Kid boy, let me tell u more i suffered loose motion today from early morn, had to go to the loo 20 times. So each time the amount of fluid was wasted from my body, energy equal to 100 calories was lost. S boy here u go, 20*100= 2000 cal. lost in a matter of 4 hours. tummy infested with virus: So to replicate they need energy - so for the making 20 billion tummy viruses inside my tummy - energy lost 1000 cal.