When leaning up, there is nothing that works better than bumping up your protein at the expense of your carbohydrate intake. Many people believe that means upping their meat intake, and in the case of some meats, it means overindulging on saturated fat -- the worst of the worst for your health. In fact, you can eat less meat and more of certain vegetables and nuts and end up leaner and healthier.
Take a look at his article from Shine entitled, "8 veggies, nuts, and grains with more protein than a burger."
Train hard; diet harder.