Everyone's caloric needs are different, depending on bone structure, age, activity level. The number of calories must be calculated for each individual. Saying everyone should drop to 1000 calories/day is like saying everyone should be able to walk 50 miles/day.
One pound equals 3500 calories, therefore, if you want to lose one pound/week, you would need to drop your calories by 500 calories/day (500 calories X 7 days = 3500 or 1 lb). Most of us find it easier to drop 250 calories/day, and use up an extra 250 to make up the 500 calories/day. Safe weight loss is 1-2 pounds/week.
You need to do some working outs - the best place to start is:
Your BMR (Basal Metabolic Rate) is the estimated minimum level of energy required to sustain the body's vital functions when at rest. The Harris-Benedict formula is used to calculate the BMR (Basal Metabolic Rate).
This is how many calories your body needs when at reast to maintain its current weight.
It varies from person to person. But this calculator gives you an idea.
http://www.fitwatch.com/qkcalc/bmr.html
My BMR is 1641 - so I need to eat 1641 calories to fuel my body when it is at rest. Anything over that needs to be burned off to avoid weight gain..... if I eat less than that my body will slow down its metabolism to conserve fat stores, to convert carbs to sugar for energy and I will slow down my weight loss....
Ideally for slow and sustained and steady weight loss eat appropriate for your BMR and move more - not always about the gym, or planned exercise its about suing your body more often in day to day things, walk a little more, when doing laundry, take one or two items a time upstairs so instead of one up and down you do 10 or 11... only a few minutes more but a good calorie burning oppertunity.
You should decrease you calorie intake by about 500-600 a day to lose weight. At the very minimum 1200, but that is VERY LOW. I say around 1400-1600. The other poster said 1000 calories and that is completely ridicilous. You will not lose because your body will enter what is called...."STARVATION MODE" and store all the fat you have. That is very unhealthy. Just look up any site online you will loads of info.
Good luck!
Hey you need to have only 1000 calories per day.