COLUMBUS (WCMH) — A new study from the Ohio State University says gradually gaining weight could be the key to a longer life.  

According to the study, people who start adulthood with a body mass index (BMI) in the normal range and move later in life to being overweight, but never obese, tend to live the longest.

“The impact of weight gain on mortality is complex. It depends on both the timing and the magnitude of weight gain and where BMI started,” said Hui Zheng, lead author of the study and associate professor of sociology at The Ohio State University. “The main message is that for those who start at a normal weight in early adulthood, gaining a modest amount of weight throughout life and entering the overweight category in later adulthood can actually increase the probability of survival.”

OSU says similar results were found in two generations of mostly white participants in the Framingham Heart Study, which followed the medical histories of residents of one city in Massachusetts and their children for decades.

However, the study showed worrying trends for the younger generation, who are becoming overweight and obese sooner in their lives than their parents did and are more likely to have deaths linked to increasing obesity.

The researchers used data on 4,576 people in the original cohort of the Framingham Heart Study, and 3,753 of their children. The heart study started in 1948 and followed participants through 2010. Their children were followed from 1971 to 2014.

The members of the original cohort had almost all died by the end of the study, so the results can uncover how BMI evolves over all of adulthood and provide a more accurate estimate than previous studies of how obesity is linked to mortality, Zheng said.

In both generations, the researchers looked at data from those aged 31 to 80. The main measure was BMI, which is based on a person’s height and weight and is used as a rule of thumb to categorize a person as underweight, normal weight, overweight or obese.

To read more about the study go to: Annals of Epidemiology.