a vitamin C tablet hoping to avoid the sniffles or recovering faster from a cold. Millions of Americans turn to dietary supplements with the hope of boosting their immunity. A recent study published in JAMA Network Open highlights just how widespread this trend has become. The study, which included more than 15,000 participants, found that roughly one in nine U.S. residents used immune-boosting supplements between January 2017 and March 2020. This phenomenon speaks to a broader cultural desire to optimize health and take control of our well-being, especially in the wake of the COVID-19 pandemic. As Dr. Michael Ben-Aderet, an associate medical director at Cedars-Sinai in Los Angeles, puts it, “There’s really this sense of people trying to optimize their health.”

However, what’s striking is how many people turn to these supplements without a doctor’s recommendation. While the idea of giving your immune system a little extra support might seem harmless—or even proactive—the question remains: Do these supplements actually work? According to infectious disease experts, researchers, and supplement safety advocates, the evidence is far from convincing.

What Do Immune-Boosting Supplements Promise?

Immune-boosting supplements often claim to provide the vitamins, minerals, and botanicals your body needs to fight off germs and recover faster from illness. At first glance, this makes sense. Certain nutrients, like vitamins A, C, and D, and minerals like zinc, play a crucial role in supporting immune function. Dr. Mahtab Jafari, a professor of pharmaceutical sciences at the University of California, Irvine, explains that these nutrients are essential for protecting against pathogens. Deficiencies in them can leave you more vulnerable to getting sick.

However, the reality is that most Americans already get adequate amounts of these nutrients through a balanced diet. For people who aren’t deficient, taking extra supplements may not offer any additional benefits. Despite this, the market is flooded with products containing these nutrients, often alongside a mix of other ingredients like elderberry, echinacea, and other botanicals. But for these substances, the evidence is even thinner. As Dr. Jen Wall Forrester, a senior medical director at UC Health in Cincinnati, notes, “I wish there was a magic bullet,” but immunity is a complex process that no single supplement is likely to revolutionize.

The Science Behind Immune-Boosting Claims

While vitamins and minerals like vitamin D, vitamin C, and zinc are some of the most studied ingredients in immune supplements, the results are far from conclusive. For example, studies on vitamin D have yielded mixed results. A 2020 review found that vitamin D supplements didn’t protect against viral infections in people with normal or high levels of the nutrient. Yet, a larger 2021 review of nearly 50,000 participants suggested that vitamin D supplements might slightly reduce the risk of acute respiratory infections. However, this study has been criticized for potential conflicts of interest, as some of the authors had ties to supplement companies.

The story isn’t much different for vitamin C and zinc. A 2013 review of over 11,000 participants found that vitamin C supplements didn’t reduce the risk of catching a cold in the general population, though they might shorten the duration of symptoms. Similarly, a 2024 review of zinc supplements involving more than 8,000 people found that they did little to prevent colds, though they might help reduce how long the illness lasted. Botanicals like elderberry and echinacea, which are commonly found in immune supplements, have even less reliable research backing their effectiveness.

Why the Evidence is So Murky

One of the biggest challenges in determining whether immune-boosting supplements work is the lack of high-quality research. Randomized clinical trials—the gold standard of medical research—are rare for these products. Dr. Pieter Cohen, an associate professor at Harvard Medical School who studies dietary supplement safety, points out that the supplement industry operates in a regulatory gray area.Unlike prescription drugs, dietary supplements don’t require FDA approval before hitting the market. This means companies can sell products without rigorous testing to back up their claims. Furthermore, supplements aren’t required to prove to the FDA that they contain what they claim or that they’re safe.

The consequences of this lax regulation were highlighted in a 2022 study that analyzed 30 supplements marketed for immune support. More than half of the products had inaccurate labels, 13 were misbranded, and nine contained ingredients that weren’t listed on the label. This lack of oversight creates a situation where consumers may not even know what they’re putting in their bodies, let alone whether it’s effective.

The Bottom Line: Should You Try Immune-Boosting Supplements?

So, what’s the verdict? While immune-boosting supplements might seem like a harmless way to support your health, the evidence suggests that they’re unlikely to deliver on their promises for most people. Dr. Ben-Aderet advises consumers to approach these products with a “healthy dose of skepticism.” If you’re still considering trying them, there are a few steps you can take to make an informed decision. First, look for products that have been tested by third-party organizations like U.S. Pharmacopeia or NSF International, which verify the quality and accuracy of supplement labels. You should also check the FDA’s website to see if the company has faced any warnings for misleading claims or poor manufacturing practices.

Most importantly, talk to a healthcare provider before adding any new supplement to your routine. They can test for nutrient deficiencies, warn you about potential side effects or unsafe dosages, and check for dangerous interactions with any medications you’re already taking. And if your doctor gives you the green light, Dr. Wall Forrester says, “You could just try it out”—but be prepared for the possibility that you might be wasting your money. At the end of the day, no supplement can replace a balanced diet, regular exercise, and good health habits when it comes to building and maintaining a strong immune system.