Food and Human Health Issues: GALLSTONES

1. Food and Human Health Issues:GALLSTONES

2. The Gallbladder:Basic Anatomy The gallbladder is… … an accessory organ in the digestive system. … a small (4-inch) greenish sac with thin, muscular walls. … located just underneath the liver … connected to the liver by several tubes or ducts – the hepatic duct and the cystic duct. … connected to the duodenum of the small intestine by the bile duct (Marieb 2009; A.D.A.M. 2009)

3. Human Digestive System (image from Zieve & Longstreth 2009)

4. Bile duct sphincter (Image from http://adam.about.com/reports/Gallbladder.htm)

5. What is Bile? • Bile is a watery, yellow-green fluid made in the liver, stored in the gallbladder, and released into the small intestine • Bile contains water, many bile salts, cholesterol, phospholipids, and bilirubin (a pigment) • Bile is essential for fat digestion in the small intestine: it acts like soap to break apart large fat globules into smaller pieces (so that enzymes can more easily digest them) (Marieb 2009)

6. Gallbladder Physiology: How It Works • The gallbladder’s function is to store bile, which helps digest fats in the duodenum of the small intestine • Bile made in the liver drains into hepatic ducts and down into the bile duct • When no fat digestion is occurring: • Bile duct sphincter is closed • Bile flows up the common hepatic duct and • cystic duct and is stored in the gallbladder for later use • When fat digestion is occurring: • A hormone called cholecystokinin is released when food enters the duodenum • Cholecystokinin signals the bile duct to open and the gallbladder walls to contract • This pushes bile from the gallbladder through the ducts and into the duodenum (Marieb 2009; A.D.A.M. 2009) (image from A.D.A.M. 2009)

7. GALLSTONES: An Overview Gallstones are hardened crystals of bile that can form in the gallbladder. They can get stuck either in the gallbladder itself, or in the ducts connecting the gallbladder to the small intestine. Gallstones are a problem because… • They can be painful due to their hard/sharp edges – it hurts when the gallbladder contracts. • They can cause digestive complications when they block fluid in the ducts from entering the small intestine. (Mayo Foundation 2009; Marieb 2009)

8. Normal Gallbladder Anatomy Gallstones Disrupt Normal Anatomy

9. A Closer Look at Gallstones: • Gallstones can range in size from as small as a grain of sand, to as large as a golf ball! • There are two main types: • Cholesterol gallstones are yellow in color, and are caused by too much cholesterol in the bile • Pigment gallstones are brown or black, and are caused by too much bilirubin in the bile • Gallstones can also be caused by a malfunction in the gallbladder itself – if it doesn’t empty properly, the bile can get overly concentrated and form stones. (Mayo Foundation 2009)

10. Physiological Complications of Gallstones In addition to possible attacks of sharp pain, gallstones can result in a number of complications affecting other digestive organs: • If a stone blocks the opening of the gallbladder  bile builds up in the gallbladder, causing inflammation and possible pain & fever • If a stone blocks the common bile duct  the bile duct can become infected • If a stone blocks the pancreatic duct  pancreatic enzymes build up in the pancreas. This can irritate the pancreas tissues and cause inflammation (pancreatitis) • Blocking the flow of bile and/or pancreatic enzymes to the duodenum makes digestion of fats, as well as carbohydrates and proteins, more difficult – can lead to slight malnutrition due to inability to break down and absorb nutrients and fat-soluble vitamins (Mayo Foundation 2009)

12. How Does FoodRelate to Gallstones?

13. Gallstones are caused by a combination of genetic and dietary factors. Food-related risk factors include: • Diet high in cholesterol • Diet high in saturated or trans fats • Diet high in refined carbohydrates • Diet low in fiber • Eating a consistently high-calorie diet • Being overweight or obese • Loosing weight extremely rapidly, or extended fasting • Having diabetes (Mayo Foundation 2009; Hayes et al. 1992)

14. Why Can a Poor Diet Lead to Gallstones? Medical research has not yet been able to fully explain the links between food and gallstones. However, possible mechanisms include: • Eating high amounts of cholesterol, saturated fat, or trans fat can raise the amount of bad cholesterol (LDL) in your blood. • This cholesterol can get picked up and brought to the liver, where it is “disposed of” in bile. • Eating a high-calorie diet also changes your metabolism in a way that makes the liver produce more cholesterol. • Both of these factors lead to bile with too much cholesterol, which triggers the formation of cholesterol-based gallstones (the most common kind). (Zanlungo et al 2004; Hayes et al. 1992)

15. Eat Right to Manage and Prevent Gallstones! • Eat a diet high in fiber (whole grains, fruits, and veggies)  The fiber pushes fats along the digestive tract more quickly, which makes the liver release a lower-cholesterol bile • Eat “healthy” fats such as mono- and poly-unsaturated fats from nuts, seeds, and fish  Consuming these instead of saturated or trans fats will lower your overall LDL (“bad cholesterol”) • Maintain a healthy weight by eating the right number of calories and getting regular exercise. • If trying to lose weight, do it slowly and don’t skip meals! (Mayo Foundation 2009; Zanlungo 2004)

16. Crunchy Wasabi-Lime Salmon with Red Cabbage and Sugar Snaps (served over brown rice) Crunchy Wasabi-Lime Salmon with Red Cabbage and Sugar Snaps (served over brown rice) This recipe uses wasabi-coated peas (a great snack food found in many supermarkets) as a crushed, crunchy topping for salmon – which contains unsaturated fats good for reducing cholesterol and preventing gallstones. The simple stir-fry of red cabbage and sugar snap peas provides beautiful color as well as delicious taste. Served over steamed brown rice, this provides an excellent source of fiber to help reduce the cholesterol in bile. Recipe: This recipe uses wasabi-coated peas (a great snack food found in many supermarkets) as a crushed, crunchy topping for salmon – which contains unsaturated fats good for reducing cholesterol and preventing gallstones. The simple stir-fry of red cabbage and sugar snap peas provides beautiful color as well as delicious taste. Served over steamed brown rice, this provides an excellent source of fiber to help reduce the cholesterol in bile. Recipe: Recipe from Eat Fresh Food: Awesome Recipes for Teen Chefs by Rozanne Gold (2009) Recipe from Eat Fresh Food: Awesome Recipes for Teen Chefs by Rozanne Gold (2009)

17. Works Cited • A.D.A.M. In-Depth Reports. (2009, Sept. 4) Gallstones and gallbladder disease. Retrieved on Feb. 21, 2010 from http://adam.about.com/reports/Gallstones-and-gallbladder-disease.htm • Gold R. (2009.) “Crunchy Wasabi-Lime Salmon with Red Cabbage and Sugar Snaps.” Eat Fresh Food: Awesome Recipes for Teen Chefs. New York: Bloomsbury • Hayes KC, Livingston A, Trautwein EA. (1992.) Dietary impact on biliary lipids and gallstones. Annual Review of Nutrition12: 299-326. • Marieb, E.N. (2009.) Essentials of Human Anatomy & Physiology (9th ed.) Boston: Pearson/Benjamin Cummings. • Mayo Foundation for Medical Education and Research (2009, July 25). Gallstones. Retrieved on Feb. 20, 2010 from http://www.mayoclinic.com/health/gallstones/DS00165 • Zanlungo S, Rigotti A, Nervi F. (2004.) Hepatic cholesterol transport from plasma into bile: implications for gallstone disease.Current Opinions in Lipidology15(3):279-86. • Zieve, D and Longstreth GF. (2009, August 1.) Digestive System. Retrieved from Medline Plus Online Encyclopedia on Feb. 20, 2010. http://www.nlm.nih.gov/medlineplus/ency/imagepages/1090.htm