we can measure food energy and body energy by using calorie.

whereas force energy or light energy can be measured by using joule.

4 joules= 1 calorie

1 calorie is equal to 4.1868

hope this help you.....
1 5 1
any energy can be measured by calorie or joules.. We are used to writing in calories due to habit from centuries. we use joules for scientific calculations in general..
1 calorie = 4.18 joules 

1000 calories = 1 Calorie 

The Calorie (with a capital C) is the nutritional calorie. 

One joule is the work done, or energy expended, by a force of one newton moving one metre along the direction of the force. This quantity is also denoted as a newton metre with the symbol N x m. 

1 J = 1 N x m 
1 J = 1 kg x m^2 / s^2 

The joule is also used in other types of measurements, such as coulombs and kilowatt hours.