Chronic inflammation is not a sign of aging, but a product of lifestyle in industrialized countries – this is what a new study claims

It's been proven that as we age, more and more small inflammations develop in our bodies. These are involved in the development of cardiovascular disease, type 2 diabetes, and even joint problems. However, an international team of researchers now claims in the journal "Nature Aging" that chronic inflammation doesn't automatically occur with age. Rather, it's a consequence of the lifestyle in industrialized countries.

This was revealed by tests of more than a dozen inflammatory markers in the blood. For the new study, both Italians in the Chianti region and residents of Singapore were examined as representatives of the industrial lifestyle. Blood samples from completely different groups, the Orang Asli from Malaysia and the Tsimané from the Bolivian Amazon region, were analyzed.

Special molecules, so-called inflammatory factors, produced by the immune system, were measured. These factors indicate whether there are acute or chronic inflammations in the body. As expected, the subjects from industrialized countries showed clear signs of chronic inflammation with increasing age. They also suffered more frequently from the aforementioned diseases.

The situation was completely different for the two indigenous groups. While the vast majority of subjects from Bolivia and Malaysia suffered from acute infections caused by bacteria, viruses, or parasites, they showed almost no signs of chronic inflammation. Furthermore, they exhibited very few of the aforementioned age-related illnesses.

The authors conclude that inflammation does not generally occur with increasing age, but is triggered by lifestyle and environment.

"I consider this conclusion very bold," says Burkhard Becher, an immunologist at the University of Zurich, in an interview. While the data are interesting, they don't support this interpretation. He believes some of the methods used are not precise enough. "I wouldn't say that lifestyle alone influences disease and inflammation, while age plays no role at all."

Numerous mouse studies show that changes in the immune system, age-related diseases, and chronic inflammation do occur with age. Since all the animals ate the same boring, normal food, and none of the mice were given cola and hamburgers, lifestyle isn't solely responsible. However, Becher finds it entirely plausible that lifestyle in humans has a significantly greater influence on disease and inflammation than previously thought.

Chiara Herzog, who works at the Institute for Biomedical Aging Research at the University of Innsbruck, is also skeptical that the entire concept of increasing inflammation with age needs to be thrown out the window. In any case, the new study confirms that typical inflammatory patterns emerge with increasing age in industrialized countries, she explained to the Science Media Center. And that these are associated with chronic diseases in old age. "This strengthens the assumption that certain living conditions in industrialized societies promote these processes."

After all, we are by no means helpless in the face of these developments. Experts believe it is proven that both a lack of exercise and a high-calorie diet promote the aforementioned age-related diseases. In this respect, the Zurich immunologist, Herzog, and other researchers agree with the study authors that we humans can influence whether we develop one of the typical diseases associated with chronic inflammation as we age.

While none of the experts recommend moving to the jungle and living a life far removed from civilization—and thus forgoing the blessings of modern medicine—people in industrialized countries can certainly achieve a lifestyle that is considered healthy. This means regular exercise and eating plenty of fresh vegetables and fruit, whole grain products, nuts, legumes, and sufficient protein, and, ideally, maintaining regular social contacts.

Becher is convinced, however, that a diet considered healthy doesn't directly influence the immune system. "Yes, it prevents cardiovascular disease and other age-related diseases associated with inflammation," he says. But not by normalizing the immune system. Rather, a healthy diet has positive effects in other ways, for example, by reducing the accumulation of harmful metabolic products in organs.

In his opinion, the immune system usually only triggers inflammation when something is wrong in an organ, for example, when the elimination of toxins or diseased cells is no longer functioning. In other words, the immune system is reacting to an unhealthy condition.

Therefore, the immunologist considers powders or tablets, as well as food additives, touted as anti-inflammatory to be pointless, possibly even counterproductive. Inflammation is generally a good defense reaction of the body, he says. Therefore, in many types of cancer, doctors deliberately stimulate the immune system with medications so that it destroys the degenerated cells.

Becher emphasizes that it is by no means proven that the small, chronic inflammations that occur in old age are the cause of the disease. However, it is quite possible that they are the side effects of a previously occurring disorder. Therefore, one should not attempt to suppress the immune system. Instead, the cause of the disorder must be identified and then treated specifically.

The new study raises doubts about the role inflammation plays in old age. Thus, it cannot provide a prognosis for health in old age or even life expectancy, as some geriatricians hope.