News, views and top stories in your inbox. Don't miss our must-read newsletter Sign up Thank you for subscribing We have more newsletters Show me See our privacy notice Invalid Email

Obesity can shorten life expectancy even after weight loss, new research has found.

Scientists say death rates among those who were formerly obese or overweight were considerably higher than those had never exceeded normal weight.

This illustrates that obesity at any age can cause illness, regardless of whether the weight is kept on, they say.

Failure for this to be reflected in official studies "obscures the benefits" of never becoming overweight at all, the researchers claim.

Scientists from the Boston University School of Public Health and University of Pennsylvania analysed data from 6,000 Americans and found there was "exceptionally high mortality among those who lost weight".

(Image: Getty)

The report showed that those who were never above normal weight had a mortality rate of 6.25 per 1,000, while those who were formerly overweight had a rate of 10.81 and those formerly obese of 14.62.

In England, figures from the Health Survey for England show that around 62.1% of adults were overweight or obese in 2013.

By 2050 obesity is predicted to affect 60% of adult men, 50% of adult women and 25% of children.

Read more:

Previous surveys have distorted how dangerous weight-gain can be, as many fail to record an individual's maximum-ever body mass index (BMI), according to the authors.

The report, published in the Proceedings of the National Academy of Sciences journal, said: "These distortions make overweight and obesity appear less harmful by obscuring the benefits of remaining never obese.

"Obesity at a particular age may predispose illness, regardless of weight at higher ages.

"Our results suggest the burden of overweight and obesity on mortality is likely substantially larger than commonly appreciated."