Obesity is a growing concern; today, experts class well over one-third of people in the United States as obese.
Globally, an estimated 4 million people died of conditions related to a high body mass index (BMI) in 2015 alone.
These worrying trends mean scientists are focused on understanding the causes, risk factors, and implications of obesity.
The reason why obesity develops in certain people and not others is multifaceted, involving genetic, hormonal, and psychological factors, among others.
