I never went on the Grapefruit Diet, but I have limited my calorie intake to around 800 - 1000 per day. Drinking plenty of water, I lost around 85 lbs in about 6 months. You don't have to go on any kind of fad diet to lose weight and you don't have to avoid certain foods. Eat what you like, just keep things in moderation. The body burns calories the same whether they come from vegetables or snack cakes - the body doesn't know the difference. Just don't overdo it.

I had a friend do it successfully but she did it under a doctor's care. 😗😏 I have been advised by my doctor NOT to do it.

They will gain any weight loss back.

I think people have used this as a quick short-term weight loss, but not prolonged, Grapefruit also has an enzyme in it that can react to certain medications. Best way to loss weight is to have a balanced diet, any restrictive diet usually leads to thoughts of deprivation, so then you eat to feel better, then you feel guilty and it becomes yo-yo dieting, which is never good for the body. If you want to lose weight it has to be a lifestyle choice so you stick at it, not deprivation. Sugar in of itself can be addictive. Best to find an activity that you enjoy doing, I hate the gym, I'd rather be out in nature talking a brisk walk, or dance in my home. Need to look at food differently, see it as fuel rather than something to fix feelings. Food can have an emotional component, some people mistake anxiety for hunger and this leads to overeating, as they try to push their feelings down with food, literally swallow them. So keeping a diary can be good, so that you acknowledge how you feel, and learn positive techniques to deal with difficult emotions. Just finding activities which you can absorb yourself in where you lose all thought of food is a good thing as well as this stops snacking out of boredom.