If i ate cottage cheese every day & drank water every day, will i lose weight fast?

It depends...: It depends on what else you eat and how much cottage cheese you eat- if you eat only a little cottage cheese & nothing else but water, you would lose weight, but I do not recommend this, as it would not provide complete nutrition. You can have salads/vegetables for better nutrition & still lose weight. And please choose organic cottage cheese. But the best diet is one that you can follow for years.

Yes: Loosing weight fast is dangerous can hurt major organs like heart and intestine - safer to do steady weight loss that is balanced.