What is it?

Please remember grapefruit juice can interfere with the absorption of medicines and/or react with them, please seek out medical advice if you wish to try this diet.

The grapefruit diet is an interesting one, because nobody is sure where it came from, the same as the cabbage soup diet, but also nobody is sure what you are supposed to do on it either!

The idea behind the diet is that grapefruits have some sort of enzyme in them which when eaten with protein encourages fat loss. That combined with a drop in your daily calorie intake to as low as 800 – 1000 calories is supposed to give 10lbs of weight loss in just 12 days.

While there is no definite scientific evidence to back up this claim then there was a study done in 2006 which was funded by the Florida Department of Citrus. This showed by having grapefruit with every meal then over the course of 12 weeks the participants lost an average of 3.5lbs, while those who didn’t eat any lost less than a pound. That was with a normal calorie intake and slightly increased levels of physical activity, not the super low calorie intake suggested for this diet.

Based on the results of the study then they are looking into the possibility that the juice helps your body regulate insulin levels.

Grapefruits are a low calorie, low GI food (a rating of 25) which are high in fiber, vitamins A & C and contain various other vitamins and minerals, so they are not a bad food to eat, but they will definitely drive you crazy if you have to eat half of one or drink the juice before every meal!

There may be some truth that eating a low GI fruit before your meal will curb your appetite and make you eat less or cope better with the lack of food that often accompanies the diet, but in reality the weight you lose will be from the severe restrictions of calories not from eating the grapefruit.

Plus on that note then the versions of the grapefruit diet which get you to eat just 800 – 1000 calories are dangerously low on calories for most people, if you follow that for any length of time then your body will start to go into starvation mode and conserve as much fat and energy as possible. Your body will also start to break down your muscles to fuel itself so any weight loss will bea combination of fat, muscle and water loss rather than true fat loss.

I tried eating grapefruit with every meal and while it did not make me any less hungry for the actual meal (eaten about 20 – 30 minutes before) then it did make me feel a lot less hungry in between meals so making me less likely to snack, this may be due to the effect on insulin levels which is being investigated.

So if you want to eat grapefruit before a big meal then by all means do, but don’t lower your calories to the incredibly low levels some people suggest, and always consult a doctor before making changes to your diet (especially as grapefruit can interfere with medications!).

If you want a simpler diet to follow then check out our Eat Stop Eat review