[Photo by Zhang Tao/Asianewsphoto]

Weight gain from early adulthood to age 55 may increase the risk of chronic diseases, premature death, and decreased the likelihood of achieving healthy aging, according to a study published Tuesday by the US journal JAMA.

"Our study is the first of its kind to systematically examine the association of weight gain from early to middle adulthood with major health risks later in life," said senior author Frank Hu, professor of nutrition and epidemiology and chair of the Department of Nutrition at the Harvard University.

"The findings indicate that even a modest amount (2.5 to 10 kg) of weight gain may have important health consequences."

Obesity is a major global health challenge. The worldwide prevalence of obesity was 11 percent for men and 15 percent for women in 2014 compared with five percent for men and eight percent for women in 1980.

Among US adults, the average weight gain is 0.5 to 1.0 kg per year from early to middle adulthood and this modest yearly accumulation of weight eventually leads to obesity over time.

However, it is unclear how weight gain during the transition from early to middle adulthood, when most weight gain occurs, relates to subsequent health consequences, such as type 2 diabetes, hypertension and cardiovascular disease.