I enjoy travelling olanzapine vs ativan Every time you go more than two hours or so without eating, your blood sugar dropsâand that’s bad news for your energy. Here’s why: Food supplies the body with glucose, a type of sugar carried in the bloodstream. Our cells use glucose to make the body’s prime energy transporter, adenosine triphosphate (ATP). Your brain needs it. Your muscles need it. Every cell in your body needs it. But when blood sugar drops, your cells don’t have the raw materials to make ATP. And then? Everything starts to slow down. You get tired, hungry, irritable and unfocused.