What is the difference between soluble and insoluble dietary fiber?

Ozgen Dogan
Cardiology (Cardiovascular Disease)
There are two types of fiber: soluble fiber and insoluble fiber. Soluble fiber dissolves in water and is found in beans, peas, the fleshy part of fruits and oatmeal. Insoluble fiber does not dissolve in water and is found in raw vegetables, the skins of fruit, wheat, bran, brown rice and the outer shells of beans, seeds and nuts. While both are crucial for good health, soluble fiber has the added distinction of reducing low-density lipoprotein (LDL) cholesterol levels.
Soluble dietary fiber dissolves in water, while insoluble dietary fiber does not.

Both types of fiber are important because they resist digestion and help feel naturally full, decreasing your hunger and intake of food and helping you keep weight and body fat down.

Insoluble fiber has no direct effect on your heart, although it does assist in controlling weight and regulating insulin-which indirectly help the heart immensely.

Soluble fiber, on the other hand, has a more direct, beneficial impact on heart health.

The soluble fiber in carrots and other foods helps to lower bad cholesterol, which, in turn, helps to keep the arteries clean. Bad cholesterol, also known as LDL, helps plaque form in the arteries which narrows passageways and restricts blood flow to the heart.

In essence, soluble fiber helps to reduce the formation of micelles, a molecule cluster which is needed to absorb cholesterol. If micelle formation is reduced, our body absorbs less cholesterol.

If you eat the daily recommended amount of fiber, you could reduce your cholesterol by up to 20 percent.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.