The grapefruit diet is based on the premise that the fruit has fat burning properties. As our diet plan review explains, it's been dismissed as another 'fad' eating programme. The grapefruit diet lasts 12 days but if an individual wants to continue longer, they must take at least two days off before doing so. There is no scientific evidence that the fruit can burn fat, but it has very low calorific content, so the grapefruit diet can bring about weight loss. Whether it's sustainable is another matter. The grapefruit diet has been around since the 1930s in one form or another but one constant remains, you have to eat the fruit or drink its juice before you eat.

The diet meal plans and recipes of the programme are strict. Breakfast, lunch and dinner are accompanied by the fruit and it's also recommended to drink eight glasses of water a day, along with unlimited cups of black coffee. The programme does not allow most complex carbohydrates, and doesn't allow for snacking in between meals. However, the consumption of vegetables is encouraged and you are allowed to prepare them in generous amounts of butter.

There are many critics of the programme who claim it is an unhealthy and a medically unsound means to lose weight. Like many starvation diets, the weight that is lost on the diet is quickly put back on again, with the possibility of even more weight coming back on because of the metabolism slowing down. However, new evidence may be emerging that a diet rich in grapefruit may have other hidden health benefits.