CNN

Most US adults and more than a third of children use dietary supplements, according to a new study from the US Centers for Disease Control and Prevention, and those numbers have held steady or increased.

Researchers from the CDC’s National Center for Health Statistics only looked at supplement use from 2017 through March 2020. Experts say use is likely even higher now because it increased during the Covid-19 pandemic. , especially before the advent of vaccines and treatments, studies and surveys have shown that people tried to boost their immunity in every way possible.

Around the world, the supplement market has been developing for at least a decade.

In the United States alone, it was an estimated market of $20.5 billion in 2021, according to Grand View Research, a market research and consulting firm.

The new study used information from the National Health and Nutrition Survey, a nationally representative set of surveys of the US population.

When asked about their supplement use in the past month, 58.5% of adults said they had taken at least one, and 34.8% of children and teens had taken one. That’s up from 57.6% of adults in 2017-18, although the number of children remained about the same.

The new research found some demographic consistencies: Women used more dietary supplements than men, and the more educated or wealthier a person was, the more likely they were to use a supplement.

White Asian and non-Hispanic adults used more supplements than black Hispanic and non-Hispanic adults. Supplement use also increased with age.

Multivitamins were popular: nearly a quarter of children took them and nearly a third of adults surveyed.

More than 18% of adults took vitamin D, the second most popular supplement.

Although the use of supplements remains popular with adults and children, science has not shown that they actually offer much health support.

In 2022, the U.S. Task Force on Preventive Services, an independent expert panel that creates health practice guidelines found “insufficient evidence” to recommend or against the use of vitamins A, C or E; multivitamins with folic acid; or combinations of antioxidants for the prevention of cancer or cardiovascular disease in a non-pregnant healthy adult.

Most studies show that multivitamins don’t actually make people healthier. A 2022 study in JAMA, which the task force relied on to develop its guidance, reviewed 84 studies involving nearly 700,000 people and found that multivitamin use had little or no benefit in prevention of cancer, heart and lung disease or death. They provided only a small benefit for the number of cancer cases, although the evidence is limited.

Other supplements may be harmful; the USPSTF said there was enough evidence in this study to advise against using beta-carotene supplements, which the body converts into vitamin A, to prevent cardiovascular disease or cancer because of a risk higher mortality, cardiovascular mortality and lung cancer.

“It is presented as a natural product. It’s billed as something different to what you’ll get from your doctor, and the idea is that there are no side effects because it’s all natural, and so it can only do good and not can never hurt. You can’t beat that,” said Dr. Paul Offit, a physician at Children’s Hospital of Philadelphia and author of “Do You Believe in Magic? Vitamins, supplements and all things natural: a look behind the curtain. »

Offit said some people might benefit from supplementing with vitamin D, which is considered good for bone health because it can help the body absorb calcium and phosphorus.

There are natural ways to get vitamin D through sun exposure, although people with darker skin tend to have lower levels in their system because the pigment melanin acts as a shadow. Older people also have a harder time absorbing vitamin D from the sun. Sunscreen can block it, as can windows.

People can get a good amount of vitamin D from foods like salmon and tuna and fortified drinks like orange juice and milk, but surveys show that many people’s intake falls short of the recommendation. minimum daily dose of 10 micrograms (mcg) for up to 1 year. , 15 mcg up to age 70 and 20 mcg for adults 71 and older.

Pregnant women should take a daily supplement of 0.4 to 0.8 milligrams (400 to 800 micrograms) of folic acid to prevent neural tube birth defects, according to a task force recommendation.

For those who choose to take a vitamin D supplement – or any supplement, for that matter – it’s important to note that they are only loosely regulated by the United States Food and Drug Administration and have no not have to meet the same strict standards as drugs.

With limited regulation, investigations over the years have found several supplements to be contaminated or not contain the same thing as stated on the label.

Experts say it’s a good rule of thumb Only purchase supplements that bear the USP or ConsumerLab label, which means the product has been tested by the independent non-profit United States Pharmacopeia Convention Dietary Supplement Verification Program or by ConsumerLab.com. A verified product guarantees that it is not contaminated with elements that could harm people, such as heavy metals or microbes, and guarantees that the product is what it claims to be.

Also, be sure to disclose that you take vitamins each time you see a doctor, and that you should disclose your medication intake.

“I think people don’t think of them as medicine. But some of them can interfere with therapies like medicine, including chemotherapy,” Offit said. “It’s really important that doctors know what you’re taking.”