Sticking to a diet is key to shedding the pounds as all branded weight loss plans reap similar results, researchers have found.

Canadian scientists said the difference in weight loss between diets is so small that people should simply choose the diet they find the least challenging.

Scientists at McMaster University in Ontario and the Hospital for Sick Children Research Institute in Toronto analysed 48 trials including data from 7,286 overweight dieters.

They looked at dieters’ weight loss at six and 12 months, to see if there was any benefits to particular diets.

After 12 months people on low carbohydrate and low diets lost similar amounts of weight, an average of 7.3kg

Eva Mendes (pictured left), who weighs a tiny 57kg follows the low fat South Beach diet, while Jennifer Aniston (pictured right) is a fan of the high protein Atkins diet

Jessica Simpson follows the Weight Watchers diet, but also went on a vegan diet in the two weeks running up to her wedding to Eric Johnson

The study, published in the Journal of American Medical Association, found that after 12 months, people on low carbohydrate and low fat diets lost a similar amount of weight, an average of 7.3kg.

Those on low carbohydrate diets had lost slightly more weight at six months, but by 12 months the difference was obsolete.

The researchers did find that diets with behavioural support and exercise enhance weight loss.

At six months, diets with behavioural support enhanced weight loss by about 3kg, while exercise was significant at 12 months, improving weight loss by about 2kg.

The study concluded: ‘Significant weight loss was observed with any low-carbohydrate or low-fat diet. Weight loss differences between individual named diets were small.

‘This supports the practice of recommending any diet that a patient will adhere to in order to lose weight.’