A diet containing fewer than 800 calories of energy per day. Adherence to a VLCD results in rapid weight loss and must be monitored medically.
A commercially available diet in which caloric intake may be from 400 to 800 kcal/day. The very low calorie diet is usually in the form of a powdered supplement that is taken 3 to 5 times a day with large amounts of water. This type of diet can be effective, but the long-range efficacy in maintaining the weight loss may be discouraging. Vitamins and minerals are typically added to this eating plan because the small number of macronutrients consumed are inadequate to supply daily needs.