Yet the conclusion remained the same as that of 2014: If you are a healthy, nonpregnant adult, there is “insufficient evidence” of any benefits to extending one’s life in taking vitamin E, vitamin D, calcium, vitamin A, beta carotene, vitamin B3, vitamin B6, vitamin C and selenium.
However, there is enough evidence to recommend against the use of beta carotene supplements, which the body turns into vitamin A, to prevent cardiovascular disease or cancer “because of a possible increased risk of mortality, cardiovascular mortality, and lung cancer,” the task force said.
Nor should people take vitamin E “because it probably has no net benefit in reducing mortality, cardiovascular disease, or cancer,” the task force said.
Another evidence-based intervention: the DASH diet, which stands for “dietary approaches to stop hypertension.” The diet successfully reduces high blood pressure, studies have shown. Both the Mediterranean and DASH diets avoid processed foods and focus on fruits, vegetables, beans, lentils, whole grains, nuts and seeds.
“Rather than focusing money, time, and attention on supplements, it would be better to emphasize lower-risk, higher-benefit activities … following a healthy diet, getting exercise, maintaining a healthy weight, and avoiding smoking,” Linder and his colleagues wrote.
Billions of dollars
Yet despite the consistent message from the scientific community, “more than half of American adults take dietary supplements,” spending an estimated $50 billion in 2021, according to Linder and his colleagues.
Why would we spend so much money on pills with so little evidence to support their benefits?
Then, once people see vitamins as being “good and healthy,” another behavior called “dose insensitivity” takes hold: If a little is good, more must be better, said Ubel, who is professor of business, public policy and medicine at Duke University’s Fuqua School of Business in Durham, North Carolina. Add to that human bias toward anything labeled “natural” or “botanical” and the likelihood of purchasing vitamins and minerals marketed in that manner rises, he said.
“Advertising agencies recognize this bias,” Ubel added. “Now, people can make up for the lack of fruits and veggies in their diets by ingesting daily supplements.”
CNN reached out to the Council for Responsible Nutrition, a trade organization for the supplement industry, and received this response:
“The apparent limited evidence should not be misinterpreted as the absence of evidence,” said Andrea Wong, senior vice president for scientific and regulatory affairs for the council. “Numerous research studies support the use of multivitamins by most Americans for a range of benefits.”
Some populations need supplements
People with limited access to healthy food choices or who have certain medical conditions or anyone over the age of 65 may need to focus on adding specific micronutrients to their diet, experts say.