vitamins that are absorbed directly into the blood
For the most part, the B vitamins are absorbed directly into the bloodstream in your stomach or small intestines. The exception is vitamin B-12, which must be bound to something called intrinsic factor for absorption.
Vitamin C is also a water-soluble vitamin that is absorbed directly into your bloodstream in your small intestines after it has been freed from food. Vitamin C is essential for good health and plays a number of important roles in your body.