Actually I am a believer in the mainly vegetarian lifestyle. There is a book (The China Study)- and an ongoing study- that is a result of 20-year partnership of Cornell University, Oxford University, and the Chinese Academy of Preventive Medicine. They have 20 years of empirical data showing a huge cross-section of lifestyles in Taiwan and many rural areas. Dr. Colin Campbell headed it up from the Cornell side.
They have documented clinical data that shows that a diet consisting of less than 10% of Protein coming from animal sources (most notably casein) can actually arrest development in cancer in lab rats. The people with the lowest incidences of cancer are the rural farmers who A) cannot afford huge amounts of animal protein and B ) move their bodies rather than drive their cars everyday. Even rural places impacted by China's terrible pollution problem have shown a notable avoidance from cancer.
Joel Fuhrman is another guy crusading for a more 'nutrative' vegetarian lifestyle. He is more toward the vegan side and is definitely worth checking out, but his program is very strict. His eating method has allowed diabetics to come off of insulin within the first three weeks.
IMHO I believe that the days of eating rich foods all of the time is over for me. I am OK with that, I had a good run . I think it's OK to have meat and cheese, as long as it is on a weekly or biweekly basis rather than a daily basis. I am post-op now, and still relying daily upon yogurt and cheese and eggs and whey powders, and I suspect I will continue to be as I lose over the next 18 months, but the long term plan is to steer towards plant-based protein sources and integrate them to get myself to that <=10% protein animal intake level.