There is a prevailing thought amongst some in the microbiome field that the 'Westernized' diet and lifestyle is responsible for many diseases that are not observed in traditional societies, which are afflicting a growing population. Unfortunately, it is somewhat difficult to study how the 'Western' microbiome has changed because most of the world’s population could be considered to have this microbiome. Fortunately, there are still some societies that forage for their own food and have had a consistent diet for much of their history. The belief is that these 'traditional' societies have microbiomes that better resemble those of ancient peoples, and by unlocking the mysteries of these people’s microbiomes we can better understand these 'Western' diseases.
With this in mind, scientists from the University of Oklahoma studied the microbiomes of three groups of people with three different dietary habits: the Matsés hunter gatherers from Peru, the Tunapuco agriculturists from the Andes, and the residents of Norman, Oklahoma. The Matsés ate primarily fish and meat along with many vegetables, the Tunapuco ate primarily potatoes and other roots along with small game, and the Oklahomans followed a typical Western diet. The researchers found that both traditional societies had much higher microbiome diversities than the Oklahomans. While each society had different comprised of different species of bacteria, interestingly, both traditional societies had higher levels of the genus Prevotella and Treponema than Oklahomans, who themselves were richer in Bacteroides.
Interestingly, Treponema are rarely seen in the microbiomes of Westerners, which may lead to the belief that these were important symbionts to our ancestors. Nevertheless, there were many similarities between the all the microbiomes as well. According to this study there is little doubt that our microbiomes have changed immensely in modern history. How these changes may be related to so-called ‘diseases of wealth’, though, is still an open question.