I think flax is IF. They recommend it for making us go. I don't know where you read it was soothing, I find it just the opposite (and I think I read about this somewhere, but I don't have the time to look for it, sorry)
I wouldn't take it with the morning cereal, what I do is sometimes I add it to my evening smoothie (when I have time to make it) and I can't do more than 1 teaspoon...