How Digestion Works

Normally, food that is digested eventually makes it way to the liver and then delivered to the body’s cells to sustain life.  However, fatty food products do not enter the bloodstream as do other foods.  They are taken up from the intestine through ducts in the villi called lacteals.  Lacteals connect with the lymphatic system whereby these fatty molecules eventually drain into the thoracic duct.  The thoracic duct empties into the vena cava in the neck area and this process allows the fats to enter the bloodstream where they pass through the liver for metabolic adjustments.

In the ileum portion of the small intestine, there are nodules of lymphoid tissue known as Peyer’s patches.  These lymph tissues contain scavenger cells of lymphocytes which have a protective function by attacking and destroying unwanted bacteria and other undesirables that find their way into the intestines.

The small intestine averages 20 to 22 feet in length and is from 1-1/4 to 1-1/2 inches wide throughout these 20-22 feet.  The ileum ends at the base of the large intestine in the right lower section of the abdomen.

Within 8 to 10 hours of eating, the food has passed through the small intestine and is mostly digested and then enters the large bowel for the final digestive processes and eventual elimination from the body.

The colon is made of 6 sections:  the cecum, ascending colon, transverse colon, descending colon, sigmoid and rectum, so it’s about 5 feet long and 2-1/2 inches in diameter.  The cecum is a blind pouch whose open end joins the ascending colon as it ascends upward toward the first bend called the hepatic flexure.  Here at the cecum is found the ileo-cecal valve, a sphincter muscle which controls the flow of raw materials of food from the small and large intestine.