How much weight can you lose if you do not eat for a day?

Depending on your eating habits this can actually cause you to gain weight. You will retain water, and burn muscle instead of fat if you're not eating healthy. All depending on the person, you CAN loose not even a pong just a couple ounces but depending on how much you reguarly eat a day, you can end up gaining weight if you a lot each day. Or even, on some people it won't effect at all.