Do supplements really prevent diseases? Experts say they “provide minimal to no benefit” for most healthy people

By Alexa MikhailSenior Reporter, Fortune Well
Alexa MikhailSenior Reporter, Fortune Well

Alexa Mikhail is a former senior health and wellness reporter for Fortune Well, covering longevity, aging, caregiving, workplace wellness, and mental health.

Closeup of an African American woman standing in her bathroom in the morning taking a vitamin with a glass of water.
New guidelines highlight multivitamins are not sufficient in reducing cancer and heart disease.
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As the dietary supplement industry continues to boom, the United States Preventive Services Task Force (USPSTF) announced that “the evidence is insufficient” to support the use of supplements to help prevent cardiovascular disease and cancer in healthy, non-pregnant adults. 

More than half of all Americans over 20 take some sort of vitamin supplement, with roughly 80% of women over 60 reporting taking them, according to data from the National Health and Nutrition Examination Survey. The North American dietary supplement market was worth over $50 million in 2020 and is expected to increase by 5.6% between 2021 and 2028, according to Grand View Research

But the independent panel of scientists on the task force, who analyzed 84 studies on multivitamins, single vitamins and minerals and a combination of vitamin and mineral supplements to prevent the risk of cardiovascular disease and cancer, recommended against them for most healthy people. They further advised against taking beta-carotene due to a possible increased risk of lung cancer and cardiovascular mortality, as well as Vitamin E due to lack of evidence for a “net benefit” in reducing certain cardiovascular diseases, cancer and mortality for healthy individuals. 

“Vitamin supplements are not necessarily a silver bullet for healthy Americans,” said Dr. Jenny Jia, an instructor of general internal medicine at Northwestern University Feinberg School of Medicine who contributed to an editorial in support of the recommendation. “The study is showing that they really provide minimal to no benefit when it comes to preventing the common chronic diseases that burden Americans, including heart disease and cancer.” 

The Northwestern scientists who wrote the article hope this halts peoples’ gravitation toward certain supplements and compels them to invest in their health in a myriad of other ways. 

“Patients ask all the time, ‘What supplements should I be taking?’ They’re wasting money and focus thinking there has to be a magic set of pills that will keep them healthy when we should all be following the evidence-based practices of eating healthy and exercising,” said Dr. Jeffrey Linder, chief of general internal medicine in the department of medicine at Northwestern University Feinberg School of Medicine, in a press release Tuesday

“One of the reasons why dietary supplements may be popular is that there’s a general perception that they’re all benign, may be naturally derived, which may or may not be true,” Jia says. “We don’t have a good understanding of what are the risks of taking vitamin and mineral supplements … because we don’t have that data doesn’t mean that they’re necessarily just benign.” 

Northwestern scientists highlight that while various supplements may have “antioxidative and anti-inflammatory effects,” the extraction of certain elements in the form of pills act differently than fruits and vegetables, for example, which contain many other nutrients working in tandem.

“Taking a chemical formulation of a vitamin is not necessarily the same thing as taking the vitamin when incorporated into food,” said Dr. Frank A. Smith, medical director of intensive cardiac rehabilitation at Trinity Health St. Joseph Mercy. “There’s a lot we don’t understand …[the vitamin] may be metabolized differently or absorbed differently when it’s bound to a whole food, than when it’s in a powder that just basically dissolves in your stomach.” 

Instead of spending money and time on supplements, Northwestern scientists suggest “lower-risk, higher-benefit activities,” such as following a healthy diet, exercising, maintaining a healthy weight and avoiding smoking. 

“When it comes to living long, healthy lives, we’re finding that, thus far, packaging what we think are the most healthy components of fruits and vegetables into a pill, it’s unfortunately not a sufficient shortcut to adopting the healthy behaviors,” Jia says.

Supplements may work for some people, specifically those who have vitamin deficiencies. Jia recommends those individuals work with their doctor to suggest a plan forward. And certain supplements, including folic acid and iron, are recommended to those who are or may soon be pregnant. 

There is a craze for generally healthy individuals to find further ways to maintain and better their wellbeing, which Jia and Smith say is a good thing but has limitations. The bottom line is prioritizing other healthy choices like maintaining a balanced diet. 

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