Question

explain the details of lipid digestion and absorption. use scholarly resources.

Answer 1

Digestion and absorption of lipids

Lipids consist of 90% triglycerides. Lipids are not water soluble and form as droplets so it does not mix with intestinal contents. There are 3 enzymes that help in lipid digestion are lingual lipase, gastric lipase, and pancreatic lipase. Pancreatic lipase is secreted by the pancreas and enter into the duodenum. So most lipid digestion occurs in duodenum.

Majority of fat forms as droplets and is not digested when it reaches the small intestine. Bile mixes with the fat globe. Bile salt acts as an emulsifier of lipids and breaks large fat droplets into smaller droplets. Pancreatic lipase acts on these smaller droplets and breaks it down into free fatty acids and monoglycerides which are more easily absorbed.

Free fatty acids and monoglycerides pass the intestinal mucosa and enter the epithelial cells of the small intestine. They enter the endoplasmic reticulum which helps in the synthesis and transport of lipids. Here the digestive products are resynthesized to triglycerides, forms stored fat in the body. In the epithelial cells triglycerides along with protein to form chylomicrons, it is water-soluble and enters into the lymphatic capillaries called lacteals in the villi of the intestinal wall. Then it enters into the blood stream.