Adequate fiber intake is a necessary part of a healthy diet. There are a number of reasons why fiber is considered healthy, not the least of which is, its proven track record of reducing the risk of heart disease.
What Is Soluble and Insoluble Fiber?
Fiber, or dietary fiber, is the indigestible parts of plant foods. With that in mind, the human body is not capable of processing fiber completely. One might think that if our bodies cannot process something, what benefit could we receive from consuming it?
Fiber is more important for the secondary effects that is has on our digestive system. Depending on the kind of fiber, it can have different beneficial effects. There are two types of fiber: soluble fiber and insoluble fiber. In the colon, soluble fiber is readily fermented into gases and chemically beneficial byproducts. Insoluble fiber absorbs water as it makes its way through the digestive system.
Dietary fiber is found in all plant foods including fruits and vegetables. Some provide more than others though. Most sources contain both soluble and insoluble fiber but may have more of one than the other. Legumes, such as beans, peas and lentils, contain some of the highest concentration of fiber. Fruits, such as prunes and raspberries, and grains are also excellent sources.
Benefits of Fiber: Insoluble and Soluble
Insoluble fiber’s main benefit is that it eases defecation. By absorbing water, it bulks up stool and makes it easier for it to pass, thus correcting incidences of constipation. The ultimate result is greater regularity of bowel movements.
Soluble fiber is a bit more complex but is still beneficial nonetheless. It too can absorb water but it also traps carbohydrates in the process. The result is a reduction in spikes of blood sugar levels and regulation of blood glucose levels in general, which diabetics and those at risk should take note of. Also, insoluble fiber reacts chemically in the colon to produce short-chain fatty acids that may reduce the risk of colorectal cancer.
Fiber and Heart Health
What about the lowered risk of heart disease? If the above reasons aren’t enough to include more fiber into your diet, consider that soluble fiber has proven to lower levels of LDL cholesterol in your body. It does this by binding with bile in your intestines. Once they’re bound, the bile is excreted and removed from your system. With less bile in your system, your liver will increase production of bile salts, which require LDL cholesterol as an ingredient. The liver will increase LDL receptors to gather the LDL cholesterol it needs for the task, thus reducing free LDL cholesterol in general in your body. LDL cholesterol is indicated in increased incidences of heart disease, so less of it in your system lowers your risk.
Studies have shown that increasing soluble fiber intake by 5 to 10 grams a day is enough to lower LDL cholesterol by 5%. Increasing intake beyond that is even more beneficial. Oat bran, wheat bran and carrots have some of the highest concentration of insoluble fiber.
If you want to reduce the risk of heart disease, include more fiber in your diet, especially insoluble fiber.