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Not so. The caloric requirements of women vary, just as men's do. I know quite a few women who are 5'7" to 5'9". While 1100 calories a day may be doable for a woman of 5'1" to 5'4" or so, taller women need more calories, and the requirements of women with fast metabolisms vary as well, not to mention those who run, lift weights or do other forms of exercise.
I first heard that two years ago at a lecture about nutrition, and the audience mostly screamed and booed at the guy. When we calmed down, he went through it.
A woman about 5'6" tall only needs 1100 calories. She can add to that for exercise, but don't be too generous. I add less than 200 calories a day for three miles of walking.
Here's the trick. The food has to be high nutrition. I eat boiled or steamed veggies, plain meats, fruits with no sugar added, almond milk, some whole grains. No high-calorie drink concoctions or soda. No transfat. With lots of those veggies, the nutritional value piles up, it's filling, and it's low in calories, "efficient food". FWIW, I was born 10% overweight and battled weight my whole life. Now I'm a just about perfect weight for 5'7" and never hungry.