There is a recent PLoS ONE article on obesity getting quite a bit of attention. The article,
Hunter-Gatherer Energetics and Human Obesity, reports research looking at total energy expenditure in a sample of adults from a Tanzanian hunter-gatherer tribe, the Hadza. Given their “traditional physically active lifestyle” the authors expected that Hadza to have lower body fat and to expend more energy than modern, Western populations, and the aim the research was to see if this was in fact true.