Metformin May Delay Aging Process

The oral diabetes drug metformin may slow the aging process by mimicking the effects of a calorie-restricted diet, according to a new animal study from the United Kingdom. Metformin is believed to be the most commonly prescribed diabetes medicine in the world, with over 48 million prescriptions written in 2010 in the United States alone.

Calorie restriction has been shown, in some cases, to improve health and lengthen life in animals ranging from worms to rhesus monkeys. Similar effects have been noted with the use of metformin, but it has not been clear how the drug might help delay the aging process.


To determine how metformin slows aging, researchers looked at the effects of the medicine on C. elegans worms that were exposed to and colonized by E. coli bacteria — the relationship between these two organisms is similar to that which humans have with healthful bacteria in their gut. (Studies have found that “good” gut bacteria help their host digest and extract nutrients from food, and defects in these bacteria have been linked to metabolic conditions such as Type 2 diabetes and obesity.)

The results showed that the worms lived longer only when the E. coli strain they had been cultured with was sensitive to metformin. In these cases, the worms lived an average of six days longer than usual, equivalent to a third of their normal lifespan.

The researchers discovered that metformin slowed the aging process by altering the metabolism of the E. coli bacteria — specifically, by disrupting the bacteria’s ability to metabolize folate, a type of B vitamin, and methionine, a building block of protein — thereby limiting the nutrients available to the worm, mimicking the effects of a calorie-restricted diet.

When the team added excess sugar to the worms’ diets, however, the life-extending benefits of metformin were cancelled out, a finding that could be particularly relevant for determining how the medicine works in humans.

“We don’t know from this study whether metformin has any effect on human aging. The more interesting finding is the suggestion that drugs that alter bacteria in the gut could give us a new way of treating or preventing metabolic diseases like obesity and diabetes,” noted David Gems, PhD, who directed the research.

In a related study, this one conducted at the University of Montreal, investigators found that metformin may slow the aging process and cancer progression by reducing the production of inflammatory cytokines, a component of the immune system that helps fight infection. (When cytokines are overproduced, it leads to chronic inflammation that is involved in both the aging and cancer processes.) Specifically, metformin disrupted a protein that would typically trigger activation of the immune system.

To learn more about the research looking at metformin and C. elegans, read the article “How Diabetes Drug Delays Aging in Worms” or see the study’s abstract in the journal Cell. And to learn more about metformin, click here.

  • jim snell

    fascinating study/comments.

    Metformin continues to amaze. More curious isthat metforming has to be acting as catalyst/signalling and no breakdown components have been discovered on metformin leaving the body as it came chemically.

  • Deb

    I like this! It’s worth the side effects to help my battered immune system!

  • Tintin

    Deb – What are your side effects? How does it help your immune system? What dose and form (regular or sustained release) are you using?


  • rmt

    I hope those taking metformin are also taking B12. At any sign of dry skin or (upset stomach), I take methylcobalamin (activated B12) and the dry skin/upset stomach goes away.

  • Rosa Beam

    I had very serious to metformin after been taking it for several years. I really would like to go back to metformin instead having shots of insulin. Another great motivation for me is the cost!

  • Pam Schmidt

    The side effect most people notice when first starting Metformin is weight loss. Not a lot, but more than before taking it. I take the lowest dosage at 1 500mg twice a day, but I know people who take higher doses have considerably more weight loss. Some GI symptoms are common when first starting Metformin, but those side effects diminish over a short period of time. My support groups diabetes nurse advises us to take probiotics which ties in with the information in the above article also.

  • Joe

    After starting Metformin, I became deficient in several nutrients including vitamin D, several B vitamins, calcium, magnesium, and Iron. I now live on supplements.

  • ted plottner

    i take extra folate and beta-glucan—maybe my metformin is neutralizing thes supplements or delaying there action?????????I knew of metformins anti ageing action over 5 years ago…upon reading experiments at a small Calif. bio-tech firm—–This info did not originate where you say it did

  • Laverne

    Why is it that all these studies are done in other countries. Where is all the money going for our research?????

  • Stuart

    Does this mean I should not be taking Folate supplements, in addition to B-12?

  • Marsha

    Yes, it would be good if someone could identify the appropriate supplements for people on Metformin as I think many would like to take supplements, but unsure of what exactly they should take and the appropriate dosing.

  • Fern Byer

    Talk to your LOCAL INDPENDENT P harmacist. They can tell you what supplements to take with the meds you are taking.
    Any pharmacist can tell you, the big box store Pharmacist don’t have time and are often not encouraged to take the time to tell you.

  • Valerie

    And that is because at independent pharmacies you are dealing with the owner, not true at the big box stores. And that means a lot to most patients.