You can eat, drink, and lose weight, it's not a myth. What is far more important is what you eat and drink and how you eat and drink it. The goal here is to boost your metabolism so that what you eat, you burn.
If you go on a crash diet, of course you will be on a fat burning diet. Trouble is, fat is not all you will burn. As well as fat burning, you will burn muscle and lean tissue. You will burn your energy reserves. Not really the most fun you can have while standing up. Don't do it to yourself.