How many of you are taking a multivitamin? If you’re in the USA, over 50% of adults are taking one. I’ve also taken it sometimes, off and on. I wouldn’t feel any different (good or bad) and then I’d stop for a while, and then some flashy new organic-ish version would be on sale at Costco — and away we go again. But did you know that the reason you might be taking it doesn’t have any evidence for it?
For me, I would want it to be shown that it makes you live longer or prevents cancers and heart attacks, the major killers in our world. Did you know there’s strong evidence that a daily multivitamin doesn’t do any of that?
Many take an MVI because they think they’re deficient in a vitamin; it’s actually very rare in almost every developed country to be deficient in any micronutrient you’d find in a multivitamin, except vitamin D as the usual outlier. But apart from some exceptions, the vast majority of us are not replacing any deficiency by taking a pill.
So, let’s cut through the social media influencer fog and review the facts, the hardcore data. To start with, in 2013 there was a meta-analysis of randomized control trials, covering over 90,000 people, and it showed no benefit or harm in deaths and mortality, including from cardiac disease.
I feel it’s very impressive data, since randomized controlled trials are the best studies (able to prove cause and effect).
More recently, the US Preventive Services Task Force updated their previous review in 2022, and they concluded again “insufficient evidence” to taking a daily multivitamin:
One of the shortcomings for me about this USPSTF review is that the timeframe of data collection was only 4 years long, and it’s hard to prove mortality in a four-year timeline. The better studies to show long-term effects are prospective cohort studies. And we are fortunate with a brand-new meta-analysis of 3 cohort studies that just came out earlier this year. It reviewed four hundred thousand patients from different studies over 27 years, so it’s an impressive amount of time to see if there’s a change. And again, like the other studies, it showed non-significant change in mortality:
They Can Harm You…
I’m a big fan of the risk/benefit ratio, and so far, we’ve concluded that there’s strong evidence that there are no meaningful benefits in taking a multivitamin every day. What about the harms? The good news is that these studies all show no major harms in taking a multivitamin long-term (apart from the harms in separately taking vitamin E or beta carotene). But I would argue that there is a general harm! I’m convinced that our modern world’s obsession with multivitamins — and most supplements — is a major distraction from making meaningful lifestyle changes in food choices that can literally improve your life.
For example, I can almost guarantee that an overwhelming amount of my readers are not taking enough of the macronutrient that an estimated 90 percent of us are deficient in: fiber!
Yes, it’s very un-sexy and zero-trending fiber, available only from plants and no meat products, that has massive evidence from the best studies (interventional trials) to give you what you are expecting from your expensive Himalayan-anointed regenerative MVI elixir: longer life with less heart disease and less cancers. It’s fantastic and yet so massively under-appreciated that it’s really shocking to me, we’re so shackled by our social media and cultural blinders. We watch hours of influencers hyping up their favorite supplements and researching comments on Amazon, but we skip the boring YouTube shorts promoting plant-based whole foods. So cringe, bruh.
Don’t believe me about fiber? One more data point: we have another brand new, 2024 meta analysis of cohort studies with over three million people showing the following:
Results: …higher consumption of total dietary fiber significantly decreased the risk of all-cause mortality, CVD-related mortality, and cancer-related mortality by 23, 26 and 22 % (HR:0.77; 95%CI (0.73,0.82), HR:0.74; 95%CI (0.71,0.77) and HR:0.78; 95%CI (0.68,0.87)), respectively. The consumption of insoluble fiber tended to be more effective than soluble fiber intake in reducing the risk of total mortality and mortality due to CVD and cancer. Additionally, dietary fiber from whole grains, cereals, and vegetables was associated with a reduced risk of all-cause mortality, while dietary fiber from nuts and seeds reduced the risk of CVD-related death by 43 % (HR:0.57; 95 % CI (0.38,0.77)).
Conclusion: This comprehensive meta-analysis provides additional evidence supporting the protective association between fiber intake and all-cause and cause-specific mortality rates.
Did you see that last line? “Dietary fiber from nuts and seeds reduced the risk of CVD-related death by 43%”. That’s extraordinary! That 43% magnitude of improvement would be front-page news if that were part of some big drug company trials, and yet here we are. It’s so damn hard to break through the current.
And yet here I stand (or sit and stand with my adjustable desk) with my little blog, doing my best to share the news, and I shall continue to fight the good fight. I wrote about this issue years ago, and I’m sure I’ll cover it again.
So, what do you think? Assuming half of you are taking a multivitamin, have I changed your mind? Feel free to leave comments below.
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I would submit that the tendency to take multivitamins is likely due to a desire to do something easy and “healthy” for oneself driven by the personal realization that eating right and exercise is never going to happen. It’s a classic panacea.
I agree with the general idea that humans are hard-wired to feel that a pill can solve your problems. I see it with the statins, I have hundreds of patients on a statin to lower cholesterol and there’s a slight chance they’ll actually eat worse than usual. It’s called the “licensing effect”