Thanks for the ideas, Adrienne. I do take magnesium and chocolate (purely for medicinal reasons, you understand), and don't think I am eating anything often enough (except meat and coconut oil) for an allergy/intolerance to have a sustained effect. Right now I am cutting carbs almost to zero in order to get a baseline from which to calculate how much carb my blood glucose can tolerate, but I will make celery one of the first vegetables I add and see if it helps.
Andrea