I love the stuff. And I remember a teacher/coach from High School actually making it in class and telling us how good it was for us because of the 'active' cultures and how they help the overall digestive process.

Even after you've ate it, the live cultures stay in your guts for awhile and keep working. This was a lifetime ago, so I don't remember all the details.

Back to your original question...
Haven't heard anything about yogurt affecting MS in any way. Good or bad.

But that's just me...