Do people who live past 100 have something different in their blood?
Yes. In this study of people who reached extreme old age, researchers found a distinct chemical “fingerprint” in their blood, with higher levels of certain bile acids and lower levels of two waste pigments. These same patterns were tied to a lower risk of dying.
The work comes from the New England Centenarian Study, one of the largest efforts to understand why some people live far longer than most. Researchers used a method called untargeted metabolomics. In plain terms, they measured more than 1,400 tiny chemicals in the blood at once, then looked for patterns that set the longest-lived people apart from everyone else.
What the data show
The study measured over 1,400 blood metabolites in 213 people from the New England Centenarian Study. To make sure the findings held up, the team then compared their results with metabolomic data from four other studies. That kind of validation matters, because a pattern seen in one small group can vanish when you look at a different one.
People who reached extreme old age stood out in a few clear ways. Compared with their own children and with matched controls of a similar background, they carried higher levels of primary and secondary bile acids. The two that stood out most were chenodeoxycholic acid and lithocholic acid. At the same time, they had lower levels of biliverdin and bilirubin, two pigments the body makes when it breaks down old red blood cells. Their levels of certain steroids stayed steady rather than falling.
The most striking part was what these chemicals predicted. Higher levels of both the bile acids and the steroids were linked to a lower risk of dying. In other words, these were not just markers of old age, but signals that tracked with survival.
Dr. Kumar’s Take
What I find fascinating here is where the trail leads. Bile acids are made in the liver, but they are heavily shaped by the bacteria living in your gut. So this study is quietly pointing at the gut as a player in human longevity, not just the liver or the brain. That fits a growing body of work, and it gives us real chemical targets to study rather than vague advice. I want to be clear about the limits, though. This is an association study. It shows that long-lived people carry these patterns, not that raising your bile acids will add years to your life. Bile acids in the wrong amounts can also be harmful, so nobody should be chasing supplements based on this. What it does give us is a map of pathways worth investigating.
How it works
Several of the chemicals tied to age and survival pointed toward familiar biology. Some were linked to NAD+, a molecule your cells need to make energy and repair themselves. The team tracked this through metabolite ratios such as tryptophan to kynurenine and cortisone to cortisol. Others pointed to gut bacterial metabolism, seen in ratios like ergothioneine to TMAO and aspartate to quinolinate. A third group reflected oxidative stress, the everyday wear and tear from unstable molecules, captured by the ratio of methionine to methionine sulfoxide.
The researchers also built something they call a metabolomic clock. This tool uses blood chemistry to estimate a person’s biological age, which is how old the body acts rather than how many birthdays it has had. When a person’s estimated age drifted away from their real age, that gap tracked with their risk of dying. Some chemicals that powered this clock, such as taurine and citrate, did not show up in older, simpler age analyses, which suggests they may be useful new markers for healthy aging.
Practical Takeaways
- Treat this as early science, not a to-do list. There is no proven way yet to copy the blood chemistry of centenarians, and no supplement has been shown to reproduce these effects safely.
- Support your gut bacteria through everyday habits, since the gut helps shape the bile acids this study highlighted. A diet rich in fiber, plants, and fermented foods is a reasonable, low-risk approach.
- Ask your doctor before taking bile acid or steroid supplements, because the wrong dose can cause real harm and this research does not endorse taking them.
- Focus on the fundamentals that already have strong evidence, such as regular exercise, good sleep, and not smoking, while researchers work out whether these pathways can be targeted safely.
Related Studies and Research
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FAQs
What are bile acids and why do they matter for aging?
Bile acids are chemicals your liver makes from cholesterol to help you digest fat. After they do that job, gut bacteria change some of them into new forms called secondary bile acids. This study found that people who lived to extreme old age carried more of both types, and that higher levels were tied to lower mortality. That hints these chemicals may act as signals in the body, not just digestive helpers, though this research cannot prove they directly cause longer life.
What is a metabolomic clock and how is it different from my real age?
A metabolomic clock is a tool that estimates your biological age from the mix of chemicals in your blood. Biological age reflects how worn or resilient your body is, which can differ from the number of years you have lived. In this study, when a person’s estimated age was younger than their real age, they tended to have a lower risk of dying, and when it was older, the risk was higher. It is still a research tool, not something you can order at a routine checkup.
Can I change my blood metabolites to live longer?
Right now, no one can promise that. This study shows a link between certain blood chemicals and long life, but a link is not proof that changing those chemicals will help. Because the highlighted bile acids are shaped by gut bacteria, habits that support a healthy gut, like eating fiber and fermented foods, are reasonable and low risk. What you should not do is take bile acid or steroid supplements on your own, since the wrong amount can be harmful and this research does not support that step.
Bottom Line
People who reach extreme old age carry a distinct chemical signature in their blood, marked by higher primary and secondary bile acids such as chenodeoxycholic and lithocholic acid, lower biliverdin and bilirubin, and steady steroid levels, with several of these patterns tied to lower mortality across five combined studies. By building a metabolomic clock and linking it to survival, the researchers point to bile acids and gut metabolism as promising pathways for healthy aging, even though it is far too early to turn these findings into treatments.
