One of the first things I look at when someone complains that they are not losing weight or asks for exercise advice is how much they are eating. It seems that of the many misconceptions running rampant out there that starving yourself to lose weight is high on many people's lists. Listen: starving yourself DOES NOT work. It just doesn't. When people try to put themselves into a fake starvation mode, their bodies hold on to every ounce that they possibly can. What people end up losing is muscle, connective tissue, and organ tissue. How could anyone think this is good or healthy?
What you want to lose is fat. Sure, most people will end up losing a litte bit of muscle when they go on a diet. However, I have found that on the Atkins plan I lose mostly fat. When I added weight lifting back into my schedule, I put on 5 pounds of lean muscle mass in just over a month. By taking your measurements and plugging them into a site such as this one: http://www.scientificpsychic.com/fitness/diet.html you can track the important things like lean muscle mass and body fat percentage. In 2 1/2 months on Atkins I lost 21 pounds of fat, gained 5 pounds of lean muscle mass, lost over 10% body fat, and over 19 inches! No scale will tell you all that. Incidentally, the scale says I've lost 16 pounds and 6% body fat. It is wrong.
So how do you lose all this fat? You have to get enough calories. For women, this means 1500 minimum a day and more if you are exercising. I am often between 1700-1900 calories, but recently bumped up to 2,000 and am still losing. Men can get a minimum of 1800 and 2000-2200 when they start exercising. I know plenty of weight lifters who push closer to the 3000 calorie level, but that's something you should build up to and evaluate over time.
Under no circumstance should you eat under 1200 calories a day. This does all kinds of nasty things to your body. Unfortunately, many women eat under 1,000 calories a day, and have support groups to congratulate themselves for starving. If you listen to them and read their posts, however, they all complain about not losing weight, feeling tired, and many of them feeling depressed. If they would only eat more healthy food not only would they see the weight start to drop off, they would have energy and feel great!
If you are eating less than 1500 calories a day and aren't losing weight, try eating more. After all, what you are doing isn't working. So what do you have to lose?