Nutrition & Food
Basic

Food Energy (Atwater)

Total food energy in kilocalories from its macronutrients using the Atwater factors.

Formula

E=4P+4C+9F+7AE = 4P + 4C + 9F + 7A

Variables

PProtein (g)
CCarbohydrate (g)
FFat (g)
AAlcohol (g)

Example

20g P, 30g C, 10g F ⇒ 4·20+4·30+9·10 = 290 kcal

Did You Know?

Wilbur Atwater burned foods in a bomb calorimeter in the 1890s to derive the 4-4-9 factors still printed on every food label today.

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