Our bodies need a range of foods to give us the right kind of 'fuel' we need.
This is what we call a balanced diet. But the foods we need are not all the ones we most like to eat, because our taste buds urge us to eat salty and fatty things, rather than fruit and vegetables.
It's a hang-over designed to make us eat the most important foods in times when we might starve and when we did not live very long.
