By Roberta H. Anding, M.S., Baylor College of Medicine and Texas Children’s Hospital

Edited by Kate Findley, The Great Courses Daily

Is it true that oatmeal lowers cholesterol? Yes, and Professor Anding explains the mechanism behind this process. She also discusses how Type 1 and Type 2 diabetes occur.

Oatmeal, Bile, and Cholesterol

Although most of the digestive process occurs in the small intestine, bile and the pancreas also play an important role. Bile, made by your liver and stored in the gallbladder, emulsifies, or mixes, the watery contents of your stomach with the fat in your meal so the fat can be attacked in greater force by your digestive enzymes. 

Bile is 70 percent cholesterol and is typically recycled, so we can think of our intestinal tract as a “green” organ. Our gut naturally recycles bile, and we don’t excrete it. 

However, when you eat oatmeal, the fiber in oatmeal binds to that bile. Instead of the usual recycling process, bile is eliminated when you have a bowel movement. Thus, your body has to make more bile. 

You may be wondering where your body gets the building blocks to make bile. If your bile is 70% cholesterol, this means your body is removing cholesterol from your blood to make bile, which is needed to emulsify the fat. 

Therefore, oatmeal does indeed lower your cholesterol, true to claim, by binding to the bile and causing it to be excreted. The gummy fibers in oatmeal are a valuable adjunct to the prevention of cardiovascular disease.

Additionally, many fiber supplements can be used for the treatment of constipation, and they’re particularly effective if they contain that gummy, gelling fiber.

The Pancreas’s Role in Diabetes

The pancreas is also vital to the digestive process. The pancreas, located near the small intestine, contributes valuable enzymes as well as hormones. It has two main functions.

• Exocrine function: making enzymes—lipase, amylase, and protease
• Endocrine function: producing hormones

The most notable hormone released by the pancreas is insulin, which is essential in physiological processing and disease management. Insulin is secreted by some specialist cells in the pancreas called “beta cells” and transports nutrients from the blood into the cells. It is an anabolic hormone, which means that it builds.

In human physiology, if we have an anabolic hormone, we’re going to have a counterpart, and the counterpart here is glucagon. Glucagon’s job is to break things down. 

Consider this. If you’re on a weight-loss diet, you want to break down your stored nutrients. You want to release them from the cells where they’re being stored, and you want them to be transported to other parts of the body to be used as energy. 

“I describe this as the yin and yang, the pulley system of human physiology,” Professor Anding said. “Insulin gets things in. It’s an anabolic hormone. Glucagon releases food. It is a catabolic hormone.”

The diseases associated with insulin and glucagon are often lumped under the umbrella term of “diabetes.” It’s a major endocrine disorder with two different types. 

Type 1 diabetes is autoimmune, which means that you actually destroy the beta cells of your pancreas. Type 2 diabetes is where you make enough insulin—in fact, oftentimes, you make too much insulin—but you don’t use it in an effective way, so the body makes more and more insulin.

If you’re making more insulin than you need, and you can’t use it for all of its transporting functions, you’ve got a bunch of hormones that say, “Store, store, store.” Oftentimes, people with Type 2 diabetes complain of significant hunger. Part of that is the overproduction of insulin linked with Type 2 diabetes.

Overall, both bile and the pancreas ensure that all of your bodily functions run smoothly. When issues occur in either of these areas, then high cholesterol or diabetes can result.  

This article was edited by Kate Findley, Writer for The Great Courses Daily.

Professor Roberta H. Anding is a registered dietitian and Director of Sports Nutrition and a clinical dietitian at Baylor College of Medicine and Texas Children’s Hospital. She also teaches and lectures in the Baylor College of Medicine’s Department of Pediatrics, Section of Adolescent Medicine and Sports Medicine, and in the Department of Kinesiology at Rice University. In addition, she is a registered dietitian with the American Dietetic Association and a dietitian for the Houston Texans NFL franchise.