Atwater system

Definition

The Atwater system is a method used to estimate the metabolizable energy content of foods by assigning specific caloric values to macronutrients: carbohydrates, proteins, and fats. It is widely used in nutrition science to determine the energy available from food consumption.

5 Must Know Facts For Your Next Test

1. The Atwater system assigns 4 kcal/g for carbohydrates, 4 kcal/g for proteins, and 9 kcal/g for fats.
2. It helps in calculating the total caloric content of food by summing up the contributions of each macronutrient.
3. Developed by Wilbur Olin Atwater in the late 19th century, it is still a foundational concept in nutritional science today.
4. The system assumes that all macronutrients are fully digested and absorbed, which may not always be accurate.
5. Alcohol is also considered in the Atwater system with an assigned value of 7 kcal/g.

Review Questions

Related terms

Calorimetry:

A technique used to measure the amount of heat involved in chemical reactions or physical changes.

Metabolizable Energy: The portion of food energy that is available for metabolic processes after losses in feces and urine are accounted for.

Macronutrients: Nutrients required in large amounts that provide energy; includes carbohydrates, proteins, and fats.