The Great Conola
By Sally Fallon and Mary G. Enig, PhD
Canola oil is "widely recognized as the healthiest salad and cooking oil available to consumers." It was developed through hybridization of rape seed.
Rape seed oil is toxic because it contains significant amounts of a poisonous substance called erucic acid.
Canola oil contains only trace amounts of erucic acid and its unique fatty acid profile, rich in oleic acid and low in saturated fats, makes it particularly beneficial for the prevention of heart disease. It also contains significant amounts of omega-3 fatty acids, also shown to have health benefits. This is what the food industry says about canola oil.
Canola oil is a poisonous substance, an industrial oil that does not belong in the body. It contains the infamous chemical warfare agent mustard gas,hemagglutinins and toxic cyanide-containing glycocides; it causes mad cow disease, blindness, nervous disorders, clumping of blood cells and depression of the immune system. This is what detractors say about canola oil.
How is the consumer to sort out the conflicting claims about canola oil? Is canola oil a dream come true or a deadly poison? And why has canola captured so large a share of the oils used in processed foods?
Let's start with some history. The time period is the mid-1980s and the food industry has a problem. In collusion with the American Heart Association, numerous government agencies and departments of nutrition at major universities, the industry had been promoting polyunsaturated oils as a heart-healthy alternative to "artery-clogging" saturated fats.
Unfortunately, it had become increasingly clear that polyunsaturated oils, particularly corn oil and soybean oil, cause numerous health problems, including and especially cancer.1
The industry was in a bind. It could not continue using large amounts of liquid polyunsaturated oils and make health claims about them in the face of mounting evidence of their dangers. Nor could manufacturers return to using traditional healthy saturates -- butter, lard, tallow, palm oil and coconut oil -- without causing an uproar. Besides, these fats cost too much for the cut-throat profit margins in the industry.
The solution was to embrace the use of monounsaturated oils, such as olive oil. Studies had shown that olive oil has a "better" effect than polyunsaturated oils on cholesterol levels and other blood parameters. Besides, Ancel Keys and other promoters of the diet-heart idea had popularized the notion that the Mediterranean diet -- rich in olive oil and conjuring up images of a carefree existence on sun-drenched islands -- protected against heart disease and ensured a long and healthy life.
The National Heart, Lung and Blood Institute (NHLBI) sponsored the First Colloquium on Monounsaturates in Philadelphia. The meeting was chaired by Scott Grundy, a prolific writer and apologist for the notion that cholesterol and animal fats cause heart disease. Representatives from the edible oil industry, including Unilever, were in attendance.
The Second Colloquium on Monounsaturates took place in Bethesda, Maryland, early in 1987. Dr. Grundy was joined by Claude Lenfant, head of the NHLBI, and speakers included Fred Mattson, who had spent many years at Proctor and Gamble, and the Dutch scientist Martign Katan, who would later publish research on the problems with trans fatty acids. It was at this time that articles extolling the virtues of olive oil began to appear in the popular press.
Promotion of olive oil, which had a long history of use, seemed more scientifically sound to the health-conscious consumer than the promotion of corn and soy oil, which could only be extracted with modern stainless steel presses. The problem for the industry was that there was not enough olive oil in the world to meet its needs. And, like butter and other traditional fats, olive oil was too expensive to use in most processed foods. The industry needed a less expensive monounsaturated oil.
Rapeseed oil was a monounsaturated oil that had been used extensively in many parts of the world, notably in China, Japan and India. It contains almost 60 percent monounsaturated fatty acids (compared to about 70 percent in olive oil). Unfortunately, about two-thirds of the mono-unsaturated fatty acids in rapeseed oil are erucic acid, a 22-carbon monounsaturated fatty acid that had been associated with Keshan's disease, characterized by fibrotic lesions of the heart.
In the late 1970s, using a technique of genetic manipulation involving seed splitting,2 Canadian plant breeders came up with a variety of rapeseed that produced a monounsaturated oil low in 22-carbon erucic acid and high in 18-carbon oleic acid.
The new oil referred to as LEAR oil, for Low Erucic Acid Rapeseed, was slow to catch on in the US. In 1986, Cargill announced the sale of LEAR oil seed to US farmers and provided LEAR oil processing at its Riverside, North Dakota plant but prices dropped and farmers took a hit.3
Before LEAR oil could be promoted as a healthy alternative to polyunsaturated oils, it needed a new name. Neither "rape" nor "lear" could be expected to invoke a healthy image for the new "Cinderella" crop. In 1978, the industry settled on "canola," for "Canadian oil," since most of the new rapeseed at that time was grown in Canada.
"Canola" also sounded like "can do" and "payola," both positive phrases in marketing lingo. However, the new name did not come into widespread use until the early 1990s.
An initial challenge for the Canola Council of Canada was the fact that rapeseed was never given GRAS (Generally Recognized as Safe) status by the US Food and Drug Administration. A change in regulation would be necessary before canola could be marketed in the US.4 Just how this was done has not been revealed, but GRAS status was granted in 1985, for which, it is rumored; the Canadian government spent $50 million to obtain.
Since canola was aimed at the growing numbers of health-conscious consumers, rather than the junk food market, it required more subtle marketing techniques than television advertising. The industry had managed to manipulate the science to make a perfect match with canola oil -- very low in saturated fat and rich in monounsaturates.
In addition, canola oil contains about 10 percent omega-3 fatty acids, the most recent discovery of establishment nutritionists. Most Americans are deficient in omega-3 fatty acids, which had been shown to be beneficial to the heart and immune system. The challenge was to market this dream-come-true fatty acid profile in a way that would appeal to educated consumers.
Canola oil began to appear in the recipes of cutting edge health books, such as those by Andrew Weil and Barry Sears. The technique was to extol the virtues of the Mediterranean diet and olive oil in the text, and then call for "olive oil or canola oil" in the recipes. One informant in the publishing industry told us that since the mid 1990s, major publishers would not accept cookbooks unless they included canola in the recipes.
In 1997, Harper Collins engaged Dr. Artemis Simopoulos to write a cookbook featuring the health benefits of omega-3 fatty acids.5 Dr. Simopoulos was a pediatrician who had served for nine years as chair of the Nutritional Coordinating Committee of the National Institutes of Health before becoming president of the Center for Genetics, Nutrition and Health.
She had published several papers on omega-3 fatty acids, calling attention to their disappearance from the food supply due to the industrialization of agriculture. Her most famous paper, published in 1992 in the American Journal of Clinical Nutrition, compared omega-3 levels in supermarket eggs from hens raised on corn with eggs from hens allowed to roam and eat a more varied diet.6 The more natural eggs contained twenty times more omega-3 than supermarket eggs.
Simopoulos's The Omega Plan came out in 1998 and was reissued as The Omega Diet in 1999. The book discusses the virtues of monounsaturated and omega-3 fatty acids in the Mediterranean diet.7 Since unprocessed canola oil contains not only lots of monounsaturated fatty acids, but also a significant amount of omega-3, it shows up in most of the book's recipes. Simopoulos claims that the Mediterranean diet is low in saturated fat and recommends lean meat and low fat yogurt and milk as part of her regime.
The canola industry's approach -- scientific conferences, promotion to upscale consumers through books like The Omega Diet and articles in the health section of newspapers and magazines -- was successful. By the late 1990s, canola use had soared, and not just in the US.
Today China, Japan, Europe, Mexico, Bangladesh and Pakistan all buy significant amounts. Canola does well in arid environments such as Australia and the Canadian plains, where it has become a major cash crop. It is the oil of choice in gourmet and health food markets like Fresh Fields (Whole Foods) markets, and shows up in many supermarket items as well.
It is a commonly used oil in sterol-containing margarines and spreads recommended for cholesterol lowering. Use of hydrogenated canola oil for frying is increasing, especially in restaurants.
Reports on the dangers of rapeseed oil are rampant on the internet, mostly stemming from an article, "Blindness, Mad Cow Disease and Canola Oil," by John Thomas, which appeared in Perceptions magazine, March/April 1996. Some of the claims are ludicrous. Although rape is a member of the brassica or mustard family, it is not the source of mustard gas used in chemical warfare.
Glycosides or glycosinolates (compounds that produce sugars on hydrolysis) are found in most members of the brassica family, including broccoli, kale, cabbage and mustard greens. They contain sulfur (not arsenic), which is what gives mustard and cruciferous vegetables their pungent flavor.
These compounds are goitrogenic and must be neutralized by cooking or fermentation. As rapeseed meal was high in glycosides, it could not be used in large amounts for animal feeding. However, plant breeders have been able to breed out the glycosides as well as the erucic acid from canola oil.8 The result is a low-glycoside meal that can be used as an animal feed. In fact, canola meal for animal feed is an important Canadian export.
Hemagglutinins, substances that promote blood clotting and depress growth, are found in the protein portion of the seed, although traces may show up in the oil. And canola oil was not the cause of the mad cow epidemic in Britain9, although feeding of canola oil may make cattle more susceptible to certain diseases.
Like all fats and oils, rapeseed oil has industrial uses. It can be used as an insecticide, a lubricant, a fuel and in soap, synthetic rubber and ink. Like flax oil and walnut oil, it can be used to make varnish. Traditional fats like coconut oil, olive oil and tallow also have industrial uses, but that does not make them dangerous for human consumption.
We have had reports of allergies to canola, and internet articles describe a variety of symptoms -- tremors, shaking, palsy, lack of coordination, slurred speech, memory problems, blurred vision, problems with urination, numbness and tingling in the extremities, and heart arrhythmias -- that cleared up on discontinuance of canola. None of this has been reported in the medical journals, however.
Writing for the Washington Post, Professor Robert L Wolke (
The Great Con-ola was published in Nexus Magazine, Aug/September 2002 as well as in Wise Traditions, the quarterly publication for the Weston A. Price Foundation
Sally Fallon is President of the Weston A. Price Foundation and author ofNourishing Traditions: The Cookbook that Challenges Politically Correct Nutrition and the Diet Dictocrats, NewTrends Publishing, 2000 (877-707-1776, newtrendspublishing.com)
Mary G. Enig, PhD, FACN, is Vice President of the Weston A. Price Foundation, President of the Maryland Nutritionists Association and author ofKnow Your Fats: The Complete Primer for Understanding the Nutrition of Fats, Oils and Cholesterol, Bethesda Press, 2000 (301-680-8600, bethesdapress.com)
1. MG Enig and SW Fallon. The Oiling of America. www.westonaprice.org/oiling.htm
2. RK Downey. Genetic Control of Fatty Acid Biosnythesis in Rapeseed. Journal of the American Oil Chemists Society, 1964;41:475-478.
3. Journal of the American Oil Chemists' Society, December 1986;63(12):1510.
4. Canola - a new oilseed from Canada. Journal of the American Oil Chemists'Society, September 1981:723A-9A.
5. The amount of the advance was $350,000. Personal email communication, Jo Robinson, co-author of The Omega Diet.
6. AP Simopoulos and N Salem, Jr. Egg yolk as a source of long-chain polyunsaturated fatty acids in infant feeding. American Journal of Clinical Nutrition, 1992;55
7. AP Simopoulos and J Robinson. The Omega Plan. Harper Collins Publishers, New York, NY, 1998.
8. Canola - a new oilseed fromCanada. Journal of the American Oil Chemists'Society, September 1981:723A-9A.
9. M Purdey. Educating Rita. Wise Traditions, Spring 2002;3(1):11-18.
10. When we contacted Dr. Wolke to provide him with evidence of
canola dangers, he was dismissive.
11. RO Vles and others. Nutritional Evaluation of Low-Erucic-Acid Rapeseed Oils. Toxicological Aspects of Food Safety, Archives of Toxicology, Supplement 1, 1978:23-32
12. HL Trenholm and others. An Evaluation of the Relationship of Deitary Fatty Acids to Incidence of Myocardial Lesions in Male Rats. Canadian Institute of Food Science Technology Journal, October 1979;12(4):189-193
13. JKG Kramer and others. Reduction of Myocardial Necrosis in Male Albino Rats by Manipulation of Dietary Fatty Acid Levels. Lipids, 1982;17(5):372-382.
14. FD Sauer and others. Additional vitamin E required in milk replacer diets that contain canola oil. Nutrition Research, 1997;17(2):259-269.
15. JK Kramer and others. Hematological and lipid changes in newborn piglets fed milk-replacer diets containing erucic acid. Lipids, January 1998;33(1):1-10.
16. SM Iunis and RA Dyer. Dietary canola oil alters hematological indices and blood lipids in neonatal piglets fed formula. Journal of Nutrition, July 1999;129(7):1261-8.
17. WMN Ratnayake and others. Influence of Sources of Dietary Oils on the Life Span of Stroke-Prone Spontaneously Hypertensive Rats. Lipids, 2000;35(4):409-420.
18. MN Wallsundera and others. Vegetable Oils High in Phytosterols Make Erythrocytes Less Deformable and Shorten the Life Span of Stroke-Prone Spontaneously Hypertensive Rats. Journal of the American Society for Nutritional Sciences, May, 2000;130(5):1166-78
19. Federal Register, 1985.
20. OA Levander and MA Beck. Selenium and viral virulence. British Medical Bulletin, 1999;55(3):528-33.
21. H Gerster. Can adults adequately convert alpha-linolenic acid (18:3n-3) to eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3)? International Journal of Vitamin and Nutrition Research 1998;68(3):159-73.
22. Wall Street Journal, June 7, 1995, p. B6.
23. MG Enig. Benefits of Saturated Fats. Wise Traditions, Summer 2000;1(2):49.
24. S O'Keefe and others. Levels of Trans Geometrical Isomers of Essential Fatty Acids in Some Unhydrogenated US Vegetable Oils. Journal of Food Lipids 1994;1:165-176.
25. JL Sebedio and WW Christie, eds. Trans Fatty Acids in Human Nutrition, The Oily Press, Dundee, Scotland, 1998, pp 49-50.
26. MG Enig, Trans Fatty Acids in the Food Supply: A Comprehensive Report Covering 60 Years of Research, 2nd Edition, Enig Associates, Inc., Silver Spring, MD, 1995.
27. Horrobin, David F, Prostaglandins: Physiology, Pharmacology and Clinical Significance The Book Press, Brattleboro, Vermont, 1978, p 20, 35
28. V Pala and others. Erythrocyte membrane fatty acids and subsequent breast cancer: a prospective Italian study. Journal of the National Cancer Institute, July 18, 2001;93(14):1088-95.
29. LL Rudel and others. Dietary monounsaturated fatty acids promote aortic atherosclerosis in LDL-receptor-null, human ApoB100-overexpressing transgenic mice. Arteriosclerosis, Thrombosis and Vascular Biology, November 1998;18(11):1818-27.