A study out of the Harvard Medical School in Boston found that Facebook statuses could accurately predict how healthy regions of the United States were. Researchers cross referenced information about the content of people's Facebook statuses and cross-referenced them with obesity statistics from Centers for Disease Control and Prevention (CDC) Behavior Risk Factor Surveillance survey and the New York City Community Health Survey (CHS).

The study indicated that in areas that people tend to write about healthy food and good habit choices. Regions that had higher obesity rates were correlated with people posting about unhealthy interests such as television watching.

The researchers concluded that "Activity-related interests across the USA and sedentary-related interests across NYC were significantly associated with obesity prevalence."

"Higher proportion of the population with activity-related interests on Facebook was associated with a significant 12%...lower predicted prevalence of obese and/or overweight people across USA metros and 7.2%...across NYC neighborhoods,"

People tend to reveal a lot about themselves by not only how they write but the content of what they write. In a world where we are posting everything we do online, a lot of information can be gleaned about who we are in the real world.

Obesity versus TV watching Facebook status' Chunara R, Bouton L, Ayers JW, Brownstein JS (2013) Assessing the Online Social Environment for Surveillance of Obesity Prevalence. PLoS ONE 8(4): e61373. doi:10.1371/journal.pone.0061373

Obesity rates in the US versus Facebook status .Chunara R, Bouton L, Ayers JW, Brownstein JS (2013) Assessing the Online Social Environment for Surveillance of Obesity Prevalence. PLoS ONE 8(4): e61373. doi:10.1371/journal.pone.0061373

The study published in PLoS One can be found here.