Celebrity Diets

The theory is if carbohydrates are restricted the body turns to fat to burn as its main energy source, resulting in a rapid and dramatic weight loss.

Baby food dieters replace two meals a day with a pot of pureed baby food and then fill up on one healthy adult meal. As the average baby food jar contains about 80 calories, it's a dramatic calorie cutting diet.

A cup of coffee before a gym workout could help you burn more fat. Researchers at the Australian Institute of Sport found caffeine triggers the muscles to use energy from fat sources rather than carbohydrate. But even if you are not a gym bunny, daily caffeine fixes can help raise your metabolism, and the stimulant acts as a mild appetite suppressant.

The rules are you eat cabbage soup for seven days, which fills you up, along with fruit, vegetables, fish and chicken. Follow closely and lose up to 10lb in a week.

The detox plan involves avoiding refined sugary and "toxic" foods such as wheat, potatoes, dairy produce, citrus fruits, red meat and alcohol.

Fruit juices Fruit and vegetables never go out of fashion for stars eager to keep in shape and juices or smoothies are an easy way to get your antioxidant fix.

Foods are ranked on a scale from zero to 100 based on how much they affect blood sugar. Low-GI foods help stabilise blood-sugar levels so you don’t go through cycles of sugar highs and lows. You’ll feel fuller for longer and less likely to snack.

“Six small meals can suit some people really well,” says dietitian Nigel Denby. “It works by keeping your blood sugars steady so you are less tempted to snack. Psychologically as you’re not going too long between eating, you don’t feel deprived. Remember, though, it is LITTLE and often, so the portion has to be small.”

The regime allows five meals a day but only from certain food groups. No booze, bread, starchy carbs, dairy, fruit and saturated fats.

Also called the Caveman Diet, it harks back to the Stone Age when cavemen ate just one meal a day. For the caveman diet, your main meal of the day should be a balance of protein, carbs and vegetables in the evening.

Eating the same sized meal as your other half? Then you need to look at your portion sizes.

The clue is in the name - its all about raw food. A daily dietshould be made up of two thirds raw vegetables and one third meat (not pork), fish and dairy products.

All foods are given a WeightWatchers' points value based on their calorie and saturated-fat content. You can eat any foods you like as long as you don't go over your daily points allowance (which is based on your age, weight and activity levels). Support and encouragement comes from weekly group meetings, where members are weighed.