Nutrition and Anatomy

Since the beginning of the month, I've been working with students and their nutrition class. Last week, they looked at carbohydrates and this week's lecture topic is lipids. In order to encourage participation, the teacher requires that the students post onto a discussion board.

Here's what we came up with together in response to the given prompt:



Fat Digestion
How would removal of the gallbladder impact fat digestion? You might want to do a little research before answering this question since the answer to this question may not be as obvious as it first seems.

The gallbladder is an organ that lies directly under and abutting the liver. A duct system allows the gallbladder to be connected to the liver and the upper portion of the small intestine. The removal of the gallbladder would not entirely inhibit fat digestion. Instead, by removing the gallbladder, the rate at which lipids are emulsified and the total quantity of lipids emulsified would decrease.

Fat that arrives at the duodenum of the small intestine triggers a hormonal response that causes the gallbladder to release bile into the duodenum to deal with the fat. The enzymes that digest fat can only work on the surface of the fat globules. Indirectly, chemical digestion and ultimately absorption would be affected in the small intestine. Here in the small intestine chemical digestion occurs via lipase, which is assisted by bile from the liver and gallbladder. The positive feedback of a hormone trigger from the small intestine would no longer exist. Once a fat or lipid arrives in the duodenum of the small intestine, there would be no affect like triggering the gallbladder contraction of bile into the small intestine. There would also be a decrease in lipase activity since the presence of bile normally increases lipase action.


Bile is originally produced in the liver. This bile is made from cholesterol and stored in the gallbladder. The gallbladder stores excess, unused bile and concentrates it. This bile is only then secreted via feedback mechanisms when needed. As an emulsifying agent, bile breaks down large fat droplets into smaller droplets known as micelles, whose surface area allows for lipase activity. In other words, the bile acts as a detergent on the fat and causes the large fat globules to break down.


The removal of the gallbladder would mean that there would just be no storage center for excess, unused bile. However, at the time of digestion by lipase, there would be adequate, yet limited amounts of bile. When this initial amount is used up, the body and digestive system would have to wait accordingly until the liver can produce more necessary bile for emulsification. This waiting period indicates that there is a lag time where no emulsification is occurring, or decreased rate, and the presence un-emulsified lipids, halting digestion.

In real life stories, patients have reported their own gallbladder removal. Their post-operative comments and lifestyle adjustments have indicated changes from less fat consumption in their daily diet, reduction of spicy foods as well as alcohol, which are shared in an online blog found here at http://www.hgriggs.com/gallbladder.html#threeyears .


"2001: A Gall Bladder Removal." Hedonism with Henry. 30 May 2004. Web. 22 June 2011. .

"Digestive System." MCAT Review. MCAT Review and MCAT Prep Online, 2008. Web. 22 June 2011. .

Farr, Gary. "The Gallbladder." BecomeHealthyNow.com - Your Source for Natural Health Care with Results. BecomeHealthyNow.com, 20 June 2003. Web. 22 June 2011. .