Most recent update: Tuesday, May 23, 2017 - 15:27

Bariatric News - Cookies & privacy policy

You are here

Obesity paradox

Overweight and obese have higher risk of dying early

(Credit: Petr Kratochvil)
The findings contradict recent reports that suggest a survival advantage to being overweight - the so-called ‘obesity paradox’

Being overweight or obese is associated with a higher risk of dying prematurely than being normal weight—and the risk increases with additional pounds, according to a large international collaborative study led by researchers at the Harvard TH Chan School of Public Health and the University of Cambridge, UK. The findings contradict recent reports that suggest a survival advantage to being overweight - the so-called ‘obesity paradox’.

According to the authors of the study, ‘Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents’, published in The Lancet, recent studies that excess weight was beneficial serious methodological limitations. One common problem is called reverse causation, in which a low body weight is the result of underlying or preclinical illness rather than the cause. Another problem is confounding by smoking because smokers tend to weigh less than non-smokers but have much higher mortality rates.

"To obtain an unbiased relationship between BMI and mortality, it is essential to analyse individuals who never smoked and had no existing chronic diseases at the start of the study," said Dr Frank Hu, professor of nutrition and epidemiology at Harvard Chan School and a co-leader of the collaboration. Hu stressed that doctors should continue to counsel patients regarding the deleterious effects of excess body weight, which include a higher risk of diabetes, cardiovascular disease, and cancer.

In order to provide more definitive evidence for the association of excess body weight with premature mortality, researchers joined forces in 2013 to establish the Global BMI Mortality Collaboration, which involves o

Want more stories like this? Subscribe to Bariatric News!

Bariatric News
Keep up to date! Get the latest news in your inbox.