Dietary supplements are wildly popular, but large clinical trials and other research by Fred Hutch Cancer Center scientists show that many common dietary supplements offer little proven benefit for cancer prevention, and in some cases may even increase cancer risk.
“It would be nice if we had a pill that we could take that could protect us from disease,” said Garnet Anderson, PhD, director of Fred Hutch’s Public Health Sciences Division (PHS) and holder of the Fred Hutch 40th Anniversary Endowed Chair. “But it’s not that easy.”
Initially created to treat nutritional deficiencies, dietary supplements are now sold as a panacea for nearly all ills ― including cancer ― and unlike drugs used to treat disease, they face few regulatory hurdles. There’s no rigorous vetting process to get U.S. Food and Drug Administration (FDA) approval; supplements have no FDA approval process. The FDA only gets involved if they’re shown to be unsafe, misbranded or adulterated once they’re on the market.
Yet in 2025 alone, U.S. consumers spent an estimated $60 billion (or more) on dietary and over-the-counter supplements, their popularity fueled by an aging population and a burgeoning wellness industry replete with charismatic online influencers.
Who wouldn’t want to simply take a “magic pill” to boost a flagging immune system, sharpen a foggy mind and/or protect them from ― or even eliminate ― cancer?
Unfortunately, it’s not that simple. That’s why in addition to researching and developing cures for cancer, Fred Hutch scientists have drilled down into a slew of supplements to see whether they offer any protection against disease. Their data point to a consistent theme: supplements have not been shown to prevent cancer and, in some cases, may actually increase cancer risk.
What’s more, some supplements can interfere with cancer treatments, something not all patients realize. Many people assume they’re harmless, even beneficial, and don’t think to tell their doctors.
Curious about the benefits (and potential harms) of dietary and other over-the-counter supplements? Read on for their findings:
