But, new research appears to prove that staying slim is largely down to genetics. Thin people generally owe their body type to a “skinny gene”, according to a new study published in PLOS Genetics journal.
A University of Cambridge academic, who lead the study, has called for people to be “less judgemental” about weight, in light of the findings.
“This research shows for the first time that healthy thin people are generally thin because they have a lower burden of genes that increase a person’s chances of being overweight and not because they are morally superior, as some people like to suggest,” said researcher Professor Sadaaf Farooqi.
“It’s easy to rush to judgement and criticise people for their weight but science shows that things are far more complex.
She added: “We have far less control over our weight than we might wish to think.”
Farooqi’s words call out the practice of body shaming, where people are stigmatised for their body shape or size.
Why “skinny” people have a genetic advantage
The investigation looked at 1,600 healthy, very slim people with a body mass index of less than 18 – which is generally considered underweight by the NHS, who deem 18.5 to 24.9 as the “healthy” range. Lifestyle questionnaires ruled out the possibility of eating disorders in these individuals.
These individuals were compared to 2,000 severely obese people and 10,400 people of a normal weight.
The “skinny” subjects were found to have fewer genes linked to obesity, as well as certain genes associated with thinness.
Meanwhile, on average the severely obese individuals were more likely to possess a gene set linked to obesity.
Another factor linked to obesity in the UK is a lack of understanding around portion sizes.
A new survey by the British Nutrition Foundation (BNF) has revealed that many Brits don’t know what constitutes a healthy portion size. The ‘Find Your Balance’ guide uses simple hand and spoon measurements to help people to estimate appropriate portions when both cooking and serving food.
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