The journal Nature Aging recently published the results of a population study evaluating inflammatory markers in four distinct parts of the world, suggesting that inflammation may not be a natural consequence of aging. Two industrialized populations were included in this study, with data drawn from the Italian InCHIANTI study and the Singapore Longitudinal Aging Study (SLAS), as well as two non-industrialized populations, the Tsimane from the Bolivian Amazon and the Orang Asli from Peninsular Malaysia. A panel of 19 cytokines was used to assess inflammation, including TNF-α, IL-6, IL-1RA, IL-1β, etc.
While the two industrialized populations had very similar findings, the two non-industrialized populations differed substantially. In these populations, the markers of inflammation more typically expressed (and often referred to as “inflammaging”) were not associated with aging or age-related diseases. It’s not that the non-industrialized populations did not have elevated markers of inflammation, but it was a pattern of inflammation associated with infections, such as bacteria or parasites, and that did not correspond with age or age-related disease. For example, approximately 2/3 of the Tsimane had a minimum of one infection with an intestinal parasite.
Although there are a number of limitations to this type of study, it is at least suggestive that inflammation itself, or at least some patterns of inflammation, may not be directly harmful or driving the aging process. It may be aspects of the industrial environment that promote both inflammation and chronic disease. For instance, air pollution and a number of environmental toxins have been associated with allergic inflammation as well as inflammation associated with chronic disease incidence.