Bacteria from lean mice prevents obesity in peers

But microbes are only part of the story — the effect also depends on a healthy diet.

Gut bacteria from lean mice can invade the guts of obesity-prone cage-mates and help their new hosts to fight weight gain.

Researchers led by Jeffrey Gordon, a biologist at Washington University in St. Louis, Missouri, set out to find direct evidence that gut bacteria have a role in obesity.

The team took gut bacteria from four sets of human twins in which one of each pair was lean and one was obese, and introduced the microbes into mice bred to be germ-free. Mice given bacteria from a lean twin stayed slim, whereas those given bacteria from an obese twin quickly gained weight, even though all the mice ate about the same amount of food. Read more in Nature.

Heavy sleepers

A growing body of evidence shows that getting a good night’s sleep plays an important role in regulating the body’s metabolism.

Burning the midnight oil can leave you tired and grumpy the next day, dulling your mind and slowing your reaction times. But lack of sleep has consequences beyond the brain as well, with long-term sleep disturbances leading to metabolic problems.

Matthew Brady, a biologist at the University of Chicago in Illinois who studies the links between sleep and metabolism, puts it simply: “Fat cells need their sleep as well.” Read more in Nature.