Key points to remember
- Experts say that many vitamin and mineral supplements offer no protective benefit against cancer or cardiovascular disease.
- Beta-carotene supplements may actually increase the risk of lung cancer in some people.
- Vitamin and mineral supplements can interact with certain medications and you should speak with a trusted health care provider before starting a supplement routine.
Vitamin and mineral supplements are unlikely to protect against cancer, cardiovascular disease or death, according to updated guidelines from the US Preventive Services. Task Force (USPSTF).
Although the use of dietary supplements is common among American adults, some experts say vitamins and supplements are a “waste of money”.
John Wong, MDprofessor of medicine at Tufts University and member of the USPSTF, told Verywell that it is reasonable to assume that certain anti-inflammatory supplements could reduce the risk of developing cancer or cardiovascular disease, but there is no is no evidence to support the association.
“It’s really basically a call for more research,” Wong said.
The USPSTF has issued a “D” rating for some supplements, including vitamin E and beta-carotene, to discourage people from using them.
Vitamin E supplements offer no protective benefit against cancer or cardiovascular disease, Wong explained. Beta-carotene supplements, which convert to vitamin A in the body, may even increase the risk of lung cancer in people who already have certain risk factors, such as smoking or occupational exposure to asbestos.
Wong pointed out that these recommendations were specifically made for non-pregnant adults. They do not apply to children, adults with chronic illnesses, people with nutritional deficiencies, or in circumstances where illnesses or medications interfere with nutrient absorption.
“A lot of it depends on your personal circumstances,” he said.
Misconceptions about vitamin and mineral supplements
The USPSTF made the same recommendation in 2014, which showed no evidence or support for taking multivitamins or mineral supplements. But Americans still spend billions of dollars each year on dietary supplements.
“People like something concrete when it comes to health. It is often easier to take a pill than to invest in behavior, diet and lifestyle change,” Melissa Majumdar, MS, RDregistered dietitian and bariatric coordinator at Emory Midtown University Hospital, Verywell told in an email.
Before taking any supplement, experts recommend considering misleading health claims on labels. The Food and Drug Administration does not endorse dietary supplements for supplement safety or effectiveness, or approve labeling before a supplement is offered for sale. Some supplement labels promote unproven claims that the product has “no side effects” or is “better” than a prescription drug.
Without evidence to support the effectiveness of supplements, many nutrition and public health experts say it’s best to focus on getting nutrients from your diet instead.
According Emma Laing, PhD, RDNclinical professor at the University of Georgia and national spokesperson for the Academy of Nutrition and Dietetics.
Laing told Verywell that the compounds in fruits and vegetables work “synergistically” to promote health and that they “cannot be duplicated in a dietary supplement.”
What about folic acid or vitamin D?
Despite insufficient evidence to support the use of supplements to reduce cardiovascular disease and cancer risk, the USPSTF recommends certain supplements. For example, folic acid, also known as vitamin B9, earned an “A” rating for use in pregnant women because it helps prevent certain birth defects.
“[They] should take folic acid 0.4 to 0.8 milligrams daily,” Wong said.
Although some foods are fortified with folic acid, it is still difficult to get enough of this vitamin from food alone.
Vitamin D is another nutrient that can be difficult to fully absorb through food. Your body generates vitamin D when your skin is exposed to the sun, but some people may have trouble absorbing enough vitamin D through sun exposure and foods like oily fish and beef liver.
“Vitamin D insufficiency is more common in people with darker skin, those who live in northern latitudes, and those who avoid sun exposure,” Laing said.
However, too much vitamin D can cause health problems, such as kidney stones, confusion, and vomiting. You can ask your health care provider to do a blood test if you are unsure if you need to take vitamin D supplements.
Vitamin D isn’t the only supplement that can cause harm in high doses. St. John’s wort, an herb that has been used to treat depression and lack of sleep, may interact with birth control and other medications, while vitamin C may make some cancer treatments less effective.
Even when supplements don’t cause harm, it may be pointless to take too much because they aren’t used by the body.
“More isn’t always better when it comes to the safety and effectiveness of dietary supplements,” Laing said.
What this means for you
Some supplements can interact with medications, making them less effective. Although supplements are available over-the-counter, you should consider speaking with a trusted healthcare provider before beginning any supplement regimen.