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However, I did find that low-calorie whole foods do in fact require more energy to be digested than other highly processed calorie-dense foods.
The calories used to break down a food item is known as it's "Thermic Effect", i.e. "the amount of energy used by your body to digest, absorb, and dispose of the food you ingest."(1) The thermic effect of foods can vary anywhere from 3% of total calories for fats to about 20% for many vegetables and 30% for most proteins.(2) That is, eating 200 calories from fat only takes 6 calories to digest while digesting 200 calories from protein would require 60 calories. In this way some foods do have lower net calories once they are processed by your body. By making foods like fibrous fruits and vegetables as well as lean protein a part of your diet it's certainly possible to stay satisfied while reducing your overall caloric intake (an essential aspect of successful dieting).
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Sources:
1. http://www.livestrong.com
2. http://worldfitnessnetwork.com
3. http://theoatmeal.com/comics/ie
4. Reinagel, Monica. How to Win at Losing: 10 Diet Myths That Keep You from Succeeding. New York: St.Martin's Griffin, n.d. Print.