Re: Does eating burnt food lower your calorie intake?

Hello Chad and thanks for the question.

As you stated in your question, Calories are determined by measuring the heat released when food undergoes combustion. Specifically, total calories are measured using a Bomb Calorimeter. Food Stuffs are placed in the calorimeter and burned to ash.

The net KJ are measured and used to determine the Calorie content (energy required to raise the temp of 1 g of water 1 degree Celsius). The human body works much in the same way [Except instead of burning food to ash, our bodies 'burn' food to carbon dioxide and water. -- Moderator].

Therefore, logic dictates that if a foodstuff is partially combusted prior to entering the Bomb Calorimeter or body then there will be less material (energy) remaining to undergo combustion and therefore fewer KJ/Calories will be produced, i.e. Total Calories – Calories lost as heat while cooking = Calories available for consumption.

The following USDA website will allow you to compare the compare calorie content of varies food items in their raw and cooked forms.

www.nal.usda.gov/fnic/cgi% 2Dbin/nut %5Fsearch.pl

For 1 slice of bread vs. 1 slice of toast the calories are the same. This is partially due to the high level of carbohydrates found in bread (harder bonds to break) but primarily the calorie count stays the same because of the superficial nature of toasting. If you were to cook the toast to an inedible state the calorie count should change. When comparing raw steak to cooked steak the calorie count decreases because of the extent to which heat applied. In all cases be sure that the raw and cooked items are comparable (same ingredients, trim, grade, cooking method, etc.) and that the cooking method does not introduce calories to the food as with frying.

Hope this helps,

Forrest