One of the most common questions asked by new members is "How do I lean out?" While CrossFit will do amazing things for your body and mind, your results can be limited by the foods you put into your body. In a nutshell, you can't out train a poor diet.
The founder of CrossFit, Greg Glassman, summed up the simplicity in eating healthy for life in the “What is Fitness” Crossfit Journal article with these words:
Eat meat and vegetables, nuts and seeds, some fruit, little starch and no sugar. Keep intake to levels that will support exercise but not body fat.
–Greg Glassman, “What is Fitness?,” CrossFit Journal (Oct. 2002) pg. 1