Thermic Effect of Food (TEF)

The thermic effect of food, or TEF, is the energy your body burns just to digest, absorb and store the food you eat. Protein has the highest thermic effect, meaning a higher-protein meal uses more energy to process. It is a small but real part of your daily calorie burn.

The thermic effect of food, also called diet-induced thermogenesis, is the increase in energy expenditure above basal levels after eating, accounting for roughly 10 percent of total daily energy expenditure. It varies by macronutrient: protein elicits the greatest response at 20 to 30 percent, followed by carbohydrate at 5 to 10 percent and fat at 0 to 3 percent, and is influenced by meal size and composition.

TEF helps explain why higher-protein eating patterns can modestly support weight management. Dr Joseph Wang uses this principle alongside others when personalising nutrition advice.