Plant-based foods, such as fruits, grains and vegetables, contain varying types and amounts of complex carbohydrates, known as fiber. As these foods travel through your gastrointestinal tract, your normal digestive processes that breaks the nutrients down into separate components. The sugar, vitamins and minerals from the food travel through the intestinal walls and into your bloodstream. The plant fiber, however, lingers in your intestines to serve a variety of functions, including cholesterol control.
Soluble Fiber
Soluble fiber from plant foods, such as oats, beans, peas, apples, pears, citrus fruits, blueberries, strawberries, barley, psyllium and flaxseeds, dissolves in water within your bowels and then binds with bile acids from your liver to create a gel-like substance that's eventually removed in your stools. As it binds with bile acids, the soluble fiber triggers a chain of events that affects your blood cholesterol level.
Effects of Soluble Fiber
After some of the free bile acids within your intestines bind with soluble fiber, your liver identifies the need for more bile acids to break down your next snack or meal. The liver uses some of its stored cholesterol to create and release new bile acids, and then pulls some of the excess low-density lipoprotein, or "bad cholesterol," from your bloodstream to replace its cholesterol deposits.
Significance
A diet rich in soluble fiber and low in saturated fat, combined with regular physical activity, helps you achieve and maintain healthy levels of both LDL and total cholesterol. You're less likely to develop the plaques of atherosclerosis on the walls of your coronary and carotid arteries when LDL levels are low. Healthier, free-flowing arteries keep your blood pressure under good control, lower your risk of developing coronary heart disease and help prevent strokes and heart attacks.
Misconceptions
Insoluble dietary fiber provides bulk and softness to your stools, but does not lower your blood cholesterol the way soluble fiber does. Most of the fiber from whole grains, nuts, dark green leafy plants and gas-producing vegetables, such as cabbage and brussels sprouts, is insoluble fiber. Eat an array of fruits, vegetables and whole grains to boost your overall fiber intake, but make sure you choose plenty of fruits, nuts and seeds high in soluble fiber as part of your regular meals and snacks.
