Vance Kelly

Diets are methods of controlling energy intake through ingestion of food. A universally accepted rate of food intake to lose 1-2 pounds a week is around a daily intake of 1350 calories. Faster weight loss requires decreasing this value or increasing physical activity and/or metabolic processes. Physical activity requires expending a certain amount of energy or calories to do. Thus, crash diets that work increases the difference between intake and expense.