Lover's Cookbook - 100+ perfect and wonderful recipes next to the your love: Food provides us with essential energy to keep our bodies functioning. When you take a bite of food your body jumps into action. The carbohydrates in food are converted into glucose which is used as energy. However, when the consumption of carbohydrates is significantly reduced, the body starts to use fat for energy instead. This process is called ketosis. Once your body goes into ketosis, you begin to burn up the stored fats as well as the fats you ingest, and this in turn leads to significant weight loss.