Calories - Maintain, Gain or Lose
If we get the balance right, “Calories in” matches or equals “Calories out” you will not gain or lose weight. Or put it another way, if you consume 2500 Calories and burnt off 2500 Calories in a single day, your body stays the same.
Sometimes people wish to gain weight, and to do this you would consume more Calories than you burn off in a single day. Or put it another way, if you consume 3000 Calories and burnt off 2000 Calories in a single day, your surplus would be 1000 Calories. Your body has no immediate use for these extra 1000 Calories, so there is only one thing it can do: store them into your body as extra fat or extra muscle.
This is the important part if you want to lose weight! If you want to lose weight, then your “Calories in” should be less then your “Calories out”. Or put it another way, if you consume 2000 Calories, and burn off 3000 you will lose weight. You put your body into a “Calorie Deficit”. In this case, 1000 calories. These extra1000 Calories needed to fuel you body have to come from somewhere. So your body gets them from your fat and muscle stores from around your body. So in a nutshell you lose weight.