The inflammation paradox: Why are Tsimane protected against Western diseases while Westerners are not?

Recently, observational studies in the Amazon region showed that the indigenous Tsimane in Bolivia appear protected against non-communicable diseases (NCDs) such as obesity, type 2 diabetes, and cardiovascular diseases despite increased inflammatory markers. These findings stand in contrast to Western societies, where an increasing body of evidence demonstrates that low-grade-inflammation is the driver of NCDs. In 2013 and 2014, we carried out two field studies (Eifel studies) with Westerners who returned to a simulated Palaeolithic lifestyle in a National park for 4 days and detected elevated inflammation markers, analogous to the conditions of the Tsimane. We here propose three hypotheses for this inflammatory paradox.