GLA
What Is It?
Considered to be one of the "good" fats, GLA, or gamma-linolenic acid, is an inflammation-fighter that may be beneficial for conditions ranging from menstrual problems and skin rashes to rheumatoid arthritis and diabetes. It is found in the oils of various plants. Particularly good sources are the seeds of the hardy borage plant (Borago officinalis), the yellow-blossomed evening primrose (Oenothera biennis), and the deciduous Eurasian black currant shrub (Ribes nigrum).
Ordinarily, the body produces plentiful GLA from a compound called linoleic acid, an "essential" fatty acid that the body cannot produce itself but which is readily obtained from dietary sources such as corn, sunflower, soy, peanut, and other food oils. However, with a poor diet, advancing age, or illness, it's often beneficial to get extra GLA in supplement form to make up for possible linoleic acid deficits.
In recent years, scientists have come to recognize the damaging role of inflammation in Alzheimer's disease, heart disease, and a host of other illnesses. GLA may help these conditions by quelling the inflammatory process. The body converts GLA into prostaglandins, hormonelike compounds that help to regulate inflammation, blood pressure, and many other bodily processes. That may be one reason why GLA can be beneficial for such a wide range of ailments.
In addition, GLA is chemically known as an omega-6 fatty acid. It competes with another group of fatty acids, called omega-3s (the heart-healthy oils found in fish and flaxseed oil) for certain enzymes during digestion. Experts contend that the Western diet has become too high in omega-6 oils at the expense of omega-3s. These sources suggest that this imbalance may play a role in the rising incidence of chronic illnesses such as cancer and heart disease. It's not unusual for Americans today to take in 10 times or more omega-6s, in the form of fatty snacks, packaged goods, and fast foods, than omega-3s. A healthy ratio is thought to be 3:1, or 3 grams of omega-6s for every gram of omega-3s.
Health Benefits
GLA may have benefits for soothing breast tenderness, inflammatory arthritis, and many other complaints. In many studies, GLA-rich evening primrose oil capsules were used, although GLA from borage or black currant oils may also help.
In addition to the conditions cited below, GLA has been proposed as a treatment for allergies, bursitis, high cholesterol, prostate disease, irritable bowel syndrome, chronic fatigue, impotence, infertility, gout, kidney stones, weight loss, and myriad other ailments.
Some preliminary studies indicate that GLA may benefit lupus and Huntington's chorea. One study found evidence that GLA boosts the effectiveness of tamoxifen, a hormone used to treat breast cancer; women undergoing cancer treatment should never use GLA without consulting their doctor, however. When combined with fish oils, GLA may even boost the benefits of calcium in promoting bone health and preventing osteoporosis.
Specifically, GLA may help to:
• Relieve breast pain and other symptoms of premenstrual syndrome (PMS). GLA appears to benefit about half of women with the painful menstrual-related condition known as fibrocystic breasts. By helping to stabilize hormone levels and reduce inflammation, it抯 possible that GLA will also ease bloating, cramping, and other PMS discomforts. GLA may similarly ease perimenopausal symptoms.
• Treat eczema, itchy skin, and acne. In some studies, eczema sufferers who took GLA had fewer scaly skin eruptions and were able to reduce their use of potent anti-inflammatory steroid drugs. Some experts have proposed GLA for psoriasis, acne, and the common ruddy-faced symptoms of rosacea. Some even recommend it for the skin itching that can result from kidney dialysis.
• Prevent the nerve pain of diabetes. In Europe, GLA is commonly used to treat the burning, numbness, pain, and tingling in the feet or hands caused by diabetes-related nerve damage. In one study, people with mild diabetes-related nerve pain who took evening primrose oil for a year felt better than those taking a placebo.
• Ease the aches of rheumatoid arthritis. At very high doses (up to 1.4 grams per day or more), GLA reduces the pain and swollen joints of the inflammatory immune disease rheumatoid arthritis. It may be especially effective when combined with conventional treatments. Benefits may accumulate with time.
• Manage attention deficit hyperactivity disorder (ADHD), Alzheimer's, and multiple sclerosis. Essential fatty acids like those found in GLA and fish oils are necessary for the health and proper functioning of the nervous system. In some studies, GLA supplements reduced behavioral and learning problems in children with ADHD, although not always as well as a standard stimulant drug. Nutritionally oriented physicians also sometimes recommend GLA for Alzheimer's disease and multiple sclerosis.
• Control ulcerative colitis. A small but rigorous trial found that people with ulcerative colitis, an inflammatory bowel disease, may benefit from evening primrose oil. However, another study found that taking GLA along with fish oils did not help to induce remissions of the disease. More research is clearly needed.
• Alleviate Raynaud's phenomenon. Many people, particularly women, suffer from a persistent feeling of coldness in the fingertips and toes called Raynaud's disease. One study found that gently rubbing GLA-dense oils directly onto the fingertips eased symptoms of this mysterious circulatory illness.
• Nourish nails, scalp, and hair. The rich stores of essential fatty acids in evening primrose and borage oils not only prevent nails from cracking but can also enrich and moisturize the scalp and hair, making GLA potentially useful for treating dandruff, itchy scalp, and dry hair.
Dosage Information
Special tips:
--The primary sources of GLA are evening primrose oil, borage oil, and black currant oil. Evening primrose oil (EPO), the most commonly used form, contains from about 7% to 10% GLA. For a 240 mg dose of GLA, you would need to take about three tablespoons (3,000 mg) of EPO.
--Ounce for ounce, a more economical choice is usually borage oil, which contains 20% to 26% of the fatty acid. One tablespoon (1,000 mg) provides 240 mg of GLA.
--Black currant oil contains 14% to 19% GLA, so one to two tablespoons (1,500 mg) provides an equivalent 240 mg dose of the fatty acid. Black currant oil is also rich in the heart-healthy omega-3s DHA and EPA.
• For most of the ailments mentioned: 240 mg of GLA daily (1 tablespoon of borage oil, 3 tablespoons of evening primrose oil, or 1 to 2 tablespoons of black currant oil).
• For the nerve pain of diabetes: 240 mg of GLA daily, along with 1,000 mg of fish oils twice a day.
• For Raynaud's disease: Take 240 mg of GLA orally daily. Alternatively, apply one or two capsules of evening primrose oil, borage oil, or black currant oil to the affected area of skin every day.
Guidelines for Use
• Don't expect immediate results. Effects may take six months or longer to be felt.
• The oils can be mixed into juice or a fruit smoothie, or added to salad dressing. Some people find it easiest (and most effective) when taken in two or three divided doses throughout the day.
• Take with food to enhance absorption of GLA. Food also minimizes the likelihood of digestive upset.
• Like other polyunsaturated fats, evening primrose and borage oils are easily oxidized and can spoil when exposed to heat, light, and oxygen. Even softgels, which are designed to prevent oxidation, can turn rancid. Store in a cool, dry place away from light. Some products add vitamin E to help prevent oxidation, although this is no guarantee of freshness. Spoiled products often taste, smell, or feel funny or "off" and are more likely to cause digestive upset.
• Do not cook with GLA oils. They will break down and become ineffective if exposed to high heat.
• Watch out for "complex blends" or "formulas" that contain a mix of oils. Some commercial products include cheap substitutes such as soy or safflower oils that do not contain GLA or provide only a low dose.
General Interaction
• If you take an anticoagulant (blood thinning) medication such as warfarin, check with your doctor before taking GLA. It may impair the ability of your blood to clot.
• There are no other known food or nutrient interactions associated with GLA.
Note: For information on interactions with specific generic drugs, see our WholeHealthMD Drug/Nutrient Interactions Chart.
Possible Side Effects
• GLA appears to be very safe. Thousands of people have taken evening primrose oil and other forms of GLA in medical studies, sometimes at very high doses. No serious adverse reactions or side effects have been reported.
• Nausea, diarrhea, and mild digestive upset can occur with GLA oils, especially when you first begin taking them. If gastrointestinal discomforts develop, try reducing the dose and make sure your products are fresh.
Cautions
• If you have epilepsy or seizures, use GLA with caution. Some early reports suggested it could make your condition worse.
• GLA has not been tested extensively in children or in pregnant or nursing mothers. Safety and effectiveness in these groups remain to be determined.
• The leaves and roots of the borage plant contain potentially toxic compounds called pyrrolizidine alkaloids (PAs) that may damage the liver (at high doses over long time-periods especially). Check the label carefully to make sure you are buying oil extracted from the seeds and not the plant, and buy it from a manufacturer you trust.
• Do not exceed recommended doses of borage oil, and avoid teas and herbs made from the whole plant. Periodic check-ups with your doctor are also advised if you are taking borage oil long term.
• If you have liver problems, you may want to opt for evening primrose oil rather than borage oil.
Evening primrose oil
Ailments Dosage
Acne 1,300 mg twice a day; take as alternative to borage oil
Borage oil
Ailments Dosage
Acne 1,000 mg a day (take as alternative to evening primrose oil)
作者:ilqfk
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