Answer:
What can bring back the dead. Make us cry, make us laugh, make us young. Born in an instant yet lasts a life time?
What contains zero calories, but if you consume it, you will probably gain weight?
Two brothers we are, great burdens we bear. All day we are bitterly pressed. Yet this I will say, we are full all the day, and empty when go to rest.
Until I am measured I am not known, Yet how you miss me when I have flown.
Both punishment and sweet reward, It will befall both fool and lord. It is a spiritual scoreboard, Your every deed it does record.
You use it between your head and your toes, the more it works the thinner it grows.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?