and how do you measure how many are in each type of fruit, veggie, nut etc?

A calorie is a unit of measurement for energy. Calorie is French and derives from the Latin calor (heat). In most fields, it has been replaced by the joule, the SI unit of energy. However, the kilocalorie or Calorie (capital "C" remains in common use for the amount of food energy.

Definitions for calorie fall into 2 classes:

The small calorie or gram calorie approximates the energy needed to increase the temperature of 1 gram of water by 1 °C. This is about 4.184 joules, and exactly 0.001 large calories.
The large calorie or kilogram calorie approximates the energy needed to increase the temperature of 1 kg of water by 1 °C. This is about 4.184 kJ, and exactly 1000 small calories.
In scientific contexts, the name "calorie" refers strictly to the gram calorie, and this unit has the symbol cal. SI prefixes are used with this name and symbol, so that the kilogram calorie is known as the "kilocalorie" and has the symbol kcal. In non-scientific contexts the kilocalorie is often referred to as a Calorie (capital "C", or just a calorie, and it has to be inferred from the context that the small calorie is not intended.

The conversion factor between calories and joules is numerically equivalent to the specific heat capacity of liquid water (in SI units).

1 calINT = 4.1868 J (1 J = 0.23885 calIT)
1 calth = 4.184 J (1 J = 0.23901 calth)
1 cal15 = 4.18580 J (1 J = 0.23890 cal15)



in other words ... Kcal is another word for Calories as we know them

...Jodi, the banana eating buddhist