Is this the end of the yo-yo diet?

Women who are more susceptible to gaining weight after dieting may possess a key type of protein in their blood, according to a new study.

Jealous of those friends that always stay skinny, even when they're not dieting? Well, doctors may be able to explain why. Women whose weight continues to yo-yo may possess a certain type of protein in their blood.

The protein angiotensin-converting enzyme has been strongly linked to a woman’s weight and how she retains her shape after dieting.

Soon, a simple blood test will be able to tell you whether you're more susceptible to increased weight gain after stopping your diet.

‘Despite what we might think, people are not bad at losing weight,' where they really struggle is in keeping it off,' says Susan Jebb, from the Medical Research Council’s nutrition centre in Cambridge, who stressed that much more work needs to be done before a blood test for dieters is developed.

‘Yo-yo dieting is psychologically upsetting for people and repeated cycles which feel like failure breed a lack of self-confidence,’ she added.

Researchers fromeight European countries, including the UK, analysed the blood of 96 dieters who had already lost weight. Half successfully kept it off, or lost even more. But the others regained the weight.

Those women who later kept the pounds off tended to experience large drops in the levels of the enzyme.

At the moment, it's unclear how the protein affects dieters, but it is believed to interfere with the hormones that control how full we feel and by making the body store extra fat and water.

‘It is very intriguing,' said James Stubbs, an obesity doctor at Slimming World. 'Maintenance of weight loss is absolutely critical to success.'

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