I've had some questions asked of me about this diet, so I thought I'd post some of my answers in case anyone else is wondering the same thing. If you've got more questions, please feel free to ask and I'll try to answer them as best I can based on my research.
Q: Do you really eat 500 calories a day on this diet?
A: Yes, you only EAT 500 calories a day. But the HCG unlocks the abnormal fat stores, which usually go untouched by dieting because the body first uses normal fat stores when there is a lack of calorie intake, so up to another 2000 calories a day are released into the blood stream from that fat. The reason behind it is that when a woman is pregnant and building a baby, her body needs to make sure that energy is pulled from stored fat, not from the muscle or healthy fat tissue that is becoming the baby. That's the whole key to using HCG. It is nature's way of making sure a woman can build a healthy baby. And I for one can vouch for the fact that my metabolism is awesome when I'm pregnant. I only gained 17 and 18 lbs with my two kids even though I ate like a fiend the entire time.
Q: Is it healthy to eat 500 calories?
A: Normally no. Normally that's called starvation and not only is it not good for you (because it forces the body to get energy from muscle tissue) but it also jacks up your metabolism. That's where the HCG intake is crucial. Like I said above, extra calories are being released into the blood stream as those resistant fat stores are broken down. So a person doesn't starve. in fact, their body is getting plenty of energy. Therefore not only are the fat stores broken down, the metabolism never goes into starvation mode.
Q: Can you keep the weight off?
A: Well, if you follow the whole diet--minimum 23 days on HCG + 21 days of maintanance diet (reintroducing fats and sugars slowly), you should have reset your hypothalamus to use the abnormal fat stores more readily. But like any post-diet, it depends on what the individual person does. If they go back to eating a lot and not exercising, yes, they will gain it back. If they maintain a reasonable diet with moderate exercise, they shouldn't. This diet requires people to continue to monitor weight every day for a while after the diet ends, and if weight goes up more than 2 lbs, there is a temporary food regimen the person can use to stop the weight gain. But again, it's all about what you do after the diet is done. The diet is not meant to be one you live on for the rest of your life. It's meant to get the weight off and then you have to be sensible to keep your weight. I think this is true of any diet or even gastric bypass: If you lose the weight, you have to eat and exercise in a way that will allow you to keep it off. Of course, this is all theory for now. We will see what happens to me once I go off! I have been pretty good about staying within 2-3 lbs of my current weight for the last 2 years, so I feel pretty confident that once I go off I can stay there. I'll keep you posted!
4) As for whether it is a fad diet that will later turn out to be dangerous, I highly doubt it. First of all, this diet has been around since the 1950's or 1960's. It has been used by obesity clinics on thousands and thousands of patients on several continents. And the amount of HCG used for the diet is 1/100th of what a pregnant woman's body produces in a day. (Pregnant woman 10,000 iu's of HCG per day, this diet 125-175 iu's). So I can't imagine that small amount could be unhealthy. I read through a lot of websites before starting this diet, and I couldn't find any sites that claimed any health dangers from it. And it's been around so long, that you'd think by now something would have come up if it were dangerous.
I hope that helped. I'm not an expert; I've just started. But I did have a lot of reservations about this diet and tried to research a lot before starting it. I really hope it works because I just didn't have much hope of ever losing these last 15 lbs without some help.