In article , Han wrote:
"J. Clarke" wrote in
:

While you make some interesting points, if you are going to whine
about the calorie being part of the metric system, please find an
official statement by anybody to the effect that it actually _is_ part
of the metric system.

It's a trivially small measure of heat. That amount of heat necessary to
raise the temperature of 1 ml or 1 gram of water by 1 degree centigrade.
Fudge with starting temperature and standard pressure to get a bit more
accurate.

When talking calories, I believe, the prefix kilo is often discarded, hence
the notion that the above 1 gram should be replaced by 1 kilogram.
However, the 1 gram, 1 degree thing is the "official" definition.

It depends on who's doing the talking. To a physicist or chemist, "calorie"
refers to heating 1 gram of water, as stated above. What a nutritionist calls
a "calorie" (e.g. what you see on the label of a can of beans) refers to
heating 1 kg of water, and the scientist calls it a kilocalorie.