Do you need a multivitamin? What many people get wrong
Multivitamins have branched out. They’re now marketed for immune support, energy, menopause, hair/skin/nails, heart health, and more. Do you need a multivitamin? Here’s what they can—and can’t—do, according to the latest clinical trials...not the latest labels or ads. Scroll down to see a list of the best multivitamins, what’s wrong with most gummy vitamins, and which claims on multivitamin bottles are backed by weak evidence.
1. Multivitamins may curb the risk of cancer...slightly.
Taking vitamins or minerals has “little or no benefit in preventing cancer, cardiovascular disease, and death, with the exception of a small benefit for cancer incidence with multivitamin use,” concluded the U.S. Preventive Services Task Force in 2022.
Its bottom line: The evidence is “insufficient to recommend for or against the use of multivitamins.”
That leaves the decision up to doctors and patients, said the task force. Here’s what to consider.
“When the task force did a meta-analysis of four rigorous trials, those taking a multivitamin had a statistically significant 7 percent lower cancer risk than those who took a placebo,” says JoAnn Manson, chief of preventive medicine at Brigham and Women’s Hospital in Boston.
She co-led one of the four trials, the COcoa Supplement and Multivitamin Outcomes Study, or COSMOS.
The risk of lung cancer in multivitamin takers was 25 percent lower than in placebo takers when the task force combined the two trials that looked.
“COSMOS lasted only 3.6 years, which isn’t long enough to look at cancer,” notes Manson.
That—and the paucity of trials—played a role in the task force’s “insufficient” conclusion. And the 7 percent lower risk was modest. An estimated 200 people would have to take a multivitamin for several years to prevent one cancer.
But to Manson, there’s no downside and a potential upside.
“People with a strong family history of cancer or special risk factors for cancer, especially older adults, may want to consider a multivitamin as insurance,” she suggests.
“I rarely am a strong proponent of any supplement. We’ve tested them rigorously in multiple trials. And we often concluded that high doses do not confer benefits, as we did with the antioxidant vitamins C, E, and beta-carotene.”
“In some cases, they even have risks, such as the increased risk of hemorrhagic stroke with high doses of vitamin E in the Physicians’ Health Study II.”
And don’t expect a multivitamin to help treat cancer. “However, research suggests that multivitamins are safe and the benefits are likely to outweigh the risks,” says Manson.
2. Multivitamins may slow brain aging.
“It’s exciting that in three COSMOS trials, there was a signal for benefit for memory and cognitive aging with a multivitamin compared to placebo,” says Manson. (The trials were published after the Task Force report.)
“COSMOS-Mind did telephone-administered cognitive assessments, COSMOS-Web used online tests, and COSMOS-Clinic used gold standard, in-person assessments,” she explains.
“In a meta-analysis combining all three trials, which included more than 5,000 participants, there was a highly statistically significant benefit for both episodic memory and global cognition.”
(Global cognition includes both memory and executive function—that is, planning and organizing.)
“The difference in global cognition between groups was equivalent to slowing cognitive aging by about two years,” explains Manson.
“These are small changes, but they are meaningful because cognitive aging is progressive, and a multivitamin seems to slow it.”
That doesn’t mean that a multivitamin prevents dementia.
“You’d need to treat people for, say, five to 10 years to look at effects on dementia,” says Manson.
“But starting early to slow cognitive aging with a safe, affordable multivitamin is a reasonable strategy. It warrants further research.”
3. Multivitamins can’t fix an unhealthy diet.
“I do worry that people may think, ‘Oh, I’m popping this magic pill, so I don’t need to worry about diet,’” says Manson. “Supplements will never be a substitute for a healthy diet, along with not smoking and getting enough physical activity.”
“A healthy diet—with fruits, vegetables, whole grains, and fish—is the best way to get micronutrients and replace processed foods, red meat, and other unhealthy foods.”
That said, anyone over 50 needs a supplement or food with added vitamin B-12 because they may not make enough stomach acid to absorb the B-12 that occurs naturally in dairy, eggs, and meat, says the National Academy of Medicine.
And it’s easier to get enough vitamin D from a multivitamin than from a mix of fortified foods.
“A multivitamin shouldn’t be viewed as a panacea or magic bullet,” argues Manson. “But it’s safe, it may have benefits, and it costs only a few dollars a month.”
How to find the best multis
Here’s a selection of multivitamin-mineral supplements from major brands that meet our criteria (“What Your Multi Should Contain”).
Our minimums match the RDA or DV, when feasible. Our maximums are levels that are typically found in major brands and below amounts that may pose a risk. No gummies met our criteria. We didn’t disqualify multis with food dyes, given the low levels of dyes in a tablet or capsule and the lack of dye-free multis that met our criteria.
Don’t see your multi on the list? We didn’t look at every brand. You can check any label against our criteria.
Premenopausal women
(these multis have enough iron and folic acid)
- Centrum Adults
- Centrum Women
- Nature’s Bounty Daily Multi
- Target Up & Up for Women Under 50
- Walgreens Adults
- Walgreens Women’s
- Walmart Equate Complete Adults
Men and postmenopausal women
(multis that contain some iron are in bold)
- Centrum Minis Adults 50+
- Centrum Minis Men 50+
- Centrum Minis Women 50+
- Centrum Silver Adults 50+
- Centrum Silver Men 50+
- Centrum Silver Women 50+
- CVS One Daily Women’s 50+ Advanced
- CVS Women’s Daily 50+
- Target Up & Up Adults’ 50+
- Walgreens Adults 50+
- Walgreens Men’s 50+
- Walgreens Women’s 50+
- Walmart Equate Complete Adults 50+
- Walmart Equate Complete Women 50+
- Walmart Equate One Daily Men’s*
* Contains no food dyes. We found no dye-free Best Multi for premenopausal women, but Walmart Equate One Daily Women’s comes close (it falls short on vitamin E and has no magnesium).
— By Lindsay Moyer & Marlena Koch
Most gummy vitamins are missing key nutrients.
Want to sell more vitamins? Turn them into candy.
You can boast about your “no high fructose corn syrup” and instead add sugar or glucose syrup. And the “serving size” is typically 2 gummies, so customers will be back for more in half the time.
What’s more, many gummies have far less of the nutrients you’d get in an ordinary multi:
- Iron and iodine. Iron is missing. Iodine is scarce. Yet many premenopausal women get too little of both. And iron needs rise during pregnancy, but most “Prenatal” gummies have none.
- Other minerals. Many have little or no copper, magnesium, selenium, zinc, or chromium.
- Vitamins. A and C sometimes fall short, and K is often missing. Many “women’s” gummies from brands like Centrum, Olly, and VitaFusion have only 84 to 240 mcg of folic acid (140 to 400 mcg DFE). The CDC recommends that anyone who could become pregnant take 400 mcg a day of folic acid (680 mcg DFE) to prevent birth defects.
And ignore claims like “Energy,” “Beauty,” “Immune,” “Metabolism,” or “High Potency.” It’s all marketing malarkey that has nothing to do with what works.
Can’t swallow large pills? Try Centrum Minis 50+.
Most "support" claims are backed by weak evidence.
Supplements can claim to “support” nearly anything as long as they don’t mention a disease. But many claims are backed by weak evidence. These examples from One A Day Women’s and Women’s 50+ are typical of many vitamin claims.
(Note: None of the studies below tested One A Day.)
Eye health “with Vitamins A, C, E & Zinc”
High doses of those nutrients can slow macular degeneration, but only if you already have an intermediate or advanced case. The same high doses had no impact on cataracts.
Healthy energy metabolism “with B vitamins”
Don’t expect B vitamins to make you more energetic or speed up your metabolism.
Heart health “with Folic Acid, Vitamins B6 & B12”
In large clinical trials, high-dose B vitamins didn’t reduce the risk of heart attacks.
Healthy brain function “with B vitamins”
It’s worth taking a multi to get the Daily Value for vitamin B-12 because a deficiency can masquerade as dementia. Taking extra B-12 or other B vitamins doesn’t help keep you sharp. A multi may help, though.
Healthy muscle function “with Vitamin D”
Vitamin D didn’t strengthen muscles or physical performance in clinical trials.
Skin health “with Vitamins A, C, E, Zinc & Copper”
There’s no good evidence that a multi will help your skin (or hair).
Immune health “with Vitamins A, C, D, E, Selenium & Zinc”
In clinical trials on a total of roughly 2,220 people, multivitamin takers were just as likely to get sick—or stay sick for just as long—as placebo takers.
Bone health “with Calcium & Vitamin D”
It’s worth taking a multi to get the Daily Value for vitamin D. But most multivitamins have only 0 to 25 percent of the DV for calcium.
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