The Atkins Diet works on the principle that limiting the body's intake of carbohydrates forces it to burn fat. It begins by cutting out almost all carbohydrates. After the initial two weeks, the dieter begins gradually adding healthy carbohydrates back in until he reaches a maintenance level.
The Atkins Diet does not require counting calories so long as portion sizes are reasonable. It does require dieters to keep track of net carbohydrates that they consume. Net carbohydrates are the total grams of carbohydrate minus the grams of fiber a food contains.
During the induction phase, a dieter limits net carbohydrates to 20 grams daily, mostly from non-starchy vegetables. After two weeks, the dieter moves to the ongoing weight loss or balancing phase. During this phase, he adds 5 grams of net carbohydrates weekly until he finds the level at which weight loss stops. He then cuts back net carbohydrates by 5 grams to continue weight loss.
As the second phase continues, the dieter gradually adds in nutritious carbohydrates from legumes, berries, nuts and seeds. At about 10 pounds from the goal weight, the third phase, pre-maintenance, begins. In this phase, the dieter adds in fruits, whole grains and starchy vegetables to increase net carbohydrate consumption by about 10 grams per week, cutting back if weight loss stops. The fourth phase, maintenance, begins when the dieter reaches his target weight and lasts throughout life. At this point, the dieter can eat the amount of carbohydrate that allows him to maintain a stable weight.