10,000 steps a day? Largest fitness app study reveals why the US is fatter than Mexico

Enter the largest such study of this kind that was just released in the wild by Stanford researchers. It uses donated data from the Argus app to analyze the activity habits of no less than 717,527 people from 111 countries. That's a huge dataset, impossible to collect prior to phone-based health apps, and it was used to determine activity distribution by country, amount of movement, and body mass index, as all other data was anonymized by the donor app.

The study crunchers found out some interesting data - if you look at the map above, for instance, both US and Mexico participants took a similar number of steps per day on average, yet the body mass index of the Americans is higher than of the Mexicans, which are no lean meat to begin with. To explain this phenomenon, the researchers came up with what they dubbed "activity inequality." 

It turns out that there is a big difference in daily step count between the most active and the most sedentary people in the US. That activity gap led to the higher average obesity rates that was gleaned from the US data, so it looks like everyone walking 4500 steps a day (the average for both US and Mexico), is more important than a few walking 10,000+ steps, and the other few barely moving throughout the day, as is the case in the US. Thanks, smartphones, for aiding the largest activity study of this kind to reconfirm again how fat we are. Oh, and just look at the Chinese - now that's a nation on the move!

source: Stanford