For years, scientists have believed that inflammation inevitably increases with age, quietly fuelling diseases like heart disease, dementia and diabetes. The same inflammatory molecules did not rise consistently with age, and they were not strongly linked to age-related diseases.
In fact, among the Tsimane, who face high rates of infections from parasites and other pathogens, inflammation levels were often elevated. Yet this did not lead to the same rates of chronic diseases that are common in industrialised nations.
Despite high inflammatory markers, the Tsimane experience very low rates of conditions such as heart disease, diabetes and dementia.
Inflammaging may not be universal
These results raise important questions. Instead, it may arise in societies marked by high-calorie diets, low physical activity and reduced exposure to infections.
In other words, chronic inflammation linked to ageing and disease might not simply result from an inevitable biological process, but rather from a mismatch between our ancient physiology and the modern environment.
The study suggests that in communities with more traditional lifestyles – where people are more active, eat differently and are exposed to more infections – the immune system may work in a different way. It could be happening at a cellular or tissue level, where it remains invisible to the blood tests used in this research.
Why this matters
If these findings are confirmed, they could have significant consequences.
First, they challenge how we diagnose and treat chronic inflammation in ageing. Findings from these groups cannot automatically be assumed to apply worldwide.
The researchers are clear: this study is just the beginning.
