It’s no secret that our bodies change as we get older. The things we notice — joint pain, graying hair, wrinkles, and the rest — are mostly annoyances. But what goes on in our gut can have a real impact on our health and longevity.
The gut harbors most of the immune system, and it’s a sad biological fact that our immune response loses its effectiveness as we get older. Until recently, though, scientists have not been able to pinpoint exactly why. A new study now points directly at changes that take place in the aging gut.
The body produces an immune-system regulator called interleukin 6 (IL-6) in response to microbes attacking the gut, a process that produces inflammation. But researchers at the Institute of Food Research in the U.K. and the University of Siena in Italy found that older people they tested produced more IL-6 than younger study participants. That surplus of IL-6 creates unnecessarily high levels of gut inflammation that a raft of studies have shown accelerate the aging process.
“Inflammation is increasingly being seen as a key event behind aging, and our results suggest a pivotal role for the gut in this ‘inflammaging,'” study coauthor Claudio Nicoletti said in a statement released by the IFR.
Why this occurs in older people may be related to the microbes that colonize the gut as we age, Nicoletti explained. The profile of these microbes are different in younger people and interact differently with the gut lining and the cells of the immune system, including those cells that produce IL-6.
“Understanding the triggers will help us better understand what caused the changes observed in this study, and find ways of preventing them,” Nicoletti said. “If the gut bacteria are implicated in this, it opens up the possibility that we can manipulate these through probiotics, as a way of keeping us healthy as we get older.”
Meanwhile, no matter what your age, you can boost your immune system with regular exercise, plenty of sleep, and various stress-management practices. For more tips on sustaining a healthier immune system, see “The Best Defense: Boost Your Immune System” in our October 2007 issue.