I've had an anal fissure for about two months. I think I am finally on the road to healing. The road was very difficult, with at least three re-tears and a lot of pain and anxiety.
I wanted to share a key insight that came about in my case.
Most of the "patient education" materials that I got from my colorectal surgeon emphasized the importance of a high fiber diet, among other things. They also primarily gave examples of *insoluble* fiber, when talking about fiber. After a fair amount of experimentation and work with physical therapist who were skilled with dietary matters, we made a key discovery. Primary reliance upon insoluble fiber is precisely the *wrong* thing to do. Insoluble fiber bulks up my stool and increases its diameter, which increases the risk of passing stool that re-tears my AF. Soluble fiber, by contrast, does not bulk up stool, but instead makes it softer, soupier, and more gelatinous. Once we realized I was inappropriately and dominantly emphasizing insoluble fiber, I switched to primarily eating beans, pears, oats, etc., instead of whole wheat bread, bran cereal, etc. The change was dramatic. It became so much easier and less painful to pass stool associated with a dominant emphasis on soluble fiber.
Perhaps each of our bodies is so idiosyncratic that my personal learning may not apply to others. However, if our bodies generally treat soluble fiber in the same way, I would highly recommend that everyone who is trying to heal his or her AF move away from insoluble fiber and use a more balanced mix of soluble and insoluble, or try what I did... a move to primary emphasis on soluble fiber. I hope this may help my fellow sufferers, in case it applies to your body as well.