encyclopedia

Alpha-Linolenic Acid (ALA)

Natural Sources:    

Flaxseed oil; other seed and nut oils such as pumpkin seed oil, canola oil and soya oil, grass and dark green leafy vegetables, certain marine algae.    
   
  
Forms:    

Oil extracts sold in capsules or bulk form; certified organic culinary oils (expeller-pressed in the absence of light, heat and oxygen).    
 
   
Therapeutic Uses:     

– ADD/ADHD
– Allergies
– Anti-inflammatory
– Antioxidant (indirect)
– Asthma
– Atherosclerosis
– Arthritis
– Autoimmune Diseases
– Behavioral Disorders
– Brain Disorders
– Cancer
– Cardiovascular Disease
– Cellular Regeneration
– Chronic Fatigue Syndrome
– Cleansing
– Depression
– Detoxifying
– Diabetes
– Eczema
– EFA Deficiency
– Endometriosis
– Eyesight Disorders
– Fatigue
– Fibrocystic Breast Disease
– Fibroids
– Fibromyalgia
– Gout
– Heart Health Maintenance
– Hemorrhoids
– Hepatitis
– Hormone Imbalances
– Hypertension
– Infantile Atopic Eczema
– Joint Pain
– Lyme's Disease
– Mastalgia
– Menopausal Problems
– Mood Swings
– Muscle Cramps/Pain
– Nervous Disorders
– Neurological Disorders
– Neuropathy
– Osteoporosis
– PMS
– Pre-ecclampsia
– Pregnancy-related Disorders
– Postpartum Depression
– Postviral Fatigue Syndrome
– Reducing LDL Cholesterol
– Reproductive Organ Health
– Retinal Disorders
– Rheumatoid Arthritis
– Senility/Aging Problems
– Skin Disorders
– Sleep Disorders
– Slow Metabolism
– Stroke
– Tendonitis
– Vascular Disorders
– Vascular Tone     
     
    
Overview:    

Alpha-Linolenic Acid (ALA) is one of two types of essential fats that must be obtained through the diet because, like vitamins, it is essential but can't be produced by the body. There are two fatty acids that are essential for life – linoleic acid (LA) in the omega-6 family and alpha-linolenic acid (ALA) in the omega-3 family. Linoleic acid is readily found in most foods containing fats and oils, however, alpha-linolenic acid is found only in quantity in flaxseed oil and in small amounts in several other nuts and seeds and in dark green leafy vegetables. Flaxseed oil contains approximately 57% alpha linolenic acid and 15% linoleic acid. The human body converts LA and ALA into longer chain fatty acids including arachidonic acid (AA), gamma linolenic acid and docosahexaenoic acid (DHA). The conversion steps between ALA and DHA can be slowed down by many lifestyle factors, including a diet rich in saturated fats and trans-fatty acids, stress, viral infections, too much alcohol or cholesterol and various illnesses. Flaxseed oil can be used to prevent and treat EFA deficiencies in the diet, such as those related to brain and retinal disorders, especially in infants, allergies, high cholesterol, hypertension, cancer, diabetes, skin disorders, and hormonal imbalances. Every cell of the body has a phospholipid membrane made up of essential fatty acids: 60% EFA's for most cells and 80% EFA's for brain and nerve cells. The human retina is fully 60% omega-3's. Omega-3 EFAs are important for membrane fluidity of all cells of the body; they also protect the body against abnormal blood clotting and are anti-inflammatory. Studies have shown that increased levels of omega-3s in the diet increases the flexibility of red blood cells for passing through capillaries and blood vessels within only three days and reduces and/or normalizes blood platelet stickiness.
    
     
Chemistry:    

The most common omega-3 (n-3) fatty acid obtained from food is alpha-linolenic acid (ALA, 18:3 n-3); the most common omega-6 (n-6) is called linoleic acid (LA, 18:2 n-6). These are polyunsaturated fatty acids with an 18 carbon chain length with their first double bond at either the third carbon (n-3) or the sixth carbon (n-6) from the methyl group end. These EFA's must be obtained from foods because the body can not produce them on it's own and they are required as precursors for many biologically essential molecules.    
   
     
Suggested Amount:    

The recommended daily dosage for alpha-linolenic acid ranges from between 5 – 7 grams daily based on traditional diets with noted heart-smart benefits. To obtain this amount from flaxseed oil, it is recommended to take at least one tablespoon of flaxseed oil daily with food. Flaxseed oil can be used as a component of salad dressings, or it can be incorporated into other foods such as non-hydrogenated margarines or butters, or it can be mixed in with fruit smoothies or other shaken drinks. Flaxseed oil should never be used for frying foods, but may be used safely in baked foods. Other sources of ALA include pumpkinseed oil (10%), canola oil (10%), walnut oil (20%), butternuts (8%), wheat germ oil (7%), Persian English walnuts (7%), green soybeans (3%), soya oil (3-6%), roasted soybean kernels (1.5%), Beechnuts (1.7%), oat germ (1.4%) and purslane (1%). Note: For information on long-chain omega-3 fatty acids from fish, see the monograph on Omega-3 Essential Fatty Acids. The above information is from the U.S. Department of Agriculture and can be obtained from the U.S. Nutrient Database on the worldwide web. For more detailed information of foods with EFA levels, see the books Food Your Miracle Medicine and Stop Aging Now by Jean Carper (1993, 1995).    
   
Drug Interactions:    

Omega-3 EFAs, when taken in excessive amounts, can prolong bleeding time and weaken the strength of blood vessels. Do not take omega-3 EFA supplements (in capsule form) while on blood thinners without first consulting with your physician. Stroke victims and persons at risk of having a stroke should also first consult with their physicians prior to using omega-3 EFA supplements.    
     
    
Contraindications:    

Omega-3 EFA supplements (in capsule form) are contraindicated for persons on blood thinners without first consulting with your physician. Stroke victims and persons at risk of having a stroke should also first consult with their physician prior to using omega-3 EFA supplements.    
     
    
Side Effects:    

Taken as directed, omega-3 rich oils do not have any negative side effects. However, excessive flaxseed oil and/or omega-3 EFAs in the diet, in the absence of adequate levels of omega-6 EFAs, can weaken blood vessels and capillaries and increase the tendency and frequency of nose bleeds and other bleeding problems. This increased risk of bleeding with excessive flaxseed oil and/or omega-3 EFAs in the diet can be avoided simply by using EFA balanced flaxseed oil blends containing sunflower and other oils.    
     
   
References:     
     
Allman et al. 1995. Supplementation with flaxseed oil versus sunflower seed oil in healthy young men consuming a low fat diet: effects on platelet composition and function. European J Clin Nutr 49: 169-178
 
Bagga et. al. 1997. Dietary modulation of omega-3/omega-6 polyunsaturated fatty acid rations in patients with breast cancer. J National Cancer Inst. 89(15): 1123-1131.
 
Behan et al. 1990: Effect of high doses of essential fatty acids on the postviral fatigue syndrome. Acta Neurol Scand 82(3): 209-216
 
Belch et al. 1988: Effects of altering dietary essential fatty acids on requirements for non-steroidal anti-inflammatory drugs in patients with rhematoid arthritis: a double blind placebo controlled study. Ann Rheum Dis 47(2): 96-104.
 
Bibus, DM, Stitt, PA and RT Holman 1998. Ratios of Linoleic and Alpha Linolenic Acids in the Diet: Implications in the Health of Humans and Companion Animals. (Hormel Institute and University of Minnesota). Proc. of the 57th Flax Institute of the USA, March 26-28, 1998, Doublewood Inn, Fargo, North Dakota. J.F. Carter, ed. North Dakota State Univ., Fargo, ND pp. 49-58.
 
Billman 1994. Prevention of ischemia-induced ventricular fibrillation by omega-3 fatty acids. Proceedings of the National Academy of Sciences 91: 4427-4430.
 
Briggs, C.J. 1986. Evening Primrose: La Belle de Nuit, the King's Curall. Canadian Pharmaceutical J. 119: (5): 249-254.
 
Brown et al. 1998: Nutrition Supplements and the eye. Eye. 12(Pt1): 127-133 Burr 1989. Effects of changes in fat, fish and fibre intakes on death and myocardial reinfarction: diet and reinfarction trial (Dart). Lancet Sept. 1989: 757-761
 
Carper 1997. Miracle Cures: Dramatic New Scientific Discoveries Revealing the Healing Powers of Herbs, Vitamins and Other Natural Remedies. Published by HarperCollins Publ., Inc., 10 East 53rd Street, NY.
 
Carper, J. 1993. Food Your Miracle Medicine: How Food Can Prevent and Cure Over 100 Symptoms and Problems. Based on more than 10,000 scientific studies.  Published by HarperCollins Publ., Inc., 10 East 53rd Street, NY. Conquer and Holub 1996: Supplementation with Algae Source of Docosahexaenoic Acid Increases (n-3) Fatty Acid Status and Alters Risk Factors for Heart Disease in Vegetarian Subjects. J Nutr 126: 3032-3039
 
Davidson and Liebson  1986: Marine lipids and atherosclerosis: a review. Cardiovascular Reviews & Reports 7: 461-472.
 
Davidson et al. 1997: Effects of Docosahexaenoic acid on Serum Lipoproteins in Patients with Combined Hyperlipidemia: A Randomized, Double-blind, Placebo Controlled Trail. J Am College Nutr 16(3); 236-243
 
Duke, J. A. 1988. Evening Primrose: The Morning After. Let's Live 56 (7): 56-57
 
Duke, J. 1992: Handbook of Phytochemical Constituents of GRAS Herbs and Other Economic Plants. pp. 186-187. CRC Press
 
Erasmus, U. 1993: Fats that Heal, Fats that Kill. Published by Alive Books, Burnaby, B.C., Canada. pp. 1-456.
 
Fiocchi et al. 1994: The efficacy and safety of gamma-linolenic acid in the treatment of infantile atopic dermatitis. J Int Med Res 22(1):24-32
 
Gately et al. 1992: Drug treatments for mastalgia: 17 years experience in the Cardiff Mastalgia Clinic. J R Soc Med 85(1):12-15
 
Griffiths, J. 1990. New Osteoporosis treatment: Progesterone reported to increase bone density 10% in six months. Med. Tribune. 11/29/90. p. 1,8.
 
Haban et al. 1998: The effect of n-3 fatty acid administration on selected indicators of cardiovascular disease risk in patients with type 2 diabetes mellitus. Bratislavske Lekarske Listy 99(1):37-42.
 
Harris 1993. Modification of lipid-related atherosclerosis risk factors by w-3 fatty acid ethyl esters in hypertriglyceridemic patients. J Nutr Biochem 4:706-712
 
Health and Welfare Canada 1990. Nutrition Recommendations. The Report of the Scientific Review Committee. Published by the authority of the Minister of National Health and Welfare. Minister of Supply and Services Canada 1990. Available in Canada through Associated Bookstores and other booksellers or by mail from: Canadian Government Publishing Centre, Supply and Services Canada, Ottawa, Canada, K1A 0S9. Cat. No.: H49-42/1990E; ISBN: 0-660-13417-9.
 
Holm, L.E. 1993. Treatment failure and dietary habits in women with breast cancer. Journal of the National Cancer Institute 85(1): 32-36.
 
Holman 1996. Deficiencies of Essential omega 3 fatty acids in humans are not rare. Proc. 56th Flax Institute of the USA, J.F. Carter, ed. North Dakota State Univ., Fargo, ND pp1-8.
 
Horrobin 1992. Nutritional and Medical Importance of Gamma-linolenic Acid. Prog. Lipid Res.31(2): 163-194
 
Howe, G.E. 1990. Dietary factors and risk of breast cancer: combined analysis of 12 case-control studies. Journal of the National Cancer Institute 82(7): 561-569.
 
Innis and Hansen 1996: Plasma fatty acid responses, metabolic effects, and safety of microalgal and fungal oils rich in arachidonic and docosahexaenoic acids in healthy adults. Am J Clin Nutr 64:159-167;
 
Karmali, R.A. 1989. Omega-3 fatty acids and cancer. Journal of Internal Medicine 225 (suppl. 1): 197-200.
 
Keen et al. 1993: Treatment of diabetic neuropathy with gamma-linolenic acid. The gamma-linolenic acid multicenter trial group. Diabetes-Care 16(1):8-15
 
Kushi, L.H. 1992. Dietary Fat and postmenopausal breast cancer. Journal of the National Cancer Institute 84(14): 1092-99.
 
Lands et al. 1992. Maintenance of lower proportions on (n-6) eicosanoid precursors in phospholipids of human plasma in response to added dietary (n-3) fatty acids. Biochemica et Biophysica Acta 1180: 147-162
 
Lassere et al. 1985Lee, H.P. 1991. Dietary effects on breast-cancer risk in Singapore. Lancet 337:1197-1200.
 
Lee, H.P. 1991. Dietary effects on breast-cancer risk in Singapore. Lancet 337:1197-1200.
 
Lee, J.R. 1991b. Is Natural Progesterone the Missing Link in Osteoporosis Prevention and Treatment. Medical Hypotheses 35, 316-318.
 
Michnovicz, J.J. 1990. Induction of estradiol metabolism by dietary indole-3-carbinol in humans. Journal of the National Cancer Institute 82(11): 947-949.
 
Nobmann et al. 1998: Dietary intakes among Siberian Yupiks of Alaska and implications for cardiovascular disease. Int J Circumpolar Health (Jan 1998) 57(1):2-3
 
Papendorp et al. 1995: Biochemical profile of osteoporotic patients on essential fatty acid supplementation. Nutr Res 15(3): 325-334.
 
Peat, R.F. 1982. Progesterone: Essential to Your Well-Being. Let's Live, April 1982.
 
Reinish, J.M. 1978. The Female Patient, April 1978, p. 87.
 
Rose, D.P. 1991. Effect of dietary fat on human breast cancer growth and lung metastasis in nude mice. Journal of the National Cancer Institute 83(20): 1491-1495.
 
Rousseau et al. 1998: Is a dietary n-3 fatty acid supplement able to influence the cardiac effect of the psychological stress? Mol Cell. Biochem. 178(1-2): 353-366.
 
Siguel 1998. Dietary modulation of omega-3/omega-6 polyunsaturated fatty acid rations in patients with breast cancer. J National Cancer Inst. 90(8): 629-631.
 
Siguel 1996. Diagnosis of Essential Fatty Acid (EFA) Deficiency: Using Flax to Prevent Heart Disease. Proc. 56th Flax Institute of the USA, J.F. Carter, ed. North Dakota State Univ., Fargo, ND pp123-133.
 
Stevens et al. 1996: Omega-3 fatty acids in boys with behaviour, learnin and health problems. Physiol Behav 59(4/5) 915-920;
 
Stevens et al. 1995: Essential fatty acid metabolism in boys with attention deficit hyperactivity disorder. Am J Clin Nutr 62(4): 761-8;
 
Stordy 1995: Benefits of docosahexaenoic acid supplementation to dark adaptation in dyslexics. Lancet 346: 8971, 385.
 
Umemura et al. 1997: Effectiveness of a health education class to increase fish intake evaluated by serum fatty acid compositions. Japanese J Public Health 44(12): 901-9.
 
Weil, A. 1995. Spontaneous Healing. Alfred A. Knopf, New York or Random House of Canada Limited, Toronto.  pp. 145.
 
Werback and Murray 1994. Botanical Influences on Illness. Third Line Press. Tarzana, CA.
 
Yam, Eliraz and Berry 1996: Diet and disease–the Israeli paradox: possible dangers of a high omega-6 polyunsaturated fatty acid diet. Israel Journal of Medical Sciences 32(11):1134-43.
    
     
Aditional Information:    

Alpha-Linolenic Acid versus Fish Oils:
Fish contain the same long-chain omega-3 fatty acids found in humans, however, many people do not like eating fish and there are also concerns about pollution affecting fish stocks. As such, many people prefer to use plant sources of omega-3 fatty acids (alpha-linolenic acid) to maintain adequate levels of longer chain omega-3s within the body. It is very important to maintain adequate dietary intake of omega-3s from one source or the other because DHA, which is derived from ALA, is particularly concentrated in the human brain and retina, and is also found in all cell membranes.

Essential Fatty Acids for Humans: A Discussion on Breast Milk, Infant Formulas, Flax Oil, Fish Oils and other Dietary Oils
By Suzanne Diamond, M.Sc. (Botany)
 
Essential fatty acids (EFA's), of which there are two types (omega-6s and omega-3s), are recognized as essential nutrients in most countries around the world. Unfortunately, many people still do not know of their fundamental importance to health. In Canada, scientists and nutritionists have tried to address this problem and have detailed their recommendations in the 1990 Health and Welfare Canada publication, Nutrition Recommendations, The Report of the Scientific Review Committee (Health and Welfare Canada, 1990). These scientists have noted that one of the two EFAs is particularly neglected by the modern diet, specifically those of the omega-3 type (alpha linolenic acid (ALA)). In fact, infant formulas sold around the world generally lack the important omega-3 EFA's. Because of the critical importance of EFAs for health and other nutritional factors found in human breast milk, the WHO and other large health organizations strongly recommend that women breast feed for as long as possible up to two years or so. These organizations have also initiated laws to prevent the promotion of infant formulas around the world. Some countries that are more up to date on current EFA research, such as Australia and Britain, have also taken steps to ensure that infant formulas contain all the essential fatty acids found in human breast milk.
 
(See Health and Welfare Canada quotes listed at the bottom of this article  – originally published as a side bar).
 
Diets low in omega 3's pose a risk for developing heart disease, stroke, cancer and ecclampsia in pregnant women (Bibus et al. 1998). Pregnant women that consume a diet low in omega 3 fatty acids are 3 times more likely to develop pregnancy related
hypertension or pre-ecclampsia. This syndrome is the number one cause of maternal mortality in industrialized nations and is thought to occur because of an imbalance between eicosanoids (hormones) that control vascular tone.
 
Omega-3 deficiency has also been correlated by multiple studies with behavioural and emotional problems including the incidence and severity of depression (including postpartum), violent behaviour, addictive habits and aggression.
 
What happens when infants and children do not get enough essential fatty acids? They can suffer from neurological and eyesight disorders, eczema, attention deficit disorder hyperactivity and other serious conditions. Adults with an EFA deficiency are prone to hormone imbalances, cancer, atherosclerosis and cardiovascular disease.
 
People in developed countries, in general, get too much sticky-type fats in their diet and not enough essential fats. This problem is at the heart of the current health crisis and could be quickly remedied if people were simply better informed about the power of including 3 to 4 teaspoons of oil rich in omega-3 EFA's in their daily diet. Good dietary sources of omega-3s include fatty fish (mackerel, anchovies, herring, salmon, tuna – but not cod or cod liver oil (Carper 1993)) and/or premium quality (certified organic and cold pressed) flax seed oil.
 
Essential Fatty Acids for Total Wellness
There is much talk these days in the media about a low-fat diet or a no-fat diet, but in fact certain fats are absolutely essential for health. Few people appreciate just how important 'good' fats are for health, and conversely just how detrimental 'bad' fats or not enough good fat in the diet can be. To quote Dr. Jacqueline Stordy, BscN, PhD, “Fat is usually regarded as a nutrient that should be avoided at all costs, but that is not the case.”
 
There are two fatty acids that are essential for life – linoleic acid (LA) in the omega-6 family and alpha-linolenic acid (ALA) in the omega-3 family. Like vitamins, these essential fatty acids can't be produced by the body and therefore must be obtained through the diet. LA is found in certain seed oils, while ALA is mainly found in dark green leafy vegetables and flaxseed oil”. LA and ALA must be obtained from foods in the proper balance because they are required as precursors for many biologically essential molecules (Horrobin 1992).
 
Together, LA and ALA in an approximately equal ratio should comprise at least 5% of daily calories (especially for children), but the average North American diet often does not provide this absolute requirement for health (Siguel 1998; Holman 1996; Lassere et al. 1985). It is estimated that most people are deficient in essential fatty acids – especially the omega-3 type.
 
In order to be useful to the body, LA and ALA must be converted by a series of steps in the body to longer chain fatty acids; arachidonic acid (AA); gamma linolenic acid (GLA which converts to AA); and docosahexaenoic acid (DHA). These conversion can be slowed down by many lifestyle factors, including a diet rich in saturated fats and trans-fatty acids, stress, viral infections, too much alcohol or cholesterol and various illnesses.
 
Human breast milk is rich in essential fatty acids (depending on the mother's diet), while infant formula is often lacking in important EFA's. Research has proven that children who are not breast fed long enough, or at all, are at much greater risk of developing several diseases including: eczema, asthma, allergies, eyesight disorders, dyslexia, dyspraxia and attention deficit disorder hyperactivity. According to Dr. Stordy's research, these diseases often occur together or are called “clustered” by medical researchers and are related to what is called, “leaky gut syndrome” (often stemming from an omega-3 deficiency).
 
When travelling through Ireland in 1998 on a lecture tour, I met several women who complained of their children suffering from eczema ever since they were babies. When asked when they stopped breast-feeding, it invariably coincided with when the child developed the problem. One mother explained that her child had terrible eczema ever since he was five days old; when asked when she had stopped breast-feeding, she explained that she had never breast-fed. Thankfully, clinical studies are proving that these conditions can be reversed with EFA supplementation and there has been remarkable success with EFA's for helping kids to get off of Ritalin and even reverse dyslexia and dyspraxia (Stevens et al. 1996; Stevens et al. 1995; Stordy 1995).
 
Why are EFAs so Important for Health?
Every cell of the body has a phospholipid membrane and that lipid is made up of essential fatty acids: 60% EFA's for most cells and 80% EFA's for brain and nerve cells. The human brain overall is largely made out of lipids and half of these are supposed to be DHA; another large percentage is AA. The human retina is fully 60% omega-3! These fats are proven to be extremely important for brain and retinal development in infants (Brown et al. 1998). Studies have also shown that increased levels of omega-3s in the diet increases the flexibility of red blood cells for passing through capillaries and blood vessels within only three days and reduces and/or normalizes blood platelet stickiness. This translates into a 27% reduced risk of heart attack for those who have already had a heart attack and are at risk of having another while a low fat diet or a high fibre diet had no effect on reducing risk of heart attack (Carper 1993).
 
The human body has enzymes that convert the short chain fatty acids, ALA and LA, into the long chain fatty acids found in cells and tissues. Certain diseases are associated with an inability of the body to produce the enzymes needed to convert the short-chain EFA's to their longer-chain derivatives, such as learning disorders, depression, diabetes, Crohn's disease and Multiple sclerosis (Carper 1997; Holman 1996; Horrobin 1992). But often, the real underlying cause for a deficiency in these compounds is over-saturation of the diet with hydrogenated and denatured fats (from cooking and over-processing) and other bad fats (Erasmus 1993).
 
ALA is concentrated in flaxseed oil (57%), certain micro-algae that fish feed on (42%) (Davidson et al. 1997; Conquer and Holub 1996; Innis and Hansen 1996) and fatty fish like tuna and salmon (30%). Lower levels are found in pumpkin (10%) and canola oils (10%) and in dark green leafy vegetables, grasses and common herbs such as plantain and purslane (Erasmus 1993; Duke 1992). Omega-3 EFA's are important for membrane fluidity of all cells of the body; they also protect the body against abnormal blood clotting and are anti-inflammatory (Siguel 1996; Davidson and Liebson  1986). Many popular vegetable oils (i.e. corn, safflower, sunflower) are high in omega-6 EFA's but are completely lacking in omega-3s. Certain oils, such as evening primrose, borage and black currant, contain GLA, which is a precursor for dihomogamma-linolenic acid, an EFA found concentrated in human breast milk and associated with beneficial anti-inflammatory prostaglandins. Clinical trials have demonstrated benefits with GLA and other EFA's for treating diabetic neuropathy (Keen et al. 1993), infantile atopic eczema (Fiocchi et al. 1994), mastalgia (Gately et al. 1992), rheumatoid arthritis (Belch et al. 1988), osteoporosis (Papendorp et al. 1995; Griffiths 1990) and postviral fatigue syndrome (Behan et al. 1990). The myriad health benefits of EFA's are well established, including their role in prostaglandin production and hormone balance (Briggs 1986; Duke 1988; Karmali 1989).
 
The following paragraphs delineate the source of the pervasive omega-3 EFA deficiency seen in the industrialized world today (largely taken from Bibus et al. 1998).
 
Origin of Pervasive Omega-3 EFA Deficiency
The omega 3 status of Americans is one of the lowest in the world. “Once abundant in the diet, omega 3 and 6 highly unsaturated fatty acids (HUFA) currently comprise a very small amount of the fat in the American diet, on the order of 200 milligrams per day per person or 0.25% of total fat intake”. Healthy diets for adults contain 5 to 7 grams of omega 3's alone per day!
 
Essential fatty acid profiles of food animals in the modern world, including chickens (eggs), pigs, cattle (meat and milk), have changed as a result of feeding practices. Bibus and others (1998) conclude that “feed lot practices using corn almost exclusively have created a national meat supply that is very low in omega 3 and high in omega 6.” Animals once raised in a free ranging environment with a diet balanced in grasses and grains are now raised with feed lot practices raised almost exclusively on corn. Even fish are being farmed on corn ration diets. In contrast, Nigerians and Australians, who still consume range fed animals, and countries like Sweden, Kerala Indians, Eskimos and Greenlandic Yupiks who regularly consume fish, have good omega 3 profiles and are known for their low to nonexistent rates of heart disease.
 
Range fed chicken egg yolks have an omega 6 to omega 3 ratio of 1:1 while commercially fed chicken eggs are nearly double that, 2:1. Research as far back as 1968 recognized that range fed animals contained higher amounts of omega 3 fatty acids. In comparing African cattle (range fed) to European domesticated animals, Crawford reported a polyunsaturated  to saturated ratio of 0.7 for African ruminants compared to 0.1 for domesticated beef. Striated muscle from the African cattle contained significant amounts of EFA's with 16% HUFA in tissue acids with a ratio of omega 6 to omega 3 of 3:1. Commercial beef in this country contains almost non-detectable amounts of these fatty acids. The wild pig has 35% polyunsaturated fatty acids in their adipose tissue, 17.5% as linoleic and 17.5% as linolenic or a ratio of 1:1 compared to corn fed animals whose ratio is around 20:1.
 
Even some of the vegetable oils that we use have been purposely bred and genetically engineered to reduce the omega 3 content, such as soy, in order to extend shelf-life and increase the oil's stability. Original soy varieties have an omega 3 content of approximately 8% compared to only 3% now.
 
In some populations in North America, the current ratio of omega 6 to omega 3 may have decreased in the past few years from 30:1 to 12:1 (although some studies have not found the ratio improved), due to the increase in canola oil consumption which has approximately 10% of omega 3 (this is significantly more than corn and other commonly used vegetable oils). But according to Bibus and other researchers (1998), “This modest increase in omega 3 status is still considered too low to support significant deposition of omega 3 fatty acids in the plasma or tissue”.
 
If we are to model our diets to that of other cultures who have better health and better omega 3 status, we must either consume more flax and fish oil and/or reduce the omega 6 to omega 3 ratio to near 1:1. The 1:1 ratio is estimated to have been the ratio of Paleolithic man, reputed to be our direct predecessor. Not only did our ancestors eat a more natural diet, they also ate animals that ate a similar diet, balanced in EFAs, and thus their tissues were enriched in omega 3s as well. It is estimated that our species has existed on a balanced EFA diet for the past 400,000 years. It has only been within the last 100 years that our dietary fatty acid composition has changed for the worse…

Too Much Omega-6 without Adequate Omega-3 Leads to Disease
Unfortunately, the story gets more complex… Many studies are showing that n-6 fatty acids, although they are essential, when they are excessive in the diet – especially in the absence of adequate levels of omega-3's, they are associated with blood platelet stickiness, high cholesterol, atherosclerosis and heart disease (Haban et al. 1998). Unfortunately, many people in our culture are deficient in omega-3 fatty acids and have excesses of omega-6's (20x higher in the diet than omega-3's) and this is thought to be the root cause of many diseases and much suffering in our society (Allman et al. 1995). Several studies have demonstrated that omega-6 found in corn and safflower oils can act as precursors for intermediates involved in the growth of mammary tumors when fed to animals, whereas polyunsaturated omega-3's found in fish and flax can inhibit these effects (Bagga et. al. 1997). Medical researchers now consider that too much omega-6 EFA's cause a diet-related tendency for severe thrombotic, arthritic and other disorders related to (n-6) eicosanoids (prostaglandins, leukotrienes, lipoxins, etc.) (Lands et al. 1992).  In fact, research has demonstrated that an excess of n-6 EFA's promotes high blood levels of estradiol, a marker for high susceptibility to breast cancer (Kushi 1992; Holm 1993; Howe 1990). Perhaps this explains why Eskimos can have diets very rich in fish oil and marine-animal type fats (essentially all omega-3) without developing the 'diseases of affluence' that are associated with beef, pork, poultry, dairy and processed vegetable oils. Two cultures with notably lower rates of cardiovascular disease have quite high intakes of n-3's including the Siberian Yupiks and Greenlandic Eskimos who consume a mean 7.0g/day, twice the 3g/day associated with favorable effects (Nobmann et al. 1998).
 
Aside from an excess of these sticky-type fats in the average American diet, over-processing of the oils can destroy their usefulness for the human body. Damaged oils (from heating and hydrogenation) cause fatty acids  to change configuration from cis to trans, thus making them useless for the body. These fats often become sticky and can cause lipid peroxidization within the body. The resulting free radical cascades can cause accelerated aging of tissues and, in the arteries, can cause atherosclerosis (Harris 1993). Oil absorbs oxygen much more readily than water does. In fact, if you leave a glass of oil out on the counter, it will go rancid quite quickly. Just like butter will go rancid if left out too long and just like metal will rust if exposed to the elements, so too fats that accumulate in arteries are prone to oxidation. This causes much of the tremendous rates of heart and cardiovascular disease in our society.
 
Medical studies are finding that the most effective prevention of heart attacks is not a low fat diet or a high fibre diet, but the inclusion of omega-3 essential fatty acids in the diet. This alone reduces the risk of heart attack by about 27%, according to one study (Billman 1994; Burr 1989; Rousseau et al. 1998; Carper 1993). The benefits of n-3's do not take long to take effect either: within three days increased levels of n-3's in the diet have been shown to increase the flexibility of red blood cells for passing through capillaries (Carper 1993). Education regarding essential fatty acids does seem to influence dietary practices and ultimately improve EFA intakes (Umemura et al. 1997).
 
Interestingly, Israel has one of the highest omega-6 to saturated fatty acid ratios in the world. The diets of Israeli Jews are generally 8% richer in n-6 EFA's than in the U.S. and 10-12% higher than in most European countries. The differences in diet are so dramatic that researchers consider this as a dietary experiment of the effect of a high n-6 diet, which was, until recently, highly recommended. Now that researchers understand the inherent problems of excess n-6 EFA's in the diet, especially in the absence of adequate n-3's, it is easy to explain the 'paradoxically' high prevalence of cardiovascular diseases, hypertension, non-insulin-dependent diabetes mellitus and obesity. All of these diseases are associated with hyperinsulinemia (HI) and insulin resistance (IR) and are grouped together as the insulin resistance syndrome or syndrome X. There is also an increased cancer incidence and mortality rate, especially in women, compared with western countries. The researchers conclude that, “high omega-6 linoleic acid consumption might aggravate HI and IR; such diets, rather than being beneficial, may have some long-term side effects within the cluster of hyperinsulinemia, atherosclerosis and tumorigenesis” (Yam, Eliraz and Berry 1996). As mentioned previously, excesses of n-6 EFA's promote high blood levels of estradiol (Kushi 1992; Lee 1991; Lee 1991b; Michnovicz 1990). PMS is also associated with elevated estrogen (estradiol) levels. High circulating estrogen levels in the blood tend to increase insulin levels and this reduces blood sugar (Lee 1991; Lee 1991b; Peat 1982; Reinish 1978). Low blood sugar leads to irritability and this is one of the main problems with PMS. Thus, estrogen dominance, often a function of excess n-6 in the diet, has been clearly linked to hyperinsulinemia.

The newest research seems to indicate that the best oils to use for cooking with heat are saturated oils such as from coconut and palm or monounsaturated oils such as olive oil (which contains a small amount of n-3 EFA's and has been used for thousands of years with noted health benefits (Weil 1995). Avacadoe and macadamia nut oils are also mostly monounsaturated (contain only one double bond) and may therefore be less reactive at high temperatures than the polyunsaturated oils (corn, safflower, sesame, soy, sunflower, flax). Other largely monounsaturated oils include almond, walnut and peanut (Carper 1993). Several studies have shown that monounsaturated oils are heart-smart: they reduce the bad LDL cholesterol in arteries and increase the good HDL cholesterol (Carper 1993). Excessive saturated fats from animal products (beef, pork, lamb, unskinned chicken, duck and all dairy products) and refined vegetable oils (especially after heating) are linked to high cholesterol and many other diseases of the vascular system and are therefore seen as hazardous to health. Hydrogenated oils, like those used for making margarine and shortenings, are chemically modified and are usually highly refined compounds that are not natural. They are also saturated and therefore hazardous to cardiovascular health. Processing of oils also tends to destroy their usefulness for the human body and may make them detrimental to health. For this reason, it is recommended that people only use cold-pressed, extra virgin oils. For optimal health, make sure to buy all of your culinary oils as cold pressed, certified organic and sold in dark amber glass bottles to keep out all light and oxygen. This is recommended in order to avoid consuming damaged fats and trans fats, which can cause atherosclerosis and free radical damage within your body while also not providing the essential fats that you need. And a final word from Udo Erasmus, author of the best selling book, “Fats that Heal, Fats that Kill”, “The only oil to fry with is water”!

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To quote from the 1990 Health and Welfare Canada report, “The n-6 and n-3 families of polyunsaturated fatty acids (also known as omega-6 and omega-3 fatty acids) are not interconvertible. These fatty acids can be synthesized de novo by plants but not by animals, which are unable to insert double bonds at the n-6 and n-3 positions. Members of these families are important components of cell membranes and serve as precursors of a variety of biologically-active compounds, known as eicosanoids, which include prostaglandins, thromboxanes and leukotrienes. Since lack of these fatty acids leads to deficiency symptoms and they can be obtained only from the diet, they are essential dietary nutrients.”
 
“Docosahexaenoic acid (22:6 n-3), the last member of the n-3 series, is concentrated in the photoreceptor membranes of the retina and is present in substantial amounts in the brain lipids of various species. A deficiency of this n-3 fatty acid leads to loss of visual acuity and skin lesions in monkeys.” Subsequent studies have shown that eyesight disorders and skin lesions were cured in human infants by n-3 fatty acids.
 
“In humans, DHA accumulates in the brain during the rapid growth spurt which occurs between the third trimester of pregnancy and eighteen months post partum. Red blood cells from human infants fed formula low in ALA had lower levels of DHA than those from breast-fed infants. The latter received about 0.3% of total fatty acids as long chain omega-3s as well as 0.6% as ALA.”
 
“Without adequate information on infant requirements for polyunsaturated fatty acids, the best guide is the composition of human breast milk. Data from several countries indicate that the extra long-chain n-3 and n-6 fatty acids are present in milk in low concentrations and that the most prevalent n-3 fatty acid is linolenic at approximately 1% of total fatty acids. Neuringer and Conner (1986) suggested that the ratio of n-6 to n-3 should be between 4:1 to 10:1, particularly during pregnancy, lactation and infancy.”
 
Summary:
Basically, LA and ALA are the ESSENTIAL fatty acids AA, GLA and  DHA are derivatives that the body can make from these essential building blocks. The big problem is that many people get way too much bad fats (trans fats and hydrogenated oils) almost entirely of the omega-6 family which causes too much AA – leading to inflammation and hormone imbalance. GLA is also converted into AA, although it seems to bypass a problematic stage in the conversion of LA to AA and provides benefits for women suffering from hotflashes and PMS, etc. The theory is that because of dietary factors and lifestyle factors that the enzymes required to convert the short chain EFAs into their long chain derivates are not able to do so – they are tied up with the bad fats. But I think that the real problem is that most people simply don't get the right balance of omega 3 (ALA) to omega 6 (LA) in their diet – they just get WAY too much omega 6. This is the problem that Udo's Oil addresses so nicely because it has flax oil rich in ALA – but there are a lot of researchers just promoting fish oil because they don't understand entirely what is going on. Fish oils are best for people suffering from severe fatty acid deficiency (resulting in different diseases) but flax oil can often do the same thing at a much lower price and without the worry of contamination from river/ocean pollution and low fish stocks. Some people also get confused about whole flax seed and the benefits that it provides. Whole flax seeds and flax press cake (defatted flax seeds) provide some omega-3 fatty acids (although you would have to eat quite a bit to get the recommended 3-7 grams of omega-3 EFAs per day for an adult) but mostly they are beneficial as a source of flaxseed lignans, phytoestrogens with strong anticancer activity and proven cholesterol lowering effects (ie. based on human, placebo controlled clinical trials, within three weeks of taking 50g of flaxseed/day in four flax muffins brings a 9.8% reduction in LDL cholesterol and 19.8% reduction in Lp(a)). If, however, the flaxseeds are not ground up before eating them then they will not be digested and will pass right through the digestive tract. It is beneficial to use both the seed and the oil of flaxseed for maintaining  health.

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