Alpha-Linolenic Acid (ALA)

Alpha-linolenic acid (ALA) is an essential fatty acid that comes from plants. It is considered an essential nutrient, which means that your body requires it.

ALA is used as a source of energy by the body. It also serves as the parent substance to omega-3 fatty acids, compounds that regulate blood pressure, blood clotting, heart rate, blood vessel dilation, the immune response, and breakdown of fats. Essential fatty acids are also used to make brain and nervous tissue. Only certain plant products provide ALA. Primarily, they are canola (rapeseed), flaxseed (linseed), and soybean oil. Some fish (for example, mackerel and salmon) contain 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. Americans' high consumption of omega-6 oils (corn, safflower, sunflower oils), low intake of fish, and focus on decreasing overall fat in the diet are the primary reasons for inadequate or imbalanced levels of omega-3 fatty acids in the diet. Taking in more omega-6 than omega-3 fatty acids may encourage 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.

Uses

Omega-3 fatty acids have several proven benefits. They are especially good for your heart, they can provide relief from rheumatoid arthritis, they may be helpful in treating multiple sclerosis and some cases of diabetes, and they may help prevent cancer. Recently, omega-3 fatty acids were shown to help treat migraines and depression. ALA may be useful in treating skin cancer.

ALA and other omega-3 oils are used to help treat the following.

• Heart disease: ALA may reduce the risk of heart disease by improving the arteries that carry blood throughout the body and to the brain, and by lowering cholesterol and triglyceride levels.
• Hypertension (high blood pressure)
• Allergic and inflammatory conditions such as psoriasis and eczema
• Autoimmune diseases, such as multiple sclerosis, lupus, and cancer

Dietary Sources

The following foods are good sources of ALA: flax seeds, flaxseed oil, canola (rapeseed) oil, soybean oil, margarine, if made from canola or soybean oil, pumpkin, and walnuts.

Other Forms

There are two types of commercial preparations. Cooking oils (canola oil, soybean oil, margarines made from these oils), and medicinal oils (flaxseed oil, gelatin capsules of flaxseed oil).

Several manufacturing methods can destroy the nutrient value of products that contain ALA. Preferred methods are "modified atmospheric packing methods." Generally, high-quality oil will be certified as organic by a reputable company, bottled in light-resistant containers, refrigerated, and marked with an expiration date.

How to Take It

There is no recommended dietary allowance (RDA) for ALA.

A healthy diet should include less saturated fats and more polyunsaturated essential fatty acids. Discuss your total fat intake with your health care provider if you are thinking about taking ALA supplements.

Precautions

You should talk with your health care provider about your regular diet. Your health care provider can help you decide if you should take supplements, and what kind of supplements may be best for you. Remember that ALA supplements are fats, and are high in calories. Avoid products containing hydrogenated fats.

Possible Interactions

Flaxseed, which contains alpha-linolenic acid, 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.

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