because virtually eliminating carbs makes it really hard for your body to store water, so it's important to drink lots of water on this diet. Then it became the Atkins diet. It works for the short term--weight loss is quick and extreme--but it's pretty much impossible to sustain over time, and it's the maintenance of weight loss that's the real problem with diet programs. And you will have dry mouth and bad breath and constipation, especially if you don't drink enough water.
I lost 85 pounds by starting from the point of what I like to eat for each meal, then tailoring portions to make it fit into a 1200 calorie diet. So I was eating things that I like for every meal, in "normal" portions, no snacking and I never did drink soft drinks, and it was easy to stay on this eating program for the rest of my life so far. My weight loss was quick and extreme at first, and now, six years later (haven't gained a pound back) I'm still eating pretty much the same as I was when I started out, and my weight has stabilized. When I get tired of something, I replace it with something else I like to eat, making sure that my portion is what is "normal"--check the package of processed foods, like breakfast cereals, and a generic calorie guide for everything else--to keep it within the 1200 calorie limit.
I lead a pretty sedentary life, so if you're active physically, you'll want to check a chart to find out how many calories you should be consuming at your "normal" weight.