Scientists from the north-east have found proof that eating fat is the only cause of weight gain.
A team from Aberdeen University published the findings of its pioneering research, which was conducted in partnership with researchers in China.
They fed a combination of 30 different diets to groups of mice, each varying in fat, sugar and protein contents for three months – the equivalent of nine years in humans.
During this time they made over 100,000 measurements of their weight changes and measured their body fat using a tiny MRI machine.
Professor John Speakman, who led the study, said: “The result of this enormous study was unequivocal. The only thing that made the mice get fat was eating more fat in their diets.”
The research revealed that increasing carbohydrates had no effect on their weight, while diets combining sugar with fat were no more effective than fat on its own.
Professor Speakman said: “These effects of dietary fat seemed to be because uniquely fat in the diet stimulated the reward centres in the brain, stimulating greater intake.”
He added: “A clear limitation of this study is that it is based on mice rather than humans.
“However, mice have lots of similarities to humans in their physiology and metabolism and we are never going to do studies where the diets of humans are controlled in the same way for such long periods.
“So the evidence it provides is a good clue to what the effects of different diets are likely to be in humans.”