Which diets really work?

Best weight loss plans revealed. Photo: Getty Images

Diet trends seem to change quicker than Leo Dicaprio switches ladies. Paleo, Atkins, low-fat, meal replacement – it’s tough to know what plan will get you results.

A recent US study claims to have found the holy grail of weight loss: establishing which diets are most likely to deliver results and keep the inches off in the long term.

Jenny Craig and Weight Watchers showed the most evidence of long-term success, incorporating goal setting, self-monitoring and nutritional information.

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Researchers from John Hopkins University examined 4,200 studies to reveal the 11 most popular and effective weight loss plans. Doctors divided the diets into three categories, the first and top performers, is the lifestyle programs such as Jenny Craig.

The second group were very low kilojoule meal replacement diets (aka shake based plans). The results? Not so good. While dieters had lost weight at the four to six month mark, after 12 months the benefits were long gone.

Low carb, high fat diets such as Atkins made up the third group. These diets helped people keep it off at six and 12 months.

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Scientists say the approach “appears promising”. But there’s limited info on any clinical trials spanning beyond one year.

Jeanne Clark, professor of medicine says, “We want people to experience the health benefits of weight loss - lower blood pressure, cholesterol and blood sugar, and lower risk of developing diseases like diabetes.

“Those benefits are long-term goals - so losing weight for three months, then regaining it, has limited health benefits. That’s why it’s important to have studies that look at weight loss at 12 months and beyond.”

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The findings, published in The Annals of Internal Medicine, come with a call for more rigorous testing of online programs over longer periods, so what works and what doesn’t be can be better judged.

What’s worth paying for then? A plan you can stick to for at least a calendar year fancy claims or names aside.

We rate: a healthy lifestyle.

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