Simple balanced diet. Here's a couple of additional tidbits.

1) My endocrinologist told me..."Do you have those big dinner plates like everyone does now? If so, get rid of them. They are too big. Use the salad plates instead."
2) Make your plate 50% green veggies and the like, 25% carbs, 25% proteins.

Oh, one last thing. My wife has done this with me. She has always been slender and in great health. Since we are doing this together, she even lost 15 pounds and looks awesome and is healthier and happier. This all has been a game-changer for us.