People from non-industrialized Indigenous communities do not show the link between chronic inflammation and age-related illness that is seen in industrialized societies, finds a study that looked at nearly 3,000 adults in four countries. Inflammation is an important part of the immune system’s response to infection; however, long-term inflammation can cause damage. The latest findings, published in Nature Aging on 30 JUN 2025, show that chronic inflammation — which has been long considered a hallmark of ageing — could be a feature of industrialized living.
Researchers analyzed inflammation-linked proteins in blood samples from people living in Italy and Singapore, along with those from Indigenous participants living in non-industrialized or semi-industrialized communities in Bolivia and Malaysia. They found that inflammation levels increased with age and were linked with illnesses such as chronic kidney disease in the Italian and Singaporean groups. However, in the two Indigenous groups, inflammation did not increase with age or lead to health conditions.
This suggests that “our assumption that inflammation is an inexorable, inevitable part of ageing is not true”, says Thomas McDade, a Biological Anthropologist at Northwestern University in Evanston, Illinois. “We shouldn’t assume that the links between inflammation and ageing are universal.”
“We’re at a point where we’re rethinking the whole nature of inflammation,” says study co-author Alan Cohen, who researches ageing at Columbia University in New York City. “The things that we think of as universal, based on a lot of studies in Western industrialized populations, are probably just particular to our environment.”
Challenging assumptions
Much of what researchers know about the biological processes that underlie ageing is based on research in wealthy countries, which suggests that inflammation increases with age and can contribute to health conditions such as Alzheimer’s disease, diabetes and heart problems. However, these conditions are rare in non-industrialized populations.
To explore how inflammation might affect ageing in different environments, Cohen and his colleagues analyzed blood samples from 1,041 participants in Italy, 941 from Singapore, 536 Tsimane people from the Bolivian Amazon and 358 Orang Asli individuals from Peninsular Malaysia. More than 50% of the people in each group were female.
The researchers measured how levels of eight (8) proteins called cytokines — molecules released by immune cells that are involved in various types of cell signaling, including inflammation — changed with age in each group. They also examined whether high levels of the cytokines were associated with age-related health problems.
REFERENCE: Nature; 30 JUN 2025; Miryam Naddaf