Metabolic Rates and the Energy Cost of Eating

A lower level of lean body mass or body weight correlates with a reduced resting metabolic rate and energy expenditure, highlighting the importance of metabolic adaptation. Total daily energy expenditure comprises three components: resting metabolic rate, diet-induced energy expenditure (thermic effect of food), and activity-related energy expenditure. Diet-induced energy expenditure accounts for the energy consumed in the processes following food intake, spiking by 10-15% for three to four hours post-meal, especially after high-calorie, protein-rich, or fiber-rich meals. Factors such as age, body composition, physical activity, meal size, composition, frequency, and timing can further influence the thermic effect of food.