I told you this one would be tricky! The correct answer is Neither!
Both peanut and regular M & M's contain, or may contain peanuts. This is one of the hardest candies for me. Since being diagnosed with my peanut allergy, I have easily adapted to my new nut-free diet. But, the fact that I haven't been allowed to eat regular M & M's since seventh grade kills me. This is one candy I look forward to hopefully being able to eat again someday after completing the peanut study.
Keep out of the nut house!