All I can tell you is that Slippery Elm Soothes the intestinal tract. You can have D when your IT gets inflamed or irritated because of things like....medication,trigger foods,stress etc.
The SElm soothes the membrane of your IT so that it isn't irritated.
I think of it lik ethis...when you have a sore throat and it looks all red and burns to swallow. When you take medicine to soothe your throat like cough drops or liquid medicine....your throat is no longer sore and it doesn't hurt to swallow.
Since your intestinal tract has a job..pushing through waste...when it is irritated,it pushes that waste through as quickly as possible. If you tend to be C then your intestinal Tract locks up and refuses to move.The Slippery Elm soothes the lining and allows your bowels do do their job.
-------------------- IBS-D since 1999...mostly stable..i do cheat too.Bad me.