A low carb diet, also known as a ketogenic or keto diet, is a diet in which you eat fewer than 50 grams of carbohydrates per day. When you consistently eat very few carbs, your body enters ketosis, a metabolic state in which your body uses ketones (derived from fat) as a source of energy instead of glucose (derived from carbs). When you cut carbs and eat more fat, your body will start to use the fat consumed as well as stored body fat as its main source of energy.

When eating low carb, most of your energy comes from fat. The few carbs you do eat are from wholesome sources like vegetables, nuts and berries. On a low carb diet, 70 to 75 percent of the calories you eat every day come from fat, 20 to 25 percent from protein and about 5 percent from carbohydrates.