A healthy food diet is a life eating plan rather than a short term fad diet (fad diets do not work because your body does not get all its required nutrients and you end up with hunger pangs and cravings).
Carbohydrates, proteins, fats, minerals, vitamins and liquid are all essential for our body to work it's best. A good selection of vegetables, fruits, grains and proteins is necessary and eating regular meals rather than just one huge one is better for you.
Your chances of getting diabetes, heart disease, high blood pressure and cancer are all greatly reduced by eating healthy. A poor diet can result in obesity, lethargy and spotty skin. A good diet will help you maintain a healthy weight which is a big factor in overall health.