Does Flaxseed Contain Soluble or Insoluble Fiber?

Fact Checked

iAnetlanda/iStock/Getty Images

Flaxseed is the name given to the seeds of the plant Linum usitatissimum. Flaxseeds contain several beneficial components, including high levels of fiber, omega-3 fatty acids and lignans. Many health conditions, including constipation, irritable bowel syndrome and atherosclerosis, are sometimes treated with flaxseeds. Similar to other health supplements, ask your doctor before consuming large amounts of flaxseeds to treat a disease.

Fiber in Flaxseeds

The term fiber refers to a large group of materials, often from plants, that cannot be digested by the human body. Fiber can be classified into two types, soluble and insoluble, which behave differently inside the human body. Flaxseeds, like many plants, contain high levels of both soluble and insoluble fiber, explains Jack Carter, Professor Emeritus in the Department of Plant Sciences at North Dakota State University.

Benefits of Soluble Fiber

Soluble and insoluble fiber have different effects on the human body. Soluble fiber derives its name from the fact that it dissolves in water, turning into a thick, viscous gel-like substance. When soluble fiber dissolves in water inside the small intestine, it tends to slow down digestion. Soluble fiber also can bind to cholesterol, preventing it from being absorbed by the body and reducing cholesterol levels, explains the Linus Pauling Institute at Oregon State University.

Benefits of Insoluble Fiber

In contrast to soluble fiber, insoluble fiber does not dissolve in water. Because insoluble fiber does not turn into a gel-like substance in the intestines and it cannot be absorbed by the intestines, it tends to pass quickly through the digestive system, MedlinePlus explains. Insoluble fiber can also help increase the passage of other foods through the digestive tract, resulting in increased bowel movements and less constipation.

Other Benefits of Flaxseeds

In addition to improving digestion and lowering cholesterol, flaxseeds may have a blood-thinning effect. Together with lowering cholesterol, this blood-thinning effect of flaxseeds may reduce atherosclerosis, or hardening of the arteries. Flaxseeds also contain compounds known as lignans, which are very similar in structure to estrogen. The lignans in flaxseed may compete with estrogen in biochemical reactions within the body and lower the activity of estrogen, which may reduce the spread of some cancers, according to MedlinePlus. Additional research is needed to confirm these health benefits of flaxseeds.