Researchers using smartphones to track the activity levels of people around the globe discovered that in countries with little obesity, people 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

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Researchers using smartphones to track the activity levels of people around the globe discovered that in countries with little obesity, people 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