Is there a natural treatment for lower back pain?

I have lower back pain, and have been looking for a natural back pain relief type treatment. What kinds of things can I do? Pilates, yoga, weights, massage are all good, but the only thing that really makes it feel any better is to go to the chiropractor. I get nervous about the adjustment because it usually hurts, but at least I feel better for a few hours, or a few days if I am lucky.

Someone suggested that it has something to do with stress and eating junk food, but I don't know how that could be. anything about any of that. any suggestions there?

Thanks