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Alpha-linolenic acid, or ALA, is an essential fatty acid, which means that it
is essential to human health but cannot be manufactured by the body. For this
reason, ALA must be obtained from food. ALA, as well as the fatty acids
eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), belongs to a group
of fatty acids called omega-3 fatty acids. EPA and DHA are found primarily in
fish while ALA is highly concentrated in certain plant oils such as flaxseed oil
and to a lesser extent, canola, soy, perilla, and walnut oils. ALA is also found
in wild plants such as purslane. Once ingested, the body converts ALA to EPA and
DHA, the two types of omega-3 fatty acids more readily used by the body.
It is important to maintain an appropriate balance of omega-3 and omega-6
(another essential fatty acid) in the diet as these two substances work together
to promote health. These essential fats are both examples of polyunsaturated
fatty acids, or PUFAs. Omega-3 fatty acids help reduce inflammation and most
omega-6 fatty acids tend to promote inflammation. An inappropriate balance of
these essential fatty acids contributes to the development of disease while a
proper balance helps maintain and even improve health. A healthy diet should
consist of roughly two to four times more omega-6 fatty acids than omega-3 fatty
acids. The typical American diet tends to contain 11 to 30 times more omega-6
fatty acids than omega-3 fatty acids and many researchers believe this imbalance
is a significant factor in the rising rate of inflammatory disorders in the
United States.
Omega-3 fatty acids have been shown to reduce inflammation and help prevent
certain chronic diseases such as heart disease and arthritis. These essential
fatty acids are highly concentrated in the brain and appear to be particularly
important for cognitive and behavioral function as well as normal growth and
development.
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Studies suggest that ALA and other omega-3 fatty acids may be helpful in
treating a variety of conditions. The evidence is strongest for heart disease
and problems that contribute to heart disease, but the range of possible uses
for ALA include:
Alpha-linolenic Acid for Heart Disease
One of the best ways to help prevent and treat heart disease is to eat a low-fat
diet and to replace foods rich in saturated and trans-fat with those that are
rich in monounsaturated and polyunsaturated fats (particularly omega-3 fatty
acids). In addition to reducing risk factors for heart disease, namely high
blood pressure and elevated cholesterol, evidence suggests that people who eat
an ALA-rich diet are less likely to suffer a fatal heart attack.
Alpha-linolenic Acid for High Cholesterol
People who follow a Mediterranean-style diet tend to have higher HDL ("good")
cholesterol levels. This diet consists of a healthy balance between omega-3 and
omega-6 fatty acids. It emphasizes whole grains, root and green vegetables,
daily intake of fruit, fish and poultry, olive and canola oils, and ALA (found
in flaxseed oil), along with discouragement of ingestion of red meat and total
avoidance of butter and cream. In addition, walnuts (which are rich in ALA) have
been shown to lower cholesterol and triglycerides in people with high
cholesterol.
Alpha-linolenic Acid for High Blood Pressure
Several studies suggest that diets and/or supplements rich in omega-3 fatty
acids (including ALA) lower blood pressure significantly in people with
hypertension. Fish high in mercury (such as tuna) should be avoided, however,
because they may increase blood pressure.
Alpha-linolenic Acid for Acne
Although there are few studies to support the use of omega-3 fatty acids for
skin problems, many clinicians believe that flaxseed is helpful for treating
acne.
Alpha-linolenic Acid for Arthritis
Several studies suggest that omega-3 fatty acid supplements reduce tenderness in
joints, decrease morning stiffness, and improve mobility. Many people who take
these supplements report that they do not need as much medicine to relieve their
painful symptoms.
Alpha-linolenic Acid for Asthma
Preliminary research suggests that omega-3 fatty acid supplements (particularly
perilla seed oil which is rich in ALA) may decrease inflammation and improve
lung function in adults with asthma.
Alpha-linolenic Acid for Eating Disorders
Studies suggest that men and women with anorexia nervosa have lower than optimal
levels of polyunsaturated fatty acids (including ALA and GLA). To prevent the
complications associated with essential fatty acid deficiencies, some experts
recommend that treatment programs for anorexia nervosa include PUFA-rich foods
or supplements.
Alpha-linolenic Acid for Breast Cancer
Women who regularly consume foods rich in omega-3 fatty acids over many years
may be less likely to develop breast cancer and to die from the disease than
women who do not follow such a diet. This is particularly true among women who
consume fish instead of meat. Laboratory and animal studies indicate that
omega-3 fatty acids can inhibit the growth of human breast cancer cells and may
even prevent the spread of cancer to other parts of the body. Several experts
speculate that omega-3 fatty acids, in combination with other nutrients (namely,
vitamin C, vitamin E, beta-carotene,
selenium, and coenzyme Q10), may prove to
be of particular value for preventing and treating breast cancer.
Alpha-linolenic Acid for Burns
Essential fatty acids have been used to reduce inflammation and promote wound
healing in burn victims. Animal research indicates that omega-3 fatty acids help
promote a healthy balance of proteins in the body -- protein balance is
important for recovery after sustaining a burn. Further research is necessary to
determine if this may apply to people as well.
Alpha-linolenic Acid for Inflammatory Bowel Disease (IBD)
Some people with Crohn's disease (CD), one form of IBD, have low levels of
omega-3 fatty acids in their bodies. Evidence suggests that fish oil supplements
containing omega-3 fatty acids may reduce symptoms of CD and ulcerative colitis
(another inflammatory bowel disease), particularly if used in addition to
medication. Preliminary animal studies have found that ALA may actually be more
effective than EPA and DHA found in fish oil supplements, but further studies in
humans are needed to confirm these findings.
Alpha-linolenic Acid for depression
People who do not get enough omega-3 fatty acids or do not maintain a healthy
balance of omega-3 to omega-6 fatty acids in their diet may be at an increased
risk for depression. The omega-3 fatty acids are important components of nerve
cell membranes. They help nerve cells communicate with each other, which is an
essential step in maintaining good mental health.
Alpha-linolenic Acid for Menstrual Pain
In a study of nearly 200 Danish women, those with the highest dietary intake of
omega-3 fatty acids had the mildest symptoms during menstruation.
Other - Alpha-linolenic Acid for ADHD
Although further research is needed, preliminary evidence suggests that omega-3
fatty acids may also prove helpful in protecting against certain infections and
in treating a variety of conditions including ulcers, migraine headaches,
attention deficit/hyperactivity disorder (ADHD), preterm labor, emphysema,
psoriasis, glaucoma, Lyme disease, and panic attacks.
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Dietary sources of ALA include flaxseeds, flaxseed oil, canola (rapeseed)
oil, soybeans and soybean oil, pumpkin seeds and pumpkin seed oil, purslane,
perilla seed oil, walnuts and walnut oil.
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There are two types of commercial ALA preparations: cooking oils (including
canola oil and soybean oil) and medicinal oils (including flaxseed oil and
dietary supplements containing flaxseed oil).
Some manufacturing methods can destroy the nutrient value of products that
contain ALA by exposing these oil-rich products to air, heat, or light.
Generally, high-quality oil is bottled in light-resistant containers,
refrigerated, and marked with an expiration date. All sources of omega-3 fatty
acids are best kept refrigerated to protect the quality of the oil.
Be sure to buy ALA supplements made by established companies who certify that
their products are free of heavy metals such as mercury.
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How to Take ALA
The recommended adequate intake of ALA in the diet is listed below:
Pediatric
- Infants that are breastfed should receive sufficient amounts of ALA if
the mother has an adequate intake of this fatty acid.
- Infant formula should contain 1.5% ALA.
Adult
(100 grams of raw flaxseed provides 22,800 mg of ALA; 100 grams of dried
butternuts provides 8,700 mg of ALA; 100 grams of English and Persian walnuts
provides 6800 mg of ALA; 100 grams of cooked soybeans provides 2,100 mg of ALA)
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Because of the potential for side effects and interactions with medications,
dietary supplements should be taken only under the supervision of a
knowledgeable healthcare provider.
People with either diabetes or
schizophrenia may lack the ability to convert
ALA to EPA and DHA, the forms more readily used in the body. Therefore, people
with these conditions should obtain their omega-3 fatty acids from dietary
sources rich in EPA and DHA.
Although studies have found that regular consumption of fish (which includes
the omega-3 fatty acids EPA and DHA) may reduce the risk of macular
degeneration, a recent study including two large groups of men and women found
that diets rich in ALA may substantially increase the risk of this disease. More
research is needed in this area. Until this information becomes available, it is
best for people with macular degeneration to obtain omega-3 fatty acids from
sources of EPA and DHA, rather than ALA.
Similar to macular degeneration, fish and fish oil may protect against
prostate cancer, but ALA may be associated with increased risk of prostate
cancer in men. More research in this area is needed.
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If you are currently being treated with any of the following medications, you
should not use ALA without first talking to your healthcare provider.
Blood-thinning Medications
Omega-3 fatty acids may increase the blood-thinning effects of warfarin,
aspirin, or other blood-thinning medications. While the combination of aspirin
and omega-3 fatty acids may actually be helpful under certain circumstances
(such as heart disease), they should only be taken together under the guidance
and supervision of your healthcare provider.
Cholesterol-lowering Medications
Following certain nutritional guidelines, including increasing the amount of
omega-3 fatty acids in your diet and reducing the
omega-6 to omega-3 ratio, may
allow a group of cholesterol lowering medications known as "statins" (such as
atorvastatin, lovastatin, and simvastatin) to work more effectively.
Cyclosporine
Taking omega-3 fatty acids during cyclosporine therapy may reduce toxic side
effects (such as high blood pressure and kidney damage) associated with this
medication in transplant patients.
Nonsteroidal Anti-inflammatory Drugs (NSAIDs)
In an animal study, treatment with omega-3 fatty acids reduced the risk of
ulcers from nonsteroidal anti-inflammatory drugs (NSAIDs). More research is
needed to evaluate whether omega-3 fatty acids would have the same effects in
people.
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list of all supplements, vitamins
Reviewed: 01/2006
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