People who recognise they are overweight or obese are more likely to put on weight than those who are unaware that they may be heavier than doctors would advise, according to research by the University of Liverpool.
In a study, published in the International Journal of Obesity, researchers looked at the lives of 14,000 adults in the US and the UK through data captured in three studies: the US National Longitudinal Study of Adolescent to Adult Health, the UK National Child Development Study and Midlife in the United States.
They analysed data from time periods after the children had reached adulthood to find out their perception of their own weight - whether or not it was correct - and their subsequent weight gain over time.
The UK study followed participants from 23 until 45, but the other two studies had shorter follow-up periods, of seven years and nine to 10 years.
They found that, those who identified themselves as being 'overweight' were more likely to report overeating in response to stress and this predicted subsequent weight gain.
Dr Eric Robinson, from the University's Institute of Psychology, Health and Society, said: "Realising you are an overweight individual is in itself likely to be quite stressful and make making healthy choices in your lifestyle more difficult. It is a tricky finding for public health intervention work.
"You would hope that making a person aware they are overweight would result in them being more likely to adopt a healthier lifestyle and lose some weight."
He added: "What is important is to tackle stigma in society. People with a heavier body weight have body image challenges. That is not surprising given the way we talk about weight as a society."
"But the way we talk about body weight and the way we portray overweight and obesity in society is something we can think about and reconsider. There are ways of encouraging people to make healthy changes to their lifestyle that don't portray adiposity as a terrible thing."
The research also involved Michael Daly from the University of Stirling and Jeffrey Hunger from the University of California.