Half a dozen doctors and scientists pointed out that there are no supplements that have been shown to extend human life span in a large clinical trial. Photon / 123rf
Many anti-ageing influencers say yes. Here’s what doctors and scientists think.
It seems like every longevity influencer has a supplement (or several) they swear by.
Bryan Johnson, the founder of the “Don’t Die” movement, takes fistfuls of pills throughout the day, many of which he now sells. Gary Brecka, the host of The Ultimate Human podcast, promotes powders, tablets, beverages, nasal sprays, skin patches and even injectables on his website. And countless Instagram and TikTok personalities will assure you that they’ve never felt or looked better, thanks to their favourite supplements (which they’re often paid to promote).
Are any of these magic beans legitimate?
Half a dozen doctors and scientists interviewed for this article pointed out that there are no supplements that have been shown to extend human lifespan in a large clinical trial. As a result, some said that the evidence supporting supplements for longevity was too weak, and the industry too unregulated, to endorse people spending their money on them.
“That whole gemish of things that are hawked and being promoted by influencers and longevity so-called experts or whatever, there’s just no data,” said Dr Eric Topol, founder of the Scripps Research Translational Institute and author of Super Agers.
Others, however, are optimistic about the potential for supplements to improve healthspan – how long a person lives without serious disease – and said that the pills and powders can have a place in supporting people’s health as they get older.
“I look at the whole space as one of opportunity,” said Dr Eric Verdin, the president and CEO of the Buck Institute for Research on Ageing. “But one also that’s fraught with dangers for consumers and false promise.”
Supplements promoted for healthy ageing generally fall into two camps: traditional vitamins and more experimental products. Here’s a look at each.
Several of the experts said that vitamin D, vitamin B12 and omega-3s are the three nutrients they tend to recommend for older adults. That’s in large part because it’s not unusual for people to be deficient in them, particularly as they age. Older adults can have difficulty absorbing vitamin B12, and certain medications can exacerbate the problem. People who live in places without much sunshine may not receive enough vitamin D, and those who don’t eat fish regularly may not be getting enough omega-3s.
Observational studies have suggested that having low levels of vitamin D and omega-3s, in particular, seems to raise the risk for several health conditions related to ageing, such as heart disease, cancer and osteoporosis. Those findings have spurred research to see if supplementing with the nutrients could help prevent those diseases. However, the results from clinical trials have largely been lacklustre.
In two of the most high-profile studies, the 2018 VITAL trial conducted in the United States and the 2020 DO-HEALTH trial conducted in Europe, thousands of older adults took a vitamin D or omega-3 supplement (or both) for three to five years. When looking at the participants as a whole, neither study showed the supplements had any benefit when it came to cancer diagnoses, cardiovascular health, bone fractures or cognition.
The results were a little more promising for the subset of participants who may have had a deficiency in omega-3s. Specifically, people who ate fewer than 1.5 servings of fish per week did see a reduction in strokes and heart attacks from taking a supplement. There was no difference in the results for people who entered the trials with lower levels of vitamin D.
Consistent with these findings, many clinicians take a nuanced approach when counselling patients about vitamin supplements. Alison Moore, the director of the Stein Institute for Research on Ageing and the Centre for Healthy Ageing at the University of California San Diego, says that she will occasionally recommend omega-3s, vitamin D and B12 to her patients if she has reason to believe they have a deficiency. But, she added, “if they have a healthy diet, then I really don’t recommend supplements”.
Recently published follow-up analyses from the VITAL and DO-HEALTH trials have added a new layer of intrigue around the supplements, suggesting they may potentially impact aspects of the ageing process itself. Vitamin D was associated with slower telomere shortening, and omega-3s were tied to slower biological ageing.
Dr JoAnn Manson, a professor of medicine at Harvard Medical School who led the VITAL trial, speculated that these effects might stem from the supplements’ anti-inflammatory properties. But, she added, it’s “really unclear” how exactly that translates to a longer lifespan.
The experimental – and more buzzy – category of longevity supplements includes things like nicotinamide adenine dinucleotide (NAD+), spermidine and urolithin A. Some researchers think they have the potential to improve health span and counteract the declines in organ and muscle function that occur with age.
Many of these are molecules that the body already makes for cellular health, and in theory, they may have anti-ageing benefits if their quantities are increased through supplementation. For example, NAD+ plays an essential role in cellular energy production, and its levels fall with age. Spermidine appears to stimulate autophagy, one way that the body recycles damaged proteins and cell parts; autophagy also declines with age. Urolithin A is produced by gut bacteria and is thought to improve the health of mitochondria – the power plant of the cell.
Testing on rodents and worms, or on human cells in a dish, has shown that these molecules can improve some of the negative effects of ageing and even prolong lifespan. Supplement companies often cite these studies on their websites, and influencers tend to repeat them as evidence that the products work.
Topol called such claims “smoke and mirrors”. There’s a big jump between improving the health of a mouse or helping a worm live longer and showing the same benefit in a person. Indeed, the few small human clinical studies that do exist for these supplements found minimal, if any, improvements in health.
Some previously trendy anti-ageing supplements have fallen out of favour after the findings in humans didn’t live up to the results in animals. For example, preliminary studies on resveratrol generated a lot of excitement. But subsequent ones found no tangible health benefits, so geroscientists have largely abandoned their research into it.
The lack of long-term clinical trials also means that there are open questions around the safety of these supplements. Some may be okay in small doses or when taken for short periods of time, but there could be unanticipated side effects over many months or years.
And as with virtually all supplements, what is on the bottle’s label might not match what’s inside the pill. One recent study testing NMN (nicotinamide mononucleotide, a molecule related to NAD+) and urolithin A supplements found that the majority contained a different amount than what the label claimed, in some instances by as much as 100%. These issues were found across all brands and at all price points, said Dr Andrea Maier, a professor of medicine, healthy ageing and dementia research at the National University of Singapore, who led the study.
For those interested in trying these types of anti-ageing supplements, the experts urged caution but stopped short of telling people to completely steer clear of them. Verdin, who co-founded one supplement company and is an adviser to another, recommended working with a physician who is familiar with the products and will monitor you for side effects.
Longevity supplements could harm your wallet more than anything, Moore said. But she questioned whether taking “supplements that don’t have proven scientific benefit” is worth any potential risk.
And all the experts said that there are other, research-backed ways to extend your health and lifespan that have nothing to do with supplements.
“If you really want to know something that’s proven to change biologic ageing and epigenetic ageing,” Topol said, “it’s exercise.”
This article originally appeared in The New York Times.
Written by: Dana G. Smith
©2025 THE NEW YORK TIMES