In collaboration with dozens of research institutions from around the world, scientists from the National Cancer Institute have discovered that there may be an increased risk of death for people who are overweight and obese.

According to the National Institute of Diabetes and Digestive and Kidney Diseases, more than two-thirds of Americans who are aged 20 and older are either overweight or obese.

The investigators analyzed the data from 19 long-term studies that had been previously conducted. Overall, there were 1.5 million men and women involved with the research.

In the findings, women who were overweight – and had never smoked – were 13 percent more likely to die compared to those with a healthy weight. Women who were severely overweight were at a higher risk for death. Specifically, among both the men and women, each time there was a five unit increase in a subject’s body mass index, there was also a 31 percent increase in risk of death.

The scientists noted that smoking and pre-existing illnesses also increased the subjects risk of death.

The Centers for Disease Control and Prevention reports that individuals should eat fruits, vegetables, calcium-rich food and also engage in physical activities to maintain a healthy weight.