Go on the Perricone Diet that is recommended in Dr. Nicolas Perricone's book called "The Perricone Prescription".
When you see the before's and after's in this book based on what a good diet can do to help your skin and aging, then you will learn to like healthy foods knowing that you will be making a huge difference to your physical well being and guard against aging too fast.
In this book, he has a 3 day and 28 day diet. Stick to the 28 day diet as long as you possibly can and you will see a huge difference in your physical well being and health.
Clear your pantry, refrigerator, and house of any foods that are not on the "recommended list"-- and only purchase the foods that he has on his lists.
When you go to a restaurant, try to stick as closely to his recommended foods.
In a few months, you won't believe that you have ever eaten foods that are NOT healthy.
Allow yourself one or two meals a week where you eat the old stuff that you used to like. Don't try to quit these completely "cold turkey". When you see how much better you feel with the recommended foods, it will be a very easy switch!