Do You Really Need A Multivitamin?
I’m a multivitamin skeptic who has reported on women’s health for more than two decades, but even I occasionally fall prey to a buzzy headline. Most recently, an article about the relationship between multivitamins and cognitive health sent me straight to the supplements aisle. But before I spent $20 on something I wasn’t sure I needed, I decided to ask a few experts for their advice. Here’s what they told me.
Spoiler: You probably don’t need a multivitamin
The idea of multivitamins as “nutritional insurance” has been around since the first multis hit shelves nearly a century ago, says Jonathan Jarry, a science communicator at the Office for Science and Society at Montreal’s McGill University. “We’re still buying into that marketing,” says Jarry, whose work involves making scientific research more accessible to the general public. “The vast majority of people do not need multivitamins.”
While getting enough nutrients through diet is the ultimate goal, there are a few circumstances in which a multi makes sense, says Jamila Kanji, a Vancouver-based registered dietitian and Menopause Society-certified practitioner. “People who have digestive disorders—such as Crohn’s—and have issues absorbing certain vitamins and minerals could benefit from a multivitamin.” As could someone who follows a restrictive diet, which is common among midlife women. (This would be a temporary measure as they work up to eating a wider variety of foods.)
What’s the latest research?
The article that sent me to the supplements aisle references findings from the COSMOS-Mind three-year trial, part of the Cocoa Supplement and Multivitamin Ongoing Study, conducted at Brigham and Young Women’s Hospital in Boston and the Fred Hutchinson Cancer Research Center in Seattle. After three years of daily multivitamin use, subjects—whose average age was 71—experienced improved overall cognition, episodic memory and executive function. Sounds great, but Jarry notes that these were “tiny improvements due to statistical noise.”
“Can we really extrapolate from this data that healthy midlife women should take multivitamins?” asks Kanji. “I don’t think so.” In terms of cognitive health, she recommends the MIND diet, which focuses on leafy greens, berries, whole grains, nuts and legumes.
There just isn’t any major scientific proof that multivitamins have significant benefits for the average person, seconds Jarry. “Instead, it’s the same boring stuff that will keep you healthy as you age: getting enough sleep, eating well, building muscle, keeping your brain active.”
How can I tell if I have a nutritional deficiency?
Kanji recommends midlife women ask their doctors to have their iron, B12 and vitamin D levels analyzed in their routine bloodwork—and then bring these results to a registered dietitian for insight on how to improve any deficiencies either through diet or supplementation.
The final word on multivitamins
“If you’re not eating a varied diet and you want to take a multivitamin, make sure [it contains] enough of the key nutrients,” says Kanji—including iron (menstruating women need 18 mg daily), vitamin B12 (2.4 mcg) and vitamin D (consult your doctor for your ideal dosage). “Otherwise, taking the nutrient as its own supplement is probably going to benefit you more.”
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Maureen Halushak is the editor-in-chief of Chatelaine. Outside of work she's an avid runner, writer, reader and dog walker.
