I have never been on a diet. I have always tried to eat healthy. I have seen too many people waste away eating junk food, not knowing how to even cook something simple like pasta. We cook almost every meal at my house, all from scratch. And all pretty healthy. It is not perfect, but it is so much better then buying pre-made packaged food from the store, or going out to eat every meal.
If you are looking to eat healthier and cook your own meals. I would suggest getting some professional cook books. Ones by chefs for chefs. They are slightly harder to follow along with at home, but the food is so much better and healthier. They use less pre-made ingredients, and more raw products.