You are always tired
Let’s understand calories first: A calorie is a unit of heat that breaks down by your body and then utilizes to sustain all your body’s functions in order to keep your organs healthy.
The number of calories you consume every day is based on your body’s height and length. Therefore, an adult will need more calories than a child to keep going throughout the day.
So, if your body doesn’t have enough calories, your body will fail to stay energized, which results in tiredness and fatigue, even if you didn’t do any physical activity during the day.