For some people it is simply a case of being "cruel to be kind". But contrary to the belief that calling people fat will motivate them to lose weight, so-called "fat shaming" can lead them to eat more.
A new study warns that shaming those who are overweight fails to help them slim and can cause them to put on more weight as they resort to "comfort eating".
In a study of 2944 British adults over four years, those who reported experiencing day-to-day "weight discrimination" gained more weight than those who did not, and experts warned that such people were often treated disrespectfully by their own doctors.
Study author Dr Sarah Jackson of University College London said much of the problem was the use of the "language of blame".
"There are lots of different causes of obesity but a lot of blame seems to be put on individuals and lack of will power," she said.
Tam Fry, of the UK National Obesity Forum, welcomed the study: "Shaming is totally wrong... be understanding and talk to the people and not at them."
The research, published in the journal Obesity, found that people who experienced weight discrimination gained an average of 0.95kg, whereas those who did not lost 0.71kg, a difference of 1.66kg.
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