Enter the characters you see below Sorry, we just need to make sure you’re not a robot. The energy contents of a complex dish or meal can be approximated by adding the energy contents of its components. The first determinations of the energy content of food were made by burning a dried sample in a bomb calorimeter and measuring the temperature change in the water surrounding the apparatus, a method known as direct calorimetry. Calories per g of protein system was later improved by Annabel Merrill and Bernice Watt of the USDA, who derived a system whereby specific calorie conversion factors for different foods were proposed.
Carbohydrates, fats, and proteins typically comprise ninety percent of the dry weight of food. Other minor components of the human diet that contribute to its energy content are organic acids such as citric and tartaric, and polyols such as glycerol, xylitol, inositol, and sorbitol. Some nutrients have regulatory roles affected by cell signaling, in addition to providing energy for the body. For example, leucine plays an important role in the regulation of protein metabolism and suppresses an individual’s appetite. Some polyols, like erythritol, are not digested and should be excluded from the count.
