# Calorie vs Kilocalorie **URL:** \ **Category:** Factual Questions\ **Created:** [November 11, 2009, 6:32am UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159 "2009-11-11T06:32:02Z")\ **Posts on this page:** 15\ **Page:** 2
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [November 12, 2009, 11:06am UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/21 "2009-11-12T11:06:19Z")
> [@rockypg](#): > > Why do food nutrition panels and Treadmill/Heartrate monitors use Calories and kilocalories so interchangeably with scant respect for the SI prefix kilo- ? Is this intentionally misleading figures on labels? It’s a conspiracy by the alien Visitors. By making it seem like there are fewer calories in food than there really are, they’re encouraging us to eat more, thus fattening us up for the future harvest. The scary thing is that it’s working. Just look around… ---
**Author:** ![Dead\_Cat](https://avatars.discourse-cdn.com/v4/letter/d/9fc29f/32.png) [@Dead\_Cat](https://boards.straightdope.com/u/Dead_Cat)\ **Post date:** [November 12, 2009, 1:00pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/22 "2009-11-12T13:00:45Z")
> [@qazwart](#): > > Well, the pound (a scientific unit of force) is officially defined as a certain weight in kilograms (a scientific unit of mass). So, it wouldn’t be unusual that the civilian “calorie” is actually a scientific kilocalorie. > > Your weight in pounds can vary depending upon the force of gravity. You weight 180 pounds on Earth, and you weigh about 30 pounds on the moon. Your mass in Kilograms won’t vary. You’ll have a mass of 82 kilograms on the earth and a mass of 82 kilograms on the moon. (Newton is the unit of force in SI and Slug is the unit of force in the PFS system of measurement). Er, pound is standardly a unit of mass, not force. Pound can also be used to denote force, but “Pound-Force” or “Pound-mass” should be used as appropriate for clarity where it is needed. ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [November 12, 2009, 1:35pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/23 "2009-11-12T13:35:30Z")
[quote=“1920s Style “Death Ray”, post:20, topic:517159”] How much is an American expecting? [/QUOTE] Well, we really only order “pints” in fancy brew pubs. Heck, we don’t even use the word “pub” unless we’re talking about fancy brew pubs. Anyway, a British and Canadian pint is 19.2 US ounces. ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [November 12, 2009, 1:50pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/24 "2009-11-12T13:50:38Z")
> [@Rigamarole](#): > > Oh no, someone isn’t respecting _le Système international d’unités_? CALL THE Système international d’unités POLICE! > > Oh wait, they’re all on paid vacation smoking cigarettes and eating cheese. Tough luck. See it would be very different if you wanted the the foot-pound police. _They_ are all out on paid disability leave, watching TV and eating doughnuts. ---
**Author:** ![cjepson](https://avatars.discourse-cdn.com/v4/letter/c/a9adbd/32.png) [@cjepson](https://boards.straightdope.com/u/cjepson)\ **Post date:** [November 12, 2009, 3:40pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/25 "2009-11-12T15:40:19Z")
> [@LSLGuy](#): > > Goinhg back to Calories, the bottom line is the public is butt-ignorant and utterly untrainable. You can add new things to their repertoire, like how to operate an iPod, but you could never introduce something called iPod which worked totally differently. The herd can’t do change > > So when the physicists redefined “calorie” from mks to cgs, The nutritionists were stuck. they settled on C calorie. Which worked OK when it was all new & everybody remembered there was an old. I suppose it worked OK when writing. But calorie and Calorie are pronounced exactly the same way, right? So whenever scientists actually talked about this stuff, wouldn’t they have to say “small-c calorie” just so the other person could be sure they weren’t using “Calorie” to mean “kilocalorie”? ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [November 12, 2009, 4:28pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/26 "2009-11-12T16:28:24Z")
> [@cjepson](#): > > I suppose it worked OK when writing. But calorie and Calorie are pronounced exactly the same way, right? So whenever scientists actually talked about this stuff, wouldn’t they have to say “small-c calorie” just so the other person could be sure they weren’t using “Calorie” to mean “kilocalorie”? As with most words calorie has a variety of meanings. You have to pick the specific meaning from context. If it is used in the context of food it is kilocalories. If for some reason you need to talk about the amount of energy in food and relate it to non food calculations you need to be more explicit or risk misunderstandings. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [November 12, 2009, 6:50pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/27 "2009-11-12T18:50:13Z")
[The Straight Dope - Calories versus kilocalories.](http://www.straightdope.com/columns/read/2738/why-do-americans-refer-to-the-main-course-of-a-meal-as-the-entree) ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [November 12, 2009, 6:57pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/28 "2009-11-12T18:57:07Z")
Hopefully, someone in the future will use Search and find this thread the next time this often-asked question arises. I was able to find no definitive reference to first documented use of the term calorie to mean “kilocalorie”, so I set off scanning through numerous works, both online and off (Cecil wanted me to look into it). The earliest use I was able to find was in W.O. Atwater’s “The Chemical Composition of American Food Materials”, published in 1896 as the United States Department of Agriculture Bulletin, Number 28. Starting on Page 11, he gives a huge list of the energy content of 2,600 food items, all listed in terms of “calories per pound”, referring to “kilocalories”. This use was confirmed in a later work by Atwater and Bryant in 1900. Atwater, who was a professor at Wesleyan University and later the first director of the USDA Office of Experiment Stations, is described by several texts as being the “father of modern American nutrition”, and he published numerous works on the subject from the middle of the 1800’s to the early 1900’s. It seemed likely to me as I went through similar papers and publications in the 1910’s-1930’s that many based their works on Atwater’s, and thus may have carried his usage forward. This is informed speculation on my part, not proven, however. It is possible that earlier researchers in this field used the word “calorie” to mean “kilocalorie” with respect to foodstuff (such as Justus von Liebig, J. Konig, and Jenkins and Winton) but if so no resources I could actually get my hands on had this usage. It was said that sometime in the 1880’s at least a couple of the guys I list had done so, but the texts were 1) in German, and 2) unavailable to me. Atwater, W.O. and Woods, Chas D. “The Chemical Composition of American Food Materials.” _USDA Bulletin Number 28_, 1896. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [November 12, 2009, 9:44pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/29 "2009-11-12T21:44:48Z")
> [@cjepson](#): > > I suppose it worked OK when writing. But calorie and Calorie are pronounced exactly the same way, right? So whenever scientists actually talked about this stuff, wouldn’t they have to say “small-c calorie” just so the other person could be sure they weren’t using “Calorie” to mean “kilocalorie”? Scientists never talk about calories - either big or little C. They talk joules. Also, metrified nations don’t talk calories in food either. All our food is labelled in kilojoules. On the other hand, the world is still clinging to calories, and so one gets pretty used to doing the conversion. My indoor rower insists on displaying energy dissipated in calories. We still get the silly effect where people talk about thousands of kilojoules. Really no different to distances being quoted in thousands of kilometers I guess. But when I say that the distance between Adelaide and Sydney is 1.4 megametres, I get a funny look. 😃 Although a 9 megajoule per day diet isn’t _quite_ so misunderstood. ---
**Author:** ![Superfluous\_Parentheses](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Superfluous\_Parentheses](https://boards.straightdope.com/u/Superfluous_Parentheses)\ **Post date:** [November 12, 2009, 9:49pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/30 "2009-11-12T21:49:10Z")
> [@LSLGuy](#): > > Just like when a Brit says he wants a pint he’s not talking about the same quantity as when an American says he wants a pint. What, what?! I can only imagine American pints are actually gallons or something… > [@Balthisar](#): > > Well, we really only order “pints” in fancy brew pubs. Heck, we don’t even use the word “pub” unless we’re talking about fancy brew pubs. Anyway, a British and Canadian pint is 19.2 US ounces. Well I know US ounces aren’t like Dutch ounces (which are 100 grams) (by the way: are those fluid ounces?), and a British pint is slighly less than 500 ml. So how much is 19.2 US (whatever-)ounces in SI units? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 12, 2009, 9:54pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/31 "2009-11-12T21:54:48Z")
An American pint is 16 ounces, rather than the 20 ounce Imperial pint. ---
**Author:** ![Superfluous\_Parentheses](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Superfluous\_Parentheses](https://boards.straightdope.com/u/Superfluous_Parentheses)\ **Post date:** [November 12, 2009, 9:57pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/32 "2009-11-12T21:57:37Z")
Thanks. For the interested, according to google: 1 Imperial pint = 568.261485 ml = 20 Imperial fluid ounces (so actually more than I thought) 1 US pint = 473.176473 ml = 16.6534768 Imperial fluid ounces ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [November 12, 2009, 10:10pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/33 "2009-11-12T22:10:32Z")
> [@Francis\_Vaughan](#): > > Scientists never talk about calories - either big or little C. They talk joules. > > Also, metrified nations don’t talk calories in food either. All our food is labelled in kilojoules. On the other hand, the world is still clinging to calories, and so one gets pretty used to doing the conversion. My indoor rower insists on displaying energy dissipated in calories. We still get the silly effect where people talk about thousands of kilojoules. Really no different to distances being quoted in thousands of kilometers I guess. But when I say that the distance between Adelaide and Sydney is 1.4 megametres, I get a funny look. 😃 Although a 9 megajoule per day diet isn’t _quite_ so misunderstood. So do dieters count their calories or their joules or their kilojoules? ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [November 12, 2009, 10:13pm UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/34 "2009-11-12T22:13:19Z")
> [@Francis\_Vaughan](#): > > Also, metrified nations don’t talk calories in food either. All our food is labelled in kilojoules. In Mexico the cloned-from-America nutrition labels all indicate “kcal” for energy content. My bottle of mineral water does also indicate kJ, though. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [November 13, 2009, 5:28am UTC](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159/35 "2009-11-13T05:28:55Z")
> [@gazpacho](#): > > So do dieters count their calories or their joules or their kilojoules? Calories or kilojoules. But it is a generational thing. Foods are in kilojoules, so most people do it in kilojoules. I do. Personally I divide the day into 9 one megajoule portions. Breakfast is 2, lunch 2 or 3, and so on. But most people talk in thousands of kilojoules for food and diet. I’m just bloody minded about correct use of the multiplier 🙂 My parents do Calories. [Previous page](https://boards.straightdope.com/t/calorie-vs-kilocalorie/517159.md?page=1)