WIKIMEDIA, HAPLOCHROMISBrown bears (Ursus arctos) hibernate for up to six months each year. Before hibernating, bears double their fat stores, becoming what scientists call “seasonally obese.” Researchers have now shown that the secret to healthy weight gain may lie in the bears’ gut microbiota, which also vary seasonally. Their findings were published last week (February 4) in Cell Reports.
“We know that the microbiota is very responsive to what we eat. So if a bear eats a lot in the summer and it doesn’t eat in the winter, then there should be an altered microbiota,” study coauthor Fredrik Bäckhed of the University of Gothenburg, Sweden, told BBC News. “What we learn from our study is that it appears that the altered microbiome can contribute to the altered adiposity (fattiness).”
The researchers collected fecal samples from wild brown bears in February (when the bears were hibernating) and in June (when the bears were active). They then colonized germ-free mice with microbial samples from each season.
“What we found was that if we colonized the mice with the summer bear microbiota, the mice gained more adiposity ...
