Drawn by the lure of multivitamins and dietary supplements filling the nutritional gaps in their diets, Americans in 2021 spent nearly $50 billion on vitamins and dietary supplements.
But Northwestern Medicine scientists say that for non-pregnant, otherwise healthy American women, vitamins are a waste of money because there isn’t enough evidence they help prevent cardiovascular disease or cancer.
“Patients ask all the time, ‘What supplements should I take?’ They waste money and get carried away thinking there must be some magic set of pills that will keep them healthy when we should all be following the evidence-based practices of healthy eating and exercising said Dr. Jeffrey Linder, chief of general internal medicine in the Department of Medicine at Northwestern University Feinberg School of Medicine.
Linder and fellow scientists at Northwestern Medicine have written an op-ed that will be published June 21 in JAMA which supports new recommendations from the United States Preventive Services Task Force (USPSTF), an independent group of national experts that frequently makes evidence-based recommendations for clinical preventive services.
Based on a systematic review of 84 studies, the new USPSTF guidelines say there was “insufficient evidence” that taking multivitamins, paired supplements, or single supplements can help prevent cardiovascular disease and cancer in otherwise healthy non-pregnant adults.
“The task force doesn’t say ‘don’t take multivitamins,’ but there’s this idea that if they were really good for you, we would know by now,” Linder said.
The task force specifically recommends against taking beta-carotene supplements due to an increased risk of lung cancer, and recommends against taking vitamin E supplements because it has no clear benefit in reducing mortality, cardiovascular disease or cancer.
“The harm is that talking to patients about supplements during the very limited time we have to see them misses guidance on how to really reduce cardiovascular risk, such as through exercise or quitting smoking,” said Linder said.
More than half of Americans take vitamins. Why?
More than half of American adults take dietary supplements, and supplement use is expected to increase, Linder and colleagues wrote in the JAMA editorial.
Fruit and vegetable consumption is associated with decreased cardiovascular disease and cancer risk, they said. So it’s reasonable to think that essential vitamins and minerals could be extracted from fruits and vegetables, packaged into a pill, and save people the trouble and expense of maintaining a balanced diet. But, they explain, whole fruits and vegetables contain a mix of vitamins, phytochemicals, fiber and other nutrients that likely work synergistically to provide health benefits. Isolated micronutrients may act differently in the body than when naturally packaged with a host of other food components.
Linder noted that people with vitamin deficiency can still benefit from taking dietary supplements, such as calcium and vitamin D, which have been shown to prevent fractures and possibly falls in old people.
The new guidelines do not apply to pregnant women
The new USPSTF guidelines do not apply to people who are pregnant or trying to get pregnant, said JAMA editorial co-author Dr. Natalie Cameron, a general internal medicine instructor at Feinberg.
“Pregnant women should keep in mind that these guidelines do not apply to them,” said Cameron, who is also a physician with Northwestern Medicine. “Certain vitamins, such as folic acid, are essential for pregnant women to support healthy fetal development. The most common way to meet these needs is to take a prenatal vitamin. More data is needed to understand how supplementation with specific vitamins may alter the risk of adverse pregnancy outcomes and cardiovascular complications during pregnancy.”
Additionally, recent research from Northwestern found that most women in the United States had poor heart health before becoming pregnant. Cameron said that in addition to discussing vitamin supplementation, working with patients to optimize cardiovascular health before pregnancy is an important part of prenatal care.
Eating healthy, exercising is ‘easier said than done’
Dr Jenny Jia, co-author of the JAMA editorial which studies chronic disease prevention in low-income families through lifestyle interventions, said healthy eating can be a challenge when America’s industrialized food system fails to prioritize health.
“Eating a healthy diet and getting more exercise is easier said than done, especially among low-income Americans,” said Jia, a general internal medicine instructor at Feinberg and a physician at Northwestern Medicine. . “Healthy eating is expensive, and people can’t always afford to find environments to exercise – maybe it’s dangerous outside or they can’t afford it. to afford a facility. So what can we do to try to make it easier and help support healthier decisions?”
Over the past few years, Jia has worked with charity pantries and banks that provide free groceries to people in need to try to help customers choose healthier choices at pantries. and to educate those who donate to provide healthier options or money.