I have a hard time taking vitamins (even those without iron) and prescription medicine without it causing unusually hard and large stools. I'm fairly regular so that's not the problem. I currently take Armour Thyroid for hypothyroidism and 1000 flax seed oil which helps with hot flashes (I'm in menopause). Is there a natural supplement or vitamin that could be taken daily to help soften stools? THanks.