Diet and exercise habits help people maintain a healthy body weight, which the Circulation study defined as a body mass index between 18.5 and 24.9. Obesity is associated with chronic conditions including Type 2 diabetes, cardiovascular disease and cancer, all of which can shorten your life. A 2018 study found that widespread obesity shaved a year off the U.S. life expectancy and is responsible for up to 186,000 deaths per year.
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