Digestion is the process of breaking food down so that nutrients can be absorbed by cells. In your ...
Read the full transcript »
Digestion is the process of breaking food down so that nutrients can be absorbed by cells. In your stomach, food is churned and mixed with acid and enzymes. It is then pushed into the first part of the small intestine, where most digestion and absorption takes place. To aid absorption, it is mixed with bile, which is produced by the liver and discharged from the gallbladder through ducts. Digested food molecules pass into blood vessels in the walls of the intestine and are carried up through the portal vein into the liver for further processing and storage. The liver is usually a rich, red color, but excess lipids stored in its cells can change it to a whitish color. This is known as fatty liver disease. It is closely associated with obesity, particularly central obesity involving the omentum, a fatty pad that hangs down from the stomach. Eating too much fat can cause it to push out, producing a large waist line. In some people, eating certain foods can irritate the walls of the small intestine and disrupt regular movement, resulting in altered bowel habits, or irritable bowel. Almost all nutrients have been absorbed by the time digested food leaves the small intestine and enters the colon, where water and salt are extracted leaving solid wastes for elimination.