Absorption[edit]
Although the absorption in the human stomach is mainly a function of the small intestine, some absorption of certain small molecules nevertheless does occur in the stomach through its lining. This includes:
- Water, if the body is dehydrated
- Medication, like aspirin
- Amino acids[10]
- 10–20% of ingested ethanol (e.g. from alcoholic beverages)[11]
- Caffeine[12]
- To a small extent water-soluble vitamins (most are absorbed in the small intestine)[13]
The parietal cells of the human stomach are responsible for producing intrinsic factor, which is necessary for the absorption of vitamin B12. B12 is used in cellular metabolism and is necessary for the production of red blood cells, and the functioning of the nervous system.