Being plump may not be so bad after all!

A bit of extra weight could actually help you live longer, according to new research which found that men and women who are slightly plump have longer lives than those who are slimmer.

US researchers analysed results of almost 100 studies and found that those judged to be slightly overweight were 6 per cent less likely to have died by the end of the study period than those of normal weight.

However, those who were any bigger were around a third more likely to die during the months or years they were being studied than those of normal weight.

The analysis is not the first to suggest that a bit of extra weight is actually good for health.

Explanations as to why this might be include the possibility that those who start out slightly heavier will have more fat reserves to call on should they lose weight due to ill health as they get older, researchers believe.

It is also possible that concerns about the health of the overweight and obese means that problems linked to weight, such as high blood pressure and diabetes, are more likely to be spotted and treated, improving that person`s overall health.

It has also been suggested that some people`s genes may help them escape the health consequences of being slightly overweight, while a bit of extra padding could help the elderly to survive falls unscathed.

Another theory is that some of those who are overweight may actually exercise more and eat better than thin people who starve themselves or smoke to suppress their appetite.

For the latest study, US government researchers read 91 previous research papers on the topic from around the world involving millions of men and women.

They looked at the subjects` body mass index (BMI) at the start of the research and how likely they were to have died by the end of it.

People are classified as being of normal weight if they have a BMI of between 18.5 and 24.9 and overweight if their reading is between 25 and 29.9.

A BMI higher than this is classified as obese and the bigger the reading the greater the risks to health are thought to be.

Having a BMI of between 30 and 34.9, and so being slightly obese, also did not seem to harm health.

However, those whose BMI was greater than this were 29 per cent less likely to live to see the end of the study than those whose weight was classed as normal.

The study was published in the Journal of the American Medical Association.