When people gain weight during life can shape their health decades later. In a study of more than 600,000 individuals, researchers at Lund University in Sweden examined how weight changes between ages 17 and 60 relate to the risk of death from various diseases. The findings point to a clear trend: weight gain in early adulthood appears to have the strongest long-term effects.
Obesity has long been linked to a higher risk of many diseases. This study shifts the focus by exploring how weight changes across adulthood, rather than weight at a single point, influence health outcomes.
“The most consistent finding is that weight gain at a younger age is linked to a higher risk of premature death later in life, compared with people who gain less weight,” says Tanja Stocks, Associate Professor of Epidemiology . She is one of the researchers behind the study.
The analysis draws on data from more than 600,000 people tracked through national records. To be included, participants needed at least three recorded weight measurements, such as during early pregnancy, at military conscription, or in research settings. Over the study period, 86,673 men and 29,076 women died.
The analysis draws on data from more than 600,000 people tracked through national records. To be included, participants needed at least three recorded weight measurements, such as during early pregnancy, at military conscription, or in research settings. Over the study period, 86,673 men and 29,076 women died.
Early Weight Gain Carries Higher Risk
Researchers examined how body weight changed from ages 17 to 60 and how these changes related to overall mortality and deaths linked to obesity-related diseases (see fact box). On average, both men and women gained about 0.4 kilograms per year (about 0.9 pounds per year).
Those who gained weight more quickly during adulthood faced a higher risk of death from the diseases studied. People who first developed obesity between ages 17 and 29 had about a 70 percent higher risk of premature death compared with those who did not develop obesity before age 60. Obesity onset was defined as the first time a person’s body mass index, a measure based on weight and height (kg/m²), reached 30 or higher.
“One possible explanation for why people with early obesity onset are at greater risk is their longer period exposed to the biological effects of excess weight,” says Huyen Le, a doctoral student at Lund University and the study’s first author.
