A 300 pound, 5 foot, ten inch, 25 year old man burns about 2450 calories a day to MAINTAIN his weight. You have to consider the person's height, but if you are around that height it is a good estimate. You need to eat 3500 calories less a week to lose one pound of fat. If you eat 1700 calories instead of the 2450 you would need to maintain, you would end up with a calorie deficit of 5250. You end up losing about a pound and a half a week without any exercise - if you increase exercise you can burn more. It is best to lose two pounds a week if you want to keep it off, but at 300 pounds, it is pretty safe to lose 3 pounds a week until at least half of your weight loss. Don't be surprised if you lose a little more initially but it will start falling at 1.5 pounds without exercise. Whatever you do...don't cut out too many calories or your body will think it is starving. When you lose more weight, remember you will need to recalculate, but I would stick to this for three months.
