Thousands of dietary supplement products are on the market today with claims to support, improve, or boost the immune system. Some claims are specifically targeted toward individuals who might be experiencing certain daily life stressors, such as more-than-usual physical or psychological stress. Others focus on the seasonal shift to wintertime when colds, coughs, and flu symptoms are commonly lurking.
“Support the body’s response to stress and fuel the immune system,” “primes the immune system to protect the body against daily stressors and environmental challenges,” “immune defense,” and “daily immune boost” are some common claims advertised on dietary supplement products marketed to support immune health. In other words, these claims are about resilience* to help your immune system face challenges to your health.
Operation Supplement Safety investigated dietary supplement products (through the lens of resilience) for immune health, their ingredients, and the strength of the evidence to support their claims.
What ingredients are frequently listed on immune supplement product labels?
Many immune health products list multiple ingredients on their labels. Some of the most common ingredients are plant-based: echinacea, elderberry, garlic, ginger, goji juice, goldenseal, holy basil, licorice, mangosteen, various mushrooms, noni, rose hip, slippery elm, and turmeric. However, the vitamins A, B, C, D, E, and K, and the minerals calcium, magnesium, selenium, and zinc are also common.
What is the evidence behind the claims?
Claims made for dietary supplement products and their ingredients to support or boost the immune system currently do not appear overall to have strong scientific evidence for or against their use by the otherwise healthy consumer looking to enhance their immunity. Research has been conducted on some ingredients, such as echinacea, elderberry, garlic, vitamin C, vitamin D, and zinc. Other ingredients do not yet seem to have the needed scientific evidence available to support their resilience claims.
According to the Food and Drug Administration and federal regulations for dietary supplements, claims made for dietary supplement products and their ingredients to “diagnose, treat, cure or prevent any disease” are not allowed. So, claims such as “natural flu prevention,” “boosts immunity and keeps you healthy from disease,” “resists infection” or any claim mentioning COVID are not permitted. Also, claims with words such as “protect,” “defend,” and “boost your immunity” are questionable. General claims with terms such as “supports” or “maintains” the immune system that are not specific to any prevention or treatment are otherwise permissible structure/function or health claims for dietary supplements.
What to look for in an immune supplement
In general, dietary supplements for immune health seem to be safe. However, evidence does exist that some products might be misbranded, which means that the ingredients listed on the label might not actually be contained in the product. Also, some products could contain substances not even reported on the labels. When choosing an immune health product:
- Look for products displaying third-party seals such as BSCG, Informed Sport, NSF Sport, or USP.
- Consider products that do not list multiple ingredients on the label.
- Steer away from products with quick-fix claims or statements that imply they can prevent or treat any disease or condition.
- For vitamins and minerals, make sure the amounts listed on the product label are below the upper limit and not much higher than the recommended daily allowances. See the Office of Dietary Supplements, National Institutes of Health information page about these recommendations.
*NIH defines "resilience" as "encompassing the capacity to resist, adapt to, recover, or grow from a challenge."
Updated 28 November 2022
