Research shows being obese for longer period may increase risk of mortality

Monash University researchers have found the number of years individuals live with obesity is directly associated with the risk of mortality.

The research shows that the duration of obesity is a strong predictor of mortality, independent of the actual level of Body Mass Index (BMI). As the onset of obesity occurs earlier and the number of years lived with obesity increases, the risk of mortality associated with adult obesity in contemporary populations is expected to increase compared with previous decades.

Using data from the Framingham Heart Study, 5209 participants were followed up for 48 years from 1948. The current study however only included participants who were free from pre-existing diseases of diabetes, cardiovascular diseases and cancer.

The research showed that for those who had a medium number of years lived with obesity (between five years and 14.9 years), the risk of mortality more than doubled than for those who had never been obese. The risk of mortality almost tripled for those with the longest duration of obesity (more than 15 years).

Furthermore, the research showed for every additional two years lived with obesity, the risk of mortality increased by between six and seven per cent.

"Before now, we did not know whether being obese for longer was any worse for you health than simply being obese. However, this research shows for the first time that being obese for longer increases your risk of mortality, no matter how heavy you actually are," Monash University researcher, Dr Anna Peeters said.

"This research provides added support for all the current policy trying to prevent obesity in general. It also indicates that we should try extra hard to prevent obesity at younger ages," said Dr Peeters.