Theoretically at least, vitamins (arguably) have effect when they are still circulating at your bloodstream. Some vitamins are cleared rapidly. Vitamin C might be 2 hours, and some B vitamins 4-6 hours. Each of the different nutrients could be formularized as having a different release profile, then combined into one steady state pill.
As a powder they could add this to breakfast cereals and petfood as well.-- beanangel, Aug 28 2017random, halfbakery