There are many thread on this topic and some are quite vigorously debated. Rather than re-invent the wheel I would suggest you use the search function. I will try to post the liveliest of the many threads to get you started:
Fellow UK/English guy in that thread seems like he does not approve of Cannabis. Me personally, I do not understand scientifically how it would help inflammation and nobody here has been able to explain that to me.
There are many other threads, search under "marijuana" as well as "cannabis"