∞ Stanford Researchers Find Intriguing Clues About Obesity by Counting Steps via Smartphones
From Stanford News by Tom Abate:
Stanford researchers using smartphones to track the activity levels of hundreds of thousands of people around the globe made an intriguing discovery: In countries with little obesity, people mostly walked a similar amount per day. But big gaps between people who walked a lot and those who walked very little coincided with much higher levels of obesity.
One interesting graph came out from the research, China is so blue:
Note the graph above is not the point of the paper, which says obesity can be predicted by activity inequality, not average. See their website for more information.