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Edward Siguel, MD PhD |
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March 6, 1995 We applaud the USDA for acknowledging the need for EFAs in the diet. However, we dispute their contentions that the Food Pyramid provides clear direction to the American people on meeting that need, that the pyramid encourages people to add oil to low fat foods, or that Americans interpret USDA guidelines to mean that EFAs are essential to the diet. Nowhere does the pyramid suggest that "liquid vegetable oils be used most often", or that 1/3 of dietary fat be provided as vegetable oil. Lumping oils, fats and sugar at the top of the pyramid with the instruction "use sparingly" gives a clear message that EFA-rich oils are to be avoided, as if they shared the undesirable properties of sweets and fats (known as "bad" and "nutritionally useless"). The USDA reinforces this incorrect belief by treating all oils equally (despite major differences in EFA composition), and by stating that "these foods provide calories and little else nutritionally." A visit to any supermarket will reveal the highly processed nature of many foods nearly devoid of EFAs. Hardest hit are w3 fatty acids, which are drastically lowered by hydrogenation. Simopoulos has found that current w3 intake is below that of the last century, probably causing an increase in brain dysfunction, dyslexia, behavioral abnormalities, and learning abnormalities. Although the USDA acknowledges the essentiality of linoleic acid, linolenic acid is absent from their comments. The current trend towards taking more MUFAs further depletes the intake of EFAs. Many consumers use olive or corn oil, both of which contain practically no w3s. Soybean oil has both EFAs, but most soybean oil in foods is hydrogenated and thereby depleted of w3s. Furthermore, many manufacturers have shifted production towards low fat foods and removed soybean oil from their products (e.g., salad dressings and sauces). Thus, one of the last remaining sources of EFAs is disappearing from the market. Most low-fat foods are composed of processed carbohydrates with practically zero EFAs; some are high in trans fatty acids (TFAs). Companies can list a product as being low in saturated fat even though it is high in TFAs. The USDA statement that shortening ("margarine") makes up 1/3 of added fat indicates the implicit acceptance of a high TFA intake, despite the growing knowledge from our own research and that of others that TFAs are a significant coronary risk factor, and raise Total/HDL cholesterol. Commercials and government advertisements create the perceived "desirable" goal of eating no fat. In 1994, we were interviewed by more than 100 reporters in the US and abroad. It was their consensus that media and advertisements encourage people to eat zero-fat diets. Fat is presumed to be bad, and therefore less of it is better. Consumers are not told that EFAs are essential. Individuals obtaining most of their calories from very low-fat foods based on processed carbohydrates without oil supplements cannot possibly obtain enough EFAs if they follow the USDA pyramid. Because of huge variability in PUFA intake, millions of people do not eat enough PUFAs, even if "average" individual intake is adequate. Paragraph not in published letter (added material) For example, a slim woman eating 1,500 kcal/day who faithfully follows the USDA Food Pyramid easily obtains 700 calories from breads, pasta and cereals. The remaining 800 calories may come from vegetables, fruits, chicken, and low fat dairy products. From these foods she cannot possibly get 15-20 grams of w3 and w6 EFAs/day. If she is pregnant or breast feeding, her child may have impaired development. The USDA alleges that the Food Pyramid reflects up-to-date knowledge of nutrition. However, the implicit and explicit assumptions/ citations in the USDA's Pyramid justification are scientifically incorrect, as they are based on obsolete recommendations. Alternative Paragraph (added material) It does not matter if the USDA believes that Americans eat enough EFAs or if it believes that EFA deficiency is not prevalent. What matters is accurate data from blood tests, which show that deficiencies are common in the US population. We analyzed fatty acid profiles of 500+ adults from the Framingham Heart Study. More than 20% had biochemical evidence of w3 or w6 deficiency. At least 5% had deficiencies so severe that they would likely have reduced life expectancies. We found that EFA abnormalities are the most significant nutritional factor in elevated TC/HDLC. Correcting EFA deficiencies leads to a major reduction in TC/HDLC (unpublished data). Dr. Holman, who established the old criteria for EFA requirements, agrees that EFA deficiency is highly prevalent in the USA (personal communications). Paragraph not in published letter (added material) Translated into numbers for the US population, we estimate that severe EFA abnormalities affect more than 10 million people, and that significant EFA abnormalities (associated with chronic disease) affect more than 50 million people. We have been contacted by numerous physicians and patients whose TC/HDLC increased after being on a strict low-fat diet. Those whose blood we analyzed had significant EFA deficiencies. We submit that the USDA recommendations will contribute to the development of EFA abnormalities, obesity, hypertension, dyslipidemia, and overall morbidity in the 1990's. EFA abnormalities are most likely to affect children, women, blacks and Hispanics, who characteristically eat foods low in EFAs. We challenge the USDA to provide us with blood samples of individuals who eat highly processed, low-fat American diets. We will demonstrate the dangers of such diets by determining their EFA profiles. Screening selected populations for EFA abnormalities is practical and inexpensive in the context of the huge USDA budget and the billions spent on cardiovascular disease. We propose that nutritional requirements for EFAs should be based on absolute grams /kg body weight/day rather than as a percentage of daily calories. Otherwise, individuals who eat less than 1,500 kcal/day would meet the USDA recommended guidelines for EFA intake, but would become EFA deficient. In our clinical experience, the amount of PUFAs recommended by the USDA is too low for most adult Americans. By establishing an arbitrary and scientifically misleading recommendation for EFA intake, it is assured that consumers meet USDA guidelines. By refusing to fund studies on biochemical evidence of EFA deficiency, the USDA can continue to support its mistaken belief that EFA deficiency does not exist in America. The beneficiaries of this policy are bureaucrats protecting their jobs, researchers studying low-fat foods, corporations selling low-fat foods to an uninformed and mislead public, and companies selling drugs to lower abnormal cholesterol and hypertension caused by EFA deficiencies. The losers are consumers, who are faced with increasing bills, abnormal cholesterol, and chronic diseases (including heart disease), and nutritionists and patients, who face conflicting and misleading guidelines. Paragraph not in published letter (added material) Fat nutrition policy is a failure in America. People think that they can eat as much food as they want as long as it is low in fat, and they thus accumulate saturated fat (gain weight) by eating low fat foods. The 1995 Harris Poll found that 71% of Americans over 23 years of age are overweight. The percent of overweight has been increasing since 1983. It is obvious that Americans are substituting carbohydrate calories for fat. Americans are eating low fat foods as if these foods had zero calories, then wonder why they gain weight. Low fat diets have failed to control obesity in America; furthermore, morbidity from cardiovascular disease is also increasing. We propose that an EFA deficient diet would make people hungry and further contribute to obesity. Under FDA and consumer protection statutes in most states, failure to explain the need for and role of EFAs would be considered a serious misrepresentation that would subject the perpetrator to severe fines. Paragraph not in published letter (added material) Our clinical experience and research data indicate that the USDA nutrition recommendations, coupled with misleading food labels, are a major contributory factor to CAD. Unless nutrition policy is drastically changed to emphasize the need for EFAs, we are afraid that current policies may increase morbidity and mortality. The best way to control health-care costs is through self-responsibility, effective prevention, and nutrition. We urge the USDA to launch an information campaign to educate the American public about EFAs, to include EFA and TFA content in food labels, to fund further research on EFAs, and to amend nutrition policy to reflect the need for EFAs. Sincerely yours, |
See actual letter as published in the Am. J. of Clinical Nutrition, September, 1995 issue, signed by Drs. Siguel and Lerman.
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© 1998 Edward Siguel. All rights reserved |
modified 9/17/98 |