Quote Originally Posted by CL0V3R View Post
Going to have to contest that not all diets work for all people. Especially considering she isn't even an adult yet. I honestly wouldn't suggest completely cutting out eating for 11 days.
Even not eating for a few days can make you feel ill. Not to mention the lack of energy she'll have.
In fact if you look into it you'll find things like so:
Water Fasting Side Effects | LIVESTRONG.COM
The Truth about "Starvation Mode"

Oh and let's not forget this super important fact.

Slower Metabolism
Your attempt to lose weight by consuming nothing but water can backfire in a big way. According to the Harvard Medical School Family Health Guide, any diet that is extremely deficient in calories causes the body's basal rate of metabolism to slow down. In other words, if your body believes that you're starving, it acts to preserve your chances of survival by slowing down the rate at which it burns energy. As a result, when you end your fast and begin eating again, you'll most likely start packing the pounds back on faster than ever before.

Normally I agree with you but this just seems like a terrible idea.
There are always things that work differently for different people, how ever if you do it all the right way, you can counter-act most of that stuff. But you are right on that one point that things work for different people.