Flaxseed Benefits and Use

The nation’s interest in flaxseed has exploded in recent years as flaxseed is thought to have many beneficial effects on the body. Flaxseed is the seed from the Linum usitatissimum plant, and the seed and seed oil are used as food as well as in many medications.  Common food products that contain flaxseed include crackers and oatmeal. Flaxseed contains protein and offers many nutritional and health benefits. The main three nutritional benefits of flaxseed are:

• Omega-3 Fatty Acids. Flaxseed contains alpha-linoleic acid, an omega-3 fatty acid. These fatty acids are considered “healthy fats,” and can help improve heart health, lower triglyceride levels, and aid in the treatment of inflammatory bowel disease and arthritis. One tablespoon of ground flaxseed has around 1.8 grams of omega-3.
• Lignans. Lignans are compounds with phytoestrogenic properties. These properties allow lignans to help lower blood cholesterol and to treat atherosclerosis. Lignans in flaxseed have been shown to reduce total cholesterol levels and LDL (bad cholesterol) levels in the blood. However, flaxseed does not appear to improve HDL (good cholesterol) levels. Lignans also have antioxidant properties which help protect the body’s cells from harmful compounds called free radicals. Flaxseed may contain as much as 800 times more lignans than most other plant foods.
• Fiber. Flaxseed contains both soluble and insoluble fibers. Fiber is an important part of digestive health, weight maintenance, and blood cholesterol control. Fiber from flaxseed may help manage constipation, diarrhea, irritable bowel syndrome (IBS) or irritable colon, diverticulitis (inflammation of the lining in the large intestine), ulcerative colitis (ulcers in the large intestine lining), gastritis (inflammation of the stomach lining), and enteritis (inflammation of the small intestine). Although flaxseed may help with the above conditions, it is not advised for all. If taken without sufficient water, flaxseed can cause constipation or even a bowel obstruction Most of the fiber found in flaxseed is located in the seed coat, so consuming flaxseed oil will not provide a significant amount of fiber.

In addition to the wonderful benefits discussed above, research indicates that flaxseed may play a protective role against cancer including breast cancer, prostate cancer, and colon cancer. Flaxseed may lower blood glucose and A1C levels in some individuals, which is important for diabetes management. However, it is important that diabetes patients monitor their blood glucose closely when they supplement with flaxseed as their blood glucose can drop too low. Flaxseed is also thought to protect against cardiovascular disease. Additionally, flaxseed may be effective in managing mild menopausal symptoms. Taking 40 mg of flaxseed by mouth each day reportedly reduces the frequency of hot flashes and night sweats in menopausal women.  

Flaxseed can be purchased in multiple forms, including flax (or flaxseed) oil, flax meal (ground flaxseed), and whole flaxseed. Flaxseed oil should be kept refrigerated. To get the most nutritional benefit, consume flaxseed within 24 hours of grinding. Flaxseed can easily be incorporated into many foods such as baked goods, dark meats, oatmeal, and smoothies. Before supplementing your diet with flaxseed, consult your doctor. Until more information is known about flaxseed, pregnant and lactating women are not encouraged to supplement their diet with flaxseed. Furthermore, because flaxseed can slow down the blood clotting process, individuals with bleeding disorders should not use flaxseed supplements.

Submitted by:

Jennifer Heidel, MS, RD Eligible

Sources

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