Diet that increased body builder's strength & endurance

So what I gather from his talk was, he probably ate like crap, was a big meat eater (so that's what got blamed for his ailments and concerns of medical history), he then started eating from whole plant foods sources (thus he negated most processed foods he was probably consuming which were higher in calories and less filling) and assuming he had to eat a variety of plants, fruits, and grain sources to get enough complete protein and fiber in. So at the end of the day, he ate less calories, ate better/more healthy foods, lost weight, and felt better because he lost weight and ate a more balanced diet that had higher nutritional value.
The same could have been accomplished still incorporating meat if he so chose, but to each his/her own.