What is the thermic effect of food?

The term "thermic effect of food" is used to describe the energy expended by our bodies in order to eat and process (digest, transport, metabolize and store) food. We "expend energy" by burning calories.

Processing protein requires the greatest amount of energy, with estimates ranging as high as 30%. Dietary fat, on the other hand, is so easily processed and turned into body fat that there is little thermic effect, perhaps only 2 or 3%. The amount of energy required to process carbohydrates falls between that of protein and fat.

A figure of 10% is generally used to account for the thermic effect. This would mean that if you wanted to replace 500 calories burned through activity, you would eat around 110% or 550 calories.

Most people are either unaware of the thermic effect of food or choose to ignore it, making weight loss seem just a little easier.