Well, that depends on the type of supplement you’re talking about. There are two kinds: fat-soluble and water-soluble.
1. Tonik moves through the throat down into stomach.
2. Nutrients are broken down by the stomach acids.
3. The small intestine is where the absorption happens.
4. Water soluble vitamins & minerals are absorbed into the blood stream.
5. Fat soluble vitamins are absorbed into the lymphatic system.
6. No further digestion occurs in the large intestine.
You can read more about how it all works here.