Thermic Effect of Food Calculator

About this calculator

This calculator computes the thermic effect of food (TEF) — also called diet-induced thermogenesis — the energy your body spends digesting, absorbing and metabolizing what you eat, calculated as a percentage of calories consumed. It varies by macronutrient: protein has by far the highest TEF (about 20–30% of its calories), carbohydrates around 5–10%, and fat only about 0–3%, so a mixed diet averages out to roughly 10%.

TEF is one of the three components of total daily energy expenditure alongside basal metabolic rate and physical activity, and it's a key reason nutritionists recommend higher-protein diets for weight management — not only does protein feel more satiating, it also burns more calories just being processed.