I have tried oil pulling several times over the past 3 years or so. What would happen, unfortunately, is that once I did it several days in a row, I would get these very nasty canker sores in my mouth that would last for up to a week.
The first time it happened, I thought maybe it was a reaction to sesame oil, but the same thing happens with sunflower oil as well.
Right now, my plan is to oil pull once every 3 days and see if I can eventually get used to doing it more.
But maybe my more important question is this: what is causing this? While it may be a detoxification reaction (and I hope it is!), I would like more information, because I haven't seen much discussion of this problem.