A UK study of nearly 3,000 adults over four years found those who had experienced weight discrimination gained more weight than those who did not.
Researchers believe the discrimination-related weight gain was caused by comfort eating.
Published in the journal Obesity, the study looked at data from adults aged 50 and over who ranged from normal weight to obese.
The participants were asked if they had experienced day-to-day discrimination that they perceived to be connected to their weight.
Examples of the types of discrimination they endured included being treated disrespectfully, receiving poor service and being harassed in public.
One in 20 reported weight discrimination and, for the morbidly obese group, discrimination was as high as one in three.
Participants in all weight ranges who experienced negative attitudes toward their weight gained 1kg on average over the four year period.
Those who did not experience such discrimination typically lost 1kg on average over the trial period.
The researchers say these findings suggest blaming and shaming is counter-productive.
As a result of the study health professionals have been advised to be more supportive of those who need to lose weight.
“There is no justification for discriminating against people because of their weight,” said Dr Sarah Jackson, the study’s lead author.
“Previous studies have found that people who experience discrimination report comfort eating.”
“Stress responses to discrimination can increase appetite, particularly for unhealthy, energy-dense food.”
“Weight discrimination has also been shown to make people feel less confident about taking part in physical activity, so they tend to avoid it.”