Soluble Fiber
A major reason oatmeal reduces low-density lipoprotein (LDL), or bad, cholesterol is that it contains soluble fiber, according to the Mayo Clinic. The fibers appear to have the ability to reduce the absorption of cholesterol in your intestines. Just 10 g or more of soluble fiber a day decreases total and LDL cholesterol. Consuming 1 ½ cups of cooked oatmeal brings you 6 g of fiber. You can get that extra fiber you need to greatly reduce cholesterol by adding fruit, such as bananas, apples or pears, which also contain fiber.
Bile Acids
The water-soluble fiber is beta-glucan, widely prevalent in oats. It has a high capacity to hold water and becomes gooey when dissolved in water. As it travels slowly through the digestive tract, it attaches to bile acids in the intestine. The acids are made from cholesterol and are carried out through the body as waste. The flushing away of the bile acids means there is less dietary cholesterol in your body.
Two Types of Oatmeal
There is a difference between instant oatmeal and regular oatmeal. Both products contain the same beta glucan and the same amount of fiber, says Donna Feldman, a contributing expert at TheDietChannel.com. But you will get less fiber with instant oatmeal because regular oatmeal has more oats. Most single packets of oatmeal have 3 g fiber, but a serving of regular oatmeal has 4 g fiber. The single packet of instant contains fewer oats that the 1/2 cup dry oats in a box of regular oatmeal. Instant oatmeal is often flavored with added sweeteners to add more calories when it would be better to add fiber-packed fruits over plain oatmeal.
Artery Walls
Oatmeal has many other health benefits, but research of those benefits has also turned up another plus for beating cholesterol, according to researchers at the U.S. Department of Agriculture (USDA) Human Nutrition Research Center on Aging at Tufts University in Boston, Mass. Oat compounds called "avenanthramides" act to suppress plaque build-up by relaxing artery walls and increasing the space to allow better blood flow, it was reported by the USDA Agricultural Research Service in 2004. Scientists purified the compounds from oats and exposed them to human arterial wall cells for 24 hours. There was significant reduction in the sticking of blood cells to the arterial cells. The action by the oat compounds cuts down on the risks of high cholesterol.
