Pat, The calorie is FAR older than Lulu. She may or may not have been the first to apply it to nutrition. http://en.wikipedia.org/wiki/Calorie Some snippets from this source: "The calorie is a pre-SI metric unit of energy. The unit was first defined by Professor Nicolas Clément in 1824 as a unit of heat. This definition entered French and English dictionaries between 1841 and 1867.[1] In most fields its use is archaic, having been replaced by the SI unit of energy, the joule. However, in many countries it remains in common use as a unit of food energy. In the context of nutrition, and especially food labelling, the terms calorie (or Calorie) and kilocalorie are interchangeable. In either case the unit is approximately equal to 4.2 kJ. . . . . The original definition by Clément was based on the kilogram. Other definitions based on the gram have since been made. We thus have the two major variants: the kilogram calorie and the gram calorie. One thousand gram calories equal one kilogram calorie. In the context of food energy the term calorie generally refers to the kilogram calorie. However, the term kilocalorie (kcal), referring to one thousand gram calories, is also in widespread use especially by professional nutritionists (when speaking in terms of calories rather than joules). To avoid confusion, the prefix kilo- is not used with the kilogram calorie.
Kilogram calorie The kilogram calorie, large calorie, food calorie, Calorie (capital C) or just calorie (lowercase c) is the amount of energy required to raise the temperature of one kilogram of water by one degree Celsius." It has always been defined as the energy to heat 1 g or 1 kg of water by 1 °C. Unfortunately the starting and ending temperature were not made part of the definition, and the heat capacity of water is not constant. Certainly, in high school physics, I learned the calorie for thermal energy, and an experiment called "the mechanical equivalent of heat" related it to the joule. Lulu's calorie is merely the nutritional or kilocalorie cast into familiar Imperial terms; it has never been measured as she describes it. It was not until 1948 that the CPGM deprecated the calorie (the various calories?) in favor of the joule for thermal energy. Nutritionists were slower to follow. This seems to be the official in view of WHO: http://www.fao.org/docrep/meeting/009/ae906e/ae906e17.htm While discussions began in 1966 (or earlier?), the recommendation appears to have been adopted (as gradual conversion) in 1969. --- On Sat, 7/18/09, Pat Naughtin <[email protected]> wrote: From: Pat Naughtin <[email protected]> Subject: [USMA:45428] Re: Names of old measuring methods To: "U.S. Metric Association" <[email protected]> Cc: "U.S. Metric Association" <[email protected]> Date: Saturday, July 18, 2009, 10:55 PM On 2009/07/18, at 10:22 AM, John M. Steele wrote: I don't know who Lulu is, but in her defense, her calorie is closer to a calorie than many calories are. Dear John, Here is a little background to Lulu Hunt-Peters in the context of energy measurements. In this context it is interesting to note that Dr Lulu Hunt-Peters has been highly successful at changing the world of food measurement to her idiosyncratic and unscientific measuring word at the same time as the entire world of metrology has clearly failed to promote their point of view. Dr Hunt-Peters did not have government support, she did not have the support of the scientific community, nor did she did not have any legal precedence. Basically, all she had was the ability to write for women's magazines, and with that talent she changed the entire world of measuring the energy in food. Think about the competition between the internationally recognised metric unit for food energy, kilojoule, and some of the other common measuring words such as, calories, Calories, gram calories, kilocalories, or kilogram calories. Dr Hunt-Peters succeeded while the world of scientific metrology failed! You can find an outline of Lulu Hunt Peters life at http://calorielab.com/news/2005/09/16/lulu-hunt-peters-and-the-birth-of-the-modern-diet-book/ and a copy of her main book from http://www.gutenberg.org/etext/15069 Here is a summary of the history of food energy. There has been only one official metric unit for measuring food energy since 1889 — kilojoules. For example, a slice of bread contains about 250 kilojoules of food energy and a sweet biscuit has about 500 kilojoules of food energy. The kilojoule had been accepted as the sole unit for energy internationally since 1889. However in 1918, 29 years after the establishment of the kilojoule as an international standard unit for measuring the energy in food, Dr Lulu Hunt Peters popularised an alternative word, 'calorie', to describe food energy in the USA. However, she avoided defining the concept of food energy by writing, '… hereafter you are going to eat calories of food. Instead of saying one slice of bread, or a piece of pie, you will say 100 calories of bread, 350 calories of pie.' Food energy and measuring have been profoundly muddled ever since the publication of the book, Diet and Health in 1918. As a child, Lulu Hunt Peters was aware of her problem with body mass when she wrote, '… that there is genuine mental suffering in being an obese child.' She knew this from her own experience as a child and, as an adult, she reached a body mass of 100 kilograms when the body mass of an average woman was close to 65 kg. Dr Hunt Peters defined a calorie as the amount of heat needed to heat 4 pounds of water by 1 degree Fahrenheit. She based her definition on the German research into dog digestion done by W. O. Atwater who was investigating the best way to use dog droppings for tanning leather. Many attempts were made later to define the word, calorie, in metric terms. For example, the size of a calorie depends on the temperature at which it is defined; technically on a scale of 32 to 212 degrees Fahrenheit there are 180 possible definitions for the word, calorie. But this only led to more confusion as different groups then devise different definitions for the different ways that a calorie might be spelled; one example is that a Calorie (with an upper case C) is 1000 times larger than a calorie (with a lower case c). This is why we have: calories, Calories, gram calories, kilocalories, kilogram calories, and perhaps 20 or 30 other spelling varieties with potentially different values. Like other old pre-metric measures there are now far too many different calories (or Calories or kilocalories) that have many different names and varying values. The existence of these seemingly good choices (kilojoule accurate, the others popular) means that the debate between them will continue for many generations, with nutritionists and dieticians dithering between them. To a measurement specialist there is only one choice, the kilojoule, but I suspect that women's and diet magazines will continue dithering. You can only avoid dithering by adopting a definite measurement policy for yourself or the group that you represent. When you write: 'her calorie is closer to a calorie than many calories are' you are accepting the definition of one group, in one place, who have defined the word calorie according to their own requirements. To the best of my knowledge, no international authority has been able to define a 'universal calorie. For example, BIPM (at http://www1.bipm.org/en/si/si_brochure/chapter4/table10.html ) simply notes that a number of different calories have been used in the past, they write: i) Several "calories" have been in use: a calorie labelled "at 15 °C": 1 cal15 = 4.1855 J (value adopted by the CIPM in 1950; PV, 1950, 22, 79-80); a calorie labelled "IT" (International Table): 1 calIT = 4.1868 J (5th International Conference on the Properties of Steam, London, 1956); a calorie labelled "thermochemical": 1 calth = 4.184 J. Cheers, Pat Naughtin Author of the forthcoming book, Metrication Leaders Guide. PO Box 305 Belmont 3216, Geelong, Australia Phone: 61 3 5241 2008 Metric system consultant, writer, and speaker, Pat Naughtin, has helped thousands of people and hundreds of companies upgrade to the modern metric system smoothly, quickly, and so economically that they now save thousands each year when buying, processing, or selling for their businesses. Pat provides services and resources for many different trades, crafts, and professions for commercial, industrial and government metrication leaders in Asia, Europe, and in the USA. Pat's clients include the Australian Government, Google, NASA, NIST, and the metric associations of Canada, the UK, and the USA. See http://www.metricationmatters.com for more metrication information, contact Pat at [email protected] or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter to subscribe.
