Flaxseed oil is rich in a type of fat called alpha-linolenic acid (ALA), an essential fatty acid used as a source of energy by the body. It also serves as the parent substance to compounds that regulate blood pressure, blood clotting, heart rate, blood vessel dilation, the immune response, and the breakdown of fats. Essential fatty acids are also used to make brain and nerve tissue.

ALA is a member of a family of fats called omega-3 fatty acids. Flaxseed oil and fish oils are the richest sources of omega-3 fatty acids. Canola oil and soybean oils also contain some omega-3 fatty acids. Corn, safflower, cottonseed, sesame, and sunflower oils are rich in fats called omega-6 fatty acids. These two families of fats have very important, but different, roles in the body. It is important to have a balance of omega-6 and omega-3 fatty acids in the diet. Excessive intake of either type of fat can cause health problems.

American diets are typically high in omega-6 fatty acids and low in omega-3 fatty acids. Taking in more omega-6 than omega-3 fatty acids through your diet may cause your body to produce substances that cause inflammation and negatively affect your body's response to disease. These imbalances may make you more susceptible to heart disease, inflammatory conditions such as arthritis and psoriasis, and infections, and can lower your immunity. You may gain significant health benefits by increasing the level of omega-3 fatty acids in your diet. This is especially true if you take in large amounts of omega-6 fatty acids.

Here is a partial list of illnesses that may be prevented or treated with flaxseed oil:

• Skin disorders. Flaxseed oil may reduce the itching, swelling, and redness associated with certain skin disorders such as psoriasis, acne, and eczema.
• Hypertension. One tablespoon of flaxseed oil per day appears to be effective in lowering blood pressure.
• Heart disease. ALA may reduce the risk of heart disease by improving the function and integrity of arteries that carry blood throughout the body and to the brain. High doses of ALA may reduce blood cholesterol and triglyceride levels.
• Autoimmune disorders. These disorders, such as rheumatoid arthritis, cause immune cells to attack healthy tissue in the body. Flaxseed oil is converted to a substance in the body that can inhibit this autoimmune reaction.

Preliminary evidence from animal studies also suggests that flaxseed and flaxseed oils may slow the growth of colon tumor cells. Further studies are needed to determine whether flaxseed offers such protective effects against colorectal cancer in humans, however.

Flaxseed oil is found in flaxseed or flaxseed meal. Flaxseed oil is the richest source of omega-3 fatty acids, containing approximately 55 to 65 percent of the essential fatty acid ALA. It also contains the natural antioxidants beta-carotene (vitamin A) and carotenoids.

Flaxseed oil is available in liquid and softgel capsule form, and, like any oil, should be refrigerated to prevent it from becoming rancid. Flaxseed oil requires special packaging because it is easily destroyed by heat, light, and oxygen. The highest quality flaxseed products are manufactured using fresh pressed seeds, are bottled in dark or opaque containers, and processed at low temperatures in the absence of light, extreme heat, or oxygen.

The dosage to prevent and treat disease will vary depending on the amount of fatty acids in the diet, how much ALA an individual's body will convert to EPA, and the type of disorder being treated.

Note: All forms of flax should be stored in a cool, dry place (e.g., refrigerator) once they are opened.

Pediatric

As with all dietary supplements, check with a health care provider before giving flaxseed oil to a child.

Flaxseed oil may be added to a child's diet to help balance fats. If an infant is breastfed, the mother may ingest oil or fresh ground seed to increase fat content in breast milk. See adult dosage below.

Children (2 to 12 years): 1 tsp of ground flaxseeds or 1 tsp of fresh flaxseed oil for constipation

Adult

As a starting dose, 1 tbsp liquid flaxseed oil per day, or 3,000 mg (capsules) bid, is generally recommended.

Flaxseed oil will add additional calories and fat to your diet unless you reduce your intake of other fats.

Flaxseed may slow down the absorption of oral medications or other nutrients if taken at the same time. Talk to your health care provider before taking flaxseed if you regularly take any prescription or over-the-counter medications.

No noteworthy interactions (positive or negative) between flaxseed and conventional medications are known to have been reported in the literature to date. Please refer to the monograph on alpha-linolenic acid (ALA) for additional information regarding that fatty acid.

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