But new research has suggested it doesn't really matter which diet you go for.
According to a study published in the Journal of the American Medical Association, all diets have similar results and people should simply pick the one they find the easiest to stick to.
A Canadian team of obesity experts analysed data from 48 separate studies to reach this conclusion.
The scientists, based at McMaster University in Ontario and the Hospital for Sick Children Research Institute in Toronto, analysed data from 7,286 dieters who were classed as being "overweight".
Their research showed that after 12 months, people on low carbohydrate and low fat diets both lost the same amount of weight on average (7.3kg/16lb), suggesting that neither diet type is more effective than the other.
The dieters involved in the study were trying out various plans, including Akins, Jenny Craig, South Beach and Rosemary Conley.
The study authors concluded: "Our findings should be reassuring to clinicians and the public that there is no need for a one-size-fits-all approach to dieting because many different diets appear to offer considerable weight loss benefits.
"Significant weight loss was observed with any low-carbohydrate or low-fat diet. This supports the practice of recommending any diet that a patient will adhere to in order to lose weight."