# Calorific values

**URL:** <https://boards.straightdope.com/t/calorific-values/641749>\
**Category:** Factual Questions\
**Created:** [November 21, 2012, 6:28pm UTC](https://boards.straightdope.com/t/calorific-values/641749 "2012-11-21T18:28:19Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![RogerDis](https://avatars.discourse-cdn.com/v4/letter/r/ccd318/32.png) [@RogerDis](https://boards.straightdope.com/u/RogerDis)\
**Post date:** [November 21, 2012, 6:28pm UTC](https://boards.straightdope.com/t/calorific-values/641749/1 "2012-11-21T18:28:19Z")

</div>

How are the calorific values of foods determined?

---

<div class="post-metadata">

**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\
**Post date:** [November 21, 2012, 6:38pm UTC](https://boards.straightdope.com/t/calorific-values/641749/2 "2012-11-21T18:38:49Z")

</div>

Cecil’s article:

> **[How is the calorie content of foods determined?](https://www.straightdope.com/21341852/how-is-the-calorie-content-of-foods-determined)**

---

<div class="post-metadata">

**Author:** ![Michael63129](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@Michael63129](https://boards.straightdope.com/u/Michael63129)\
**Post date:** [November 21, 2012, 7:01pm UTC](https://boards.straightdope.com/t/calorific-values/641749/3 "2012-11-21T19:01:03Z")

</div>

> [@engineer\_comp\_geek](#):
>
> Cecil’s article:  
> [How is the calorie content of foods determined? - The Straight Dope](http://www.straightdope.com/columns/read/680/how-is-the-calorie-content-of-foods-determined)

In other words, they just measure how much fat, (digestible) carbohydrates and protein there is, which is probably easier to do than try burning (literally) a sample of food inside a closed container (and more accurate; substances like cellulose will burn but aren’t digestible). The calorie contents of different nutrients may vary slightly; I’d expect saturated fat to have slightly more energy than unsaturated fat because of the extra hydrogen atoms; there are also carbohydrates like sugar alcohols (counted separately) that can have considerably fewer calories.