One issue is that they add things to the vitamins, as well, like stearates which are fatty lubricants they use for whatever reasons as well as for the machines to easily encapsulate the formulations. Stearates are waxy large fat molecules that are hard for the body to break down and apparently sometimes get stuck in transit, and might cause other issues. Much of what they add your body has problems processing... We already do poorly with cellulose, and most supplements are loaded with it in various forms, from capsule itself to filler to meet pill volume requirements. Sometimes a product is mostly cellulose.
I'd love to be able to not take supplements. Unfortunately, I'm allergic to fucking everything, so I have to at least try. Or so says survival instinct.