Who has had knee pain? How did you deal with it?

After having had 7 surgeries in my college football career I started runningto stay in shape and maintain general health. Well with proper shoes and careful workouts I have survived nearly 20 years of running- 6 marathons and numerous 1/2 marathons-10 milers and other races. As the big guy I do these for run and a change of pace from regular running.
Recently had a bad twist of the left knee- the worst of my knees- and the pain has styed with me. I think the major challenge has been my weight. So doing my rehab I am also very seriously looking at my diet and weight. I know the impact dairy and salt plays and I am looking at some others. may go Vegetarian and raw. I will never get small but I hope to be reasonably small (255-265 lbs) and i think that may be the biggest tool to help my legs.

Anyone have any ideas- history?
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