An obesity expert says mocking the overweight 'should be illegal'. Stock photo

Poking fun at fat people should be treated as seriously as racism and sexism, researchers have said.

Obesity expert Dr Sarah Jackson said that the law should protect against weight discrimination, in the same way at it prohibits singling out people based on their age, gender or race.

Dr Jackson, of University College London, spoke out after conducting two studies into the physical and psychological effects of fattism.

Her latest study, of more than 5,000 British adults found that those who were made to feel ashamed of their size suffered more symptoms of depression.

They also had a lower quality of life than those who didn’t feel victimised.

Examples of fattism included being treated disrespectfully, including being the butt of jokes, receiving poorer services in shops, restaurants, hospitals and doctors’ surgeries, being threatened and being assumed to be stupid.

She previously showed shaming fat people into losing weight is counterproductive.

Far from shocking people into slimming, it actually leads to them piling on the pounds.

It is thought fattism drives those who are already sensitive about their weight to comfort eat. Fear of ridicule may also mean they avoid exercise.

With two-thirds of British women overweight or obese, jibes, taunts and simple thoughtlessness could be having a huge effect on the nation’s mental and psychological health.

Dr Sarah Jackson, the lead author of both studies, said that people may believe that weight discrimination is socially acceptable because unlike ageism, sexism and racism, it is not covered by law.

She said: ‘In the United Kingdom, the Equality Act 2010 legally protects individuals from discrimination on the basis of age, sex, race, disability, religion or beliefs, sexual orientation, marital status, pregnancy, or gender reassignment; making it clear that discriminatory behaviour of this nature is not to be accepted.

‘However, our results indicate that discriminatory experiences contribute to poorer psychological wellbeing in individuals with obesity, but there are currently no laws prohibiting weight discrimination.

‘This might send the message to people that weight discrimination is socially acceptable.

Dr Sarah Jackson said that the law should protect against weight discrimination, in the same way at it prohibits singling out people based on their age, gender or race. Stock photo

‘If weight was a protected category it might help to reduce the prevalence of weight-related discrimination and thereby improve quality of life and wellbeing for a significant proportion of obese individuals.’

Researcher Professor Jane Wardle said: ‘Combined with our previous work showing that weight discrimination does not encourage weight loss, we can see that weight discrimination is part of the obesity problem and not the solution.

‘Weight bias has been documented not only among the general public but also among health professionals; and many obese patients report being treated disrespectfully by doctors because of their weight.