CHICAGO, IL (WOWO) A large international study is raising new questions about when weight gain may pose the greatest long-term health risks, suggesting that obesity beginning in early adulthood could be more dangerous than weight gained later in life.

Researchers analyzed data from more than 620,000 people and found that individuals who became obese between the ages of 17 and 29 faced a significantly higher risk of premature death compared to those who developed obesity later, according to eClinicalMedicine.

The study, which drew from long-term health tracking data, found that early-onset obesity was associated with nearly a 70 to 80 percent increase in risk of early death. Researchers noted that while obesity beginning between ages 30 and 60 was also linked to higher mortality, the association was weaker.

Researchers say one possible explanation is the length of exposure to obesity-related health effects, including strain on metabolic and cardiovascular systems over several decades.

“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,” researchers said in findings associated with the study.

The analysis also pointed to conditions such as type 2 diabetes as a leading factor associated with early-onset obesity, along with elevated risks of high blood pressure and certain cancers, depending on sex and other variables.

Researchers caution that while the trends are significant across populations, individual risk can vary widely depending on lifestyle and other health factors. They also note that further research is needed to determine whether the same patterns hold in populations outside of Sweden, where much of the data was collected.

The findings add to ongoing research into how the timing of weight gain may influence long-term health outcomes and disease risk.