Science Weekly: Geographic variations in microbes tied to obesity

Researchers at the University of California, Berkeley and the University of Arizona have made a discovery that people living in northern latitudes, which are colder regions, have bacteria in their guts that may make them targets for obesity.

The analysis of the microbes of more than 1,000 subjects from around the globe showed that the subjects living in the colder northern parts of the world have more bacteria that have previously been linked to obesity than the people living in the warmer southern hemispheres.

Researchers believed that although obesity tends to have negative connotations, it probably is vital to survival in such cold climates. Researchers think that what people think of as healthy microbiota may in fact differ from region to region.

The researchers have found a correlation between the ratio of Firmicutes and Bacteroidetes and obesity. The people with more Firmicutes than Bacteroidetes are prone to diseases such as diabetes, cancer and obesity. Slimmer people and mice seem to have more Bacteroidetes-dominant gut flora.

Some nutritionists believe tipping the ratio of Firmicutes to Bacteroidetes can help with weight loss.

Researchers also discovered that, with the increase in latitude, the proportion of Firmicutes increased and the Bacteroidetes decreased no matter the sex, age or race of the people. They think this is a piece of the puzzle that would otherwise be overlooked in the evolutionary pattern.

Information compiled from