New research from Arizona State University challenges the widespread belief that aging is always accompanied by increased inflammation, a phenomenon often referred to as “inflammaging.” The study, published in Proceedings of the Royal Society B, examined two communities in the Bolivian Amazon—the Tsimane and Moseten—and found that the experience of inflammaging varies based on lifestyle and environment.
Jacob Aronoff, a postdoctoral research scholar at ASU’s School of Human Evolution and Social Change, led the study. He is affiliated with the Institute of Human Origins and is a member of the Center for Evolution and Medicine. Aronoff and his team focused on whether age-related inflammation is universal among humans.
“To see if they develop inflammaging, we measured a collection of cytokines in a sample of older Tsimane adults to see if they increase with age — we found minimal increases with age,” Aronoff said.
The Tsimane people live across 90 villages in the lowlands of the Bolivian Amazon, maintaining a hunter-farmer lifestyle similar to pre-industrial societies. Past studies have indicated that this group has some of the healthiest hearts globally and among the lowest rates of Alzheimer’s disease and dementia.
Benjamin Trumble, senior author on the article and professor at ASU’s School of Human Evolution and Social Change, co-directs the Tsimane Health and Life History Project. This project has worked closely with the Tsimane community for over two decades to collect health data and provide medical care.
To broaden their analysis, researchers also studied the Moseten community. Although genetically similar to the Tsimane, the Moseten underwent significant cultural change after Jesuit missionaries settled among them about 300 years ago. Today, they have access to running water, electricity, and indoor plumbing—marking a moderate level of modernization compared to industrialized countries but more than what is seen among the Tsimane.
“They’re still the same genetic group, same language group, but the Moseten now have running water, electricity and indoor plumbing,” said Trumble. “They’re kind of in an in-between place where they aren’t as industrialized as people living in the U.S., but they aren’t as traditional as a population like the Tsimane that’s still living much more like most of our human ancestors.”
By measuring both groups using identical laboratory methods and technology, researchers observed more pronounced inflammaging among Moseten participants. According to Aronoff: “We measured them together in the same lab, using the same technology, and we found clearly more pronounced inflammaging in the Moseten, suggesting that inflammaging — to a large extent — is a product of industrialized lifestyles.”
The findings suggest that increased inflammation with age may not be inevitable but instead influenced by environmental factors such as diet and physical activity. Trumble noted: “For 99% of human history we were physically active hunter gatherers. Now, with sedentary urban city life, we are basically operating outside the ‘manufacturer’s recommended warranty’ right now.”
Another factor under consideration is exposure to parasites and pathogens—a common occurrence for communities like the Tsimane but rare in industrialized societies—which could play a role in immune system development related to inflammation.
“We’ve eliminated most of our parasites, and that’s a good thing. We should keep it that way,” Trumble said.
Trumble also discussed potential future approaches: “One of the things that we could do in the future potentially is… figure out what are the proteins on… hookworm cells — and what if we could turn that into a drug that people could take… Our immune system would think we had that problem… then it would develop differently to fight that off.”
While there are possibilities for new treatments inspired by these findings—similar to how vaccines work—Trumble cautioned against expecting simple solutions: “Ultimately… there is no ‘silver bullet,’ as lifestyle and diet are also likely major contributors to inflammaging.”
Aronoff added: “We have future studies underway to look at diets, physical activity and infectious exposures that… can have these anti-inflammatory effects. We’re going to have to do a lot of future studies to figure out what… are all the factors and how they work together.”
