Inuit microbiota withstands the test of time
Considering that eating habits are one of the main factors impacting the composition of the intestinal microbiota, researchers from Quebec wanted to study the impact of seasonal diet changes on this microbiota.
The researchers traveled to Nunavut, the northernmost territory of Canada. The Inuit who live there are hunter-gatherers and their traditional diet is based on the consumption of game, fish and wild birds, whose availability depends on the season and which are becoming scarce as a result of global warming. Moreover, their eating habits are influenced by the western lifestyle: although they still favor food obtained through hunting and fishing in summer, they readily turn towards supermarket products during fall. On the contrary, western eating habits are barely subjected to seasonal influences since food products are available almost constantly.
Microbiota and temporal fluctuations
To characterize temporal variations in the intestinal microbiota induced by the Inuit traditional diet, the researchers analyzed the microbiota of fifteen Nunavut inhabitants and compared it to that of nine people living in the city of Montreal, based on stool samples collected during a period of nearly one year. Although no significant seasonal difference was observed, the composition of the Inuit microbiota experienced more changes over time. According to the researchers, this finding suggests that the Inuit microbiota is shaped by a more variable diet, and that it is dependent on hunting and on the prices of imported goods.
Nunavut - Montreal: same microbiota?
Although the microbiota diversity was just as high in both communities, the researchers noted differences in its composition: Inuit microbiota reflects a high consumption of coffee, raw meat and fish, whereas that of Montreal inhabitants is the result of a higher consumption of fruits and vegetables, cooked meat and alcohol. According to the researchers, between 11% and 17% of microbiota variations could be attributed to eating habits. The authors concluded that although western diet is becoming more frequent in Inuit populations, their traditional diet still has a strong impact on their microbiota composition, diversity and stability.
Dubois et al. The Inuit gut microbiome is dynamic over time and shaped by traditional foods. Microbiome (2017) 5:151 DOI 10.1186/s40168-017-0370-7