Don't mean to bring back up a 2 month old topic, but I either read or heard from somewhere that heartburn can also be an indicator that you're not drinking enough water. You should be pounding that stuff down. I carry a 3-Liter jug with me (I typically won't drink all of it unless I do a heavy day of running) to track my water consumption. Being a runner and not drinking enough water is a nasty combo.
I went through a period, about this time last year actually, of acid reflux, but mine was stress related. I was constantly running every-every other day but never had the issue/pain during my runs. I went and saw my doc, he smiled and said I was fine, gave me 3 sample pills of an acid reflux med (can't remember what it was) and was fine afterward. I also made a point to lower my stress.
ANYWAY, I also recommend NOT to drink Green Tea while being extremely active. I always found myself puking on my runs when I drank green tea. Just stay away from caffeine and spicy foods.
Now that it's 2 months later have you improved any? What changes have you made?