Experts Weigh in on Current Guidelines



Researchers, scientists, public health and medical professionals have been voicing their concerns regarding our current nutritional paradigm.  All quotes below, except where noted, are excerpted from published documents and/or public record.  


ON CURRENT DIETARY GUIDELINES IN GENERAL:

The guidelines must take a new approach, said Linda Van Horn, a professor of preventive medicine at Northwestern University and chairman of the 2010 dietary guidelines advisory committee: "What has been done till now isn't working. To do nothing more effective than we have means that five years from now we'll be in an even worse situation. And that would be unconscionable."
Linda Van Horn, PhD, RD, Chairman of the 2010 Dietary Guidelines Advisory Committee, in “Public health advocates worry that dietary advice will get lost in translation,” by Jane Black. Washington Post, October 2, 2010.

 “[T]he standards that had been applied to determining and promulgating dietary guidelines for all Americans have been insufficient to protect against the possibility of harm and in fact our analysis suggest that there indeed may be harm that can be an outcome of these guidelines.”
Paul Marantz, PhD, Professor of Clinical Epidemiology and Population Health at the Albert Einstein College of Medicine, in interview with Steve Mirksy.  Science Talk, weekly podcast of Scientific American, February, 2008.

 "The country's big low-fat message backfired," says Dr. Frank Hu, professor of nutrition and epidemiology at the Harvard School of Public Health. "The overemphasis on reducing fat caused the consumption of carbohydrates and sugar in our diets to soar. That shift may be linked to the biggest health problems in America today."
Frank Hu, MD, PhD, MPH, Professor of Nutrition and Epidemiology at Harvard School of Public Health, in “A Reversal on Carbs” by Marni Jameson.  Los Angeles Times, December 20, 2010.

 “The low-fat– high-carbohydrate diet, promulgated vigorously by the National Cholesterol Education Program, National Institutes of Health, and American Heart Association since the Lipid Research Clinics-Primary Prevention Program in 1984, and earlier by the U.S. Department of Agriculture food pyramid, may well have played an unintended role in the current epidemics of obesity, lipid abnormalities, type II diabetes, and metabolic syndromes. This diet can no longer be defended by appeal to the authority of prestigious medical organizations or by rejecting clinical experience and a growing medical literature suggesting that the much-maligned low-carbohydrate– high-protein diet may have a salutary effect on the epidemics in question.”
Sylvan Lee Weinberg, MD, MACC, Director of Medical Education at the Dayton Heart Hospital and Clinical Professor Medicine at the Wright State University School of Medicine and past President of the American College of Cardiology, “The Diet–Heart Hypothesis: A Critique.”  Journal of the American College of Cardiology, Vol. 43, No. 5, 2004.

 “The nutrient-based approach [of the current dietary guidelines] may foster dietary practices that defy common sense. Countless highly processed products are now marketed in which refined carbohydrate replaces fat, providing an aura of healthiness but without actual health benefits.  . . . Taking the nutrient approach to self-serving extremes, the food industry “fortifies” highly processed foods, like refined cereals and sugar-sweetened beverages, with selected micronutrients and re-characterizes them as nutritious. These marketing ploys provide little public health benefit and could potentially produce harm.”
Dariush Mozaffarian, MD, DrPH, Assistant Professor of Medicine at  Harvard Medical School and Associate Physician, Brigham and Women's Hospital and David S. Ludwig, MD, PhD, Associate Professor in Pediatrics at Harvard Medical School and Founding Director of the Optimal Weight for Life (OWL) clinic at Children’s Hospital, Boston.  “Dietary Guidelines in the 21st Century: a Time for Food. “ Journal of the American Medical Association.  2010; 304(6):681-682.

 “Healthy Aging DPG [Dietetics Practice Group]  surveyed its members regarding the proposed DGA 2010 recommendations.  Our response below synthesizes these comments. . . .
     Saturated fat – The effects of saturated fat on blood lipids needs more supporting evidence.
     Refined Carbohydrate – More emphasis on reduction of refined carbohydrates is needed.
     Protein – Plant based protein sources do not provide the high quality protein that animal sources offer. Older adults, particularly those with poor appetites, may benefit from the high quality protein and essential nutrients that animal sources provide.”
Dian Weddle, PhD, RD, FADA, Healthy Aging Chair, Healthy Aging Dietetics Practice Group, American Dietetic Association.  “Healthy Aging Provides Comments to the ADA on the Dietary Guidelines for Americans 2010.” The Spectrum, Summer 2010.

“Unfortunately, MyPyramid strays from much of the evidence generated through years of research and, in our opinion, fails to provide the public with clear information about healthy food choices.”
Stephanie E Chiuve and Walter C Willett MD MPH, Departments of Nutrition and Epidemiology, Harvard School of Public Health. “The 2005 Food Guide Pyramid: an opportunity lost?” Nature Clinical Practice. 2007;4(11):610-620.


ON CARBOHYDRATE RECOMMENDATIONS:

Speaking at the recent Friedman Symposium at Tufts University in Boston, King said her review of the evidence had identified a number of areas that were ripe for updating. . . . “One of the most significant pieces of information to come out the last four years is the relationship between different amounts of macronutrients in the diet,” King said. She noted that that current MyPyramid recommendations call for an average of 60% of energy intake from carbohydrate, 15% from protein, and 25% from fat. However, evidence has begun to accumulate suggesting that a lower intake of carbohydrate may be better for cardiovascular health. The most compelling data, in King’s view, come from the Omni-Heart study. . .  [In the Omni-Heart study] the diets lower in carbohydrate yielded improved outcomes on markers of cardiovascular health.
Janet King, PhD.  Professor of Nutrition at the University of California, Davis, Senior Scientist at the Children’s Hospital Oakland Research Institute, and Chairman of the 2005 Dietary Guidelines Advisory Committee in Clinical, in “Dietary Guidelines 2010:  What Should We Wish For?” by Kevin Lomangino, Editor.  Nutrition Insight, Volume 35, No. 1, January 2009.

"Fat is not the problem," says Dr. Walter Willett, chairman of the department of nutrition at the Harvard School of Public Health. . . .”The good news," adds Willett, "is that based on what we know, almost everyone can avoid Type 2 diabetes. Avoiding unhealthy carbohydrates is an important part of that solution."
Dr. Walter Willett, MD, DrPH, Chairman of the Department of Nutrition, Harvard School of Public Health, in “A Reversal on Carbs” by Marni Jameson.  Los Angeles Times, December 20, 2010.

 “Diets with increased protein have now been shown to improve adult health with benefits for treatment or prevention of obesity, osteoporosis, type 2 diabetes, Metabolic Syndrome, heart disease, and sarcopenia [muscle wasting that occurs in older adults]. . . . For most adults, replacing some dietary carbohydrates with protein will help to maintain body composition and mobility improve blood lipids and lipoproteins, and help to control food intake.”
Donald Layman, PhD, Department of Food Science & Human Nutrition, University of Illinois,  “Dietary Guidelines should reflect new understandings about adult protein needs.”  Nutrition & Metabolism 2009, 6:12


ON RECOMMENDATIONS TO REDUCE FAT, SATURATED FAT, AND CHOLESTEROL:

“Diets with lower percent energy from total fat do NOT reduce risk of heart disease, diabetes, cancer, or adiposity. The focus on reduction of fat in dietary guidelines has been a massive distraction and can be harmful for some if healthful fats are reduced. Advice about percent energy from fat should be removed from all dietary guidelines, and total fat should be removed from fat labels.”
Walter C. Willet, MD, DrPH, Department of Nutrition, Harvard School of Public Health, American Dietetic Association: Great Fat Debate, November 8, 2010.

“There is no significant evidence for concluding that dietary saturated fat is associated with an increased risk for heart disease. It’s time to turn the page on how we perceive saturated fats in relation to risk for heart disease. It’s the wrong message that saturated fats are artery clogging or evil.“
Ronald Krauss, MD, Director of Atherosclerosis Research, Children’s Hospital Oakland Research Institute, Boston Globe, Feb. 24, 2010.

“National guidelines/recommendations for LOW-FAT diet may be particularly inappropriate for weight loss for women with insulin resistance.”
Christopher Gardner, PhD, Director of Nutrition Studies at the Stanford Prevention Research Center and an Associate Professor of Medicine at Stanford University. Presentation at North American Association for the Study of Obesity Conference, 2008.

"Dietary fat used to be public enemy No. 1," says Dr. Edward Saltzman, associate professor of nutrition and medicine at Tufts University. "Now a growing and convincing body of science is pointing the finger at carbs, especially those containing refined flour and sugar."
Edward Saltzman, MD, Associate Professor of Nutrition and Associate Professor of Medicine at Tufts University, in “A Reversal on Carbs” by Marni Jameson.  Los Angeles Times, December 20, 2010.

“Although diets inordinately high in fat and saturated fat are associated with increased cardiovascular disease risk in some individuals, assuming that saturated fat at any intake level is harmful is an over-simplification and not supported by scientific evidence.”
Bruce German, PhD, Professor and Food Chemist in the Department of Food Science and Technology at University of California at Davis, at the American Oil Chemists’ Society Symposium, "Saturated Fats and Health: Facts and Feelings," May 5, 2009.

 “[There is] excellent evidence that carbohydrate restriction changes LDL cholesterol from the bad 'small dense' form to the lower-risk larger particles" -- a shift that represents a major reduction in risk, says Phinney.  . . . Phinney also objected to what he called the "continued demonization of saturated fats by the committee."  He cites a recent journal article that makes the case there is no evidence to support the widespread belief that the consumption of saturated fat negatively affects heart health or overall mortality.
Stephen Phinney, Professor of Medicine Emeritus at University of California at Davis, in “A Low-Carb Guru Weighs in on the Dietary Guidelines,” by Melissa Healy.  Los Angeles Times, June 29, 2010.

 “Evidence already exists that simply telling the public (and industry) ‘to reduce dietary fat’ backfired, with the introduction of high-CHO products, more sugar, more obesity and disease.  To imply that stearic acid is ‘neutral’ and should not count as a fat, or as a SFA, is false and misleading and will encourage industry to load up fats with 18:0 [stearic acid] via IE processing, which will lead to a disaster not unlike trans fat.”
K.C. Hayes, DVM, PhD,  Professor of Biology and Director Foster Biomedical Research  Laboratories at Brandeis University.  Excerpted from letter addressed to Ms. Carol Davis, Co-Executive Secretary of the DGAC, July 13, 2010.

 “Current dietary guidance appears to confuse many of our fellow citizens, which may be one reason that compliance with guidelines is poor.  One guideline in need of review is the advice to reduce dietary cholesterol.  Several recent studies have found no association between dietary cholesterol intake and coronary heart disease (CHD).  The ratio of LDL-C to HDL-C, an important indicator of cardiovascular disease risk, does not appear to be affected by dietary cholesterol . . . . The current cholesterol guideline heavily influences regulatory restrictions by the Food and Drug Administration on information that can be provided on food labels.  These restrictions inhibit the ability to inform consumers about the benefits of nutrients found in foods like eggs, e.g. choline. ”
Keith Ayoob, EdD, RD, FADA, Associate Clinical Professor at Albert Einstein College of Medicine of Yeshiva University, Children’s Evaluation and Rehabilitation Center.  Excerpted from letter addressed to Ms. Carol Davis, Co-Executive Secretary of the DGAC, April 28, 2009.

Even the American Heart Association (AHA), a leader in the campaign against dietary fat, recently revised its nutritional guidelines, increasing the daily recommendations for fat.  “The science just wasn’t there,” acknowledges Robert Eckel, [past] president of the AHA and a professor of endocrinology, metabolism, and diabetes at the University of Colorado Health Sciences Center.
Robert Eckel, past president of the American Heart Association, in “Fat is Where It’s At.”  Ode, June/July 2009, Volume 7, Issue 9.

 “In the early 1990s, we ate low-fat everything and we didn’t get thinner, says Alice Lichtenstein, a professor of nutrition science and policy at Tufts University in Massachusetts.  “There’s your proof.”
Alice Lichtenstein, vice-chair of the American Heart Association Nutrition Committee, in “Fat is Where It’s At.”  Ode, June/July 2009, Volume 7, Issue 9.

 The percentage of total fat is still recommended to be less than 35% of calories, and the rationale is to be consistent with the IOM DRI's.   However, the DRI recommendation for less than 35% of energy is entirely related to weight control, which the dietary guidelines committee concluded has no relation to the percent of calories from fat.”
Walter Willet MD MPH, Chairman of the Department of Nutrition, Harvard School of Public Health. Excerpted from letter addressed to Ms. Carol Davis, Co-Executive Secretary of the Dietary Guidelines Advisory Committee.

“There really is this growing body of research showing that dietary cholesterol is not harmful.  Certainly not harmful in most people, and maybe not harmful in anybody when you account for other factors.......Is it safe for people with heart disease to make eggs a routine part of their diet and is it better for them than what they’re currently eating?  We think it is.”
Transcript excerpted from audio/video file on April 16, 2011 (available at www.eggnutritioncenter.org) of David Katz, MD, MPH, board certified specialist in both Internal Medicine, and Preventive Medicine/Public Health, and Associate Professor (adjunct) in Public Health Practice at the Yale University School of Medicine. Katz is the Director and founder (1998) of Yale University's Prevention Research Center.

“It is imperative to clarify that extensive research does not support a consistent relationship between egg intake and CHD incidence (1,2). A review of multiple case-controlled studies measuring intake of cholesterol and disease incidence, reported that a relationship could not be clearly  established between this dietary component and increase in CHD risk. Furthermore, data gathered from Lipid Research Clinics Prevalence Follow-up Study (3), which examined both men and women (n=4546) found no significant relationships between deaths attributable to CHD and dietary cholesterol intake.
Maria Luz-Fernandez, PhD, Professor, Department of Nutritional Sciences, University of Connecticut. Excerpted from letter addressed to Ms. Carol Davis, Co-Executive Secretary of the DGAC, 4/6/2009.  (1) Hu FB et al. A prospective study of egg consumption and risk of cardiovascular disease in men and women. Journal of the American Medical Association. 1999;281:1387-1394.  (2) Howell WH et al. Plasma lipid and lipoprotein responses to dietary fat and cholesterol. American Journal of Clinical Nutrition. 1997;65:1747-1764.  (3) Esrey KL et al. Relationship between dietary intake and coronary heart disease mortality: lipid research clinics prevalence follow-up study. Journal of Clinical Epidemiology. 1996;49:211-216. 

“In my home state of Arizona, a restaurant named "Heart Attack Grill" does brisk business in Chandler, a Phoenix suburb. But the Grill's essential, in-your-face concept is that the saturated fat in beef clogs arteries, and hamburger meat is consequently among the most heart-damaging foods a human being can consume. ...The problem? It's not true. The saturated fat lauded in this menu won't kill you. It may even be the safest element of the meal.” . . . “Saturated fat is made of fatty acid chains that cannot incorporate additional hydrogen atoms. It is often of animal origin, and is typically solid at room temperature. Its relative safety has been a theme in nutrition science for at least the last decade, but in my view, a significant exoneration took place in March of this year. An analysis that combined the results of 21 studies, published in The American Journal of Clinical Nutrition found that "saturated fat was not associated with an increased risk" of coronary heart disease, stroke or coronary vascular disease.” .  . . “This contradicts nutritional dogma we've heard repeated since 1970, when a physiologist named Ancel Keys published his "Seven Countries" study that showed animal fat consumption strongly predicted heart attack risk. His conclusions influenced US dietary guidelines for decades to come, but other researchers pointed out that if 21 other countries had been included in that study, the association that Keys observed would have been seen as extremely weak.”
Andrew Weil MD,  founder and director of the Arizona Center for Integrative Medicine, excerpted from The Huffington Post, July 2, 2010, available at http://www.huffingtonpost.com/andrew-weil-md/healthy-eating_b_629422.html.


ON THE INTAKE OF HIGH LEVELS OF POLYUNSATURATED FATS IN THE DIET

“Advice to specifically increase n-6 PUFA intake, based on mixed n-3/n-6 RCT data, is unlikely to provide the intended benefits, and may actually increase the risks of CHD and death.” 
LCDR Christopher E. Ramsden MD (United States Public Health Service, Clinical Investigator National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health) et al.  n-6 fatty acid-specific and mixed polyunsaturate dietary interventions have different effects on CHD risk: a meta-analysis of randomised controlled trials. British Journal of Nutrition, Volume 104, Number 11,  December 2010. 

  
ON DAIRY AND DAIRY FAT

 "We make use of and metabolize animal fats in ways not previously understood. Today's science supports the concept that fats from a ruminant (cow, goat, sheep) provide valuable nutrients that help maintain health and prevent disease.
Dale E. Bauman, PhD Nutritional Biochemistry, Cornell University, Boston Globe, January 7, 2009

Although dairy products contain saturated fat, [Adam Lock PhD] said that the types of fatty acids in milk raise low-density lipoproteins (LDLs) and high-density lipoproteins (HDLs), and they end up canceling each other out.  And, Lock said, less fat isn’t always better. The benefits of some of these fatty acids and fat-soluble vitamins are lost when the fat is skimmed from dairy, he noted.  Children, especially should be getting the nutrients of whole dairy.  “My son drinks whole milk because that’s the best nutrient package you can get in dairy because of all the different nutrients it contains,” he said. “For growing children and teenagers, dairy products are, in my mind, a significant contribution to the diet.”
Adam Lock, Assistant Professor, Department of Animal Science, Michigan State University article in Tri City Times, June 23, 2010, available at www.tricitytimesonline.com. 

“There is increasing evidence to support that the total matrix of a food is more important than just its fatty acid content when predicting the effect of a food on CHD risk, eg, the effect of SFAs from cheese on blood lipids and CHD may be counterbalanced by the content of protein, calcium, or other components in cheese. In addition, the special fatty acid profile (rumenic acid, trans vaccenic acid, and short-chain fatty acids) may modify the effect on CHD risk.”
Arne Astrup, Jorn Dyerberg, Peter Elwood, Kjeld Hermansen, Frank B. Hu,  Marianne Uhre Jakobsen, Frans J Kok, Ronald M Krauss, Jean Michel Lecerf, Philippe LeGrand, Paul Nestel, Ulf Riserus, Tom Sanders, Andrew Sinclair, Steen Stender, Tine Tholstrup, and Walter C Willett.  The role of reducing intakes of saturated fat in the prevention of cardiovascular disease: where does the evidence stand in 2010? American Journal of Clinical Nutrition. 2011;93(4):684-688. This article reports consensus reached by all of the authors at a 2-d invitation-only symposium organized by Arne Astrum and Walter Willett and held in Copenhagen, Denmark, in May 2010.

  
ON WHOLE GRAINS AND FIBER RECOMMENDATIONS:

“The U.S. FDA defines whole grains as consisting of the intact, ground, cracked, or flaked fruit of the grains whose principal components, the starchy endosperm, germ, and bran, are present in the same relative proportions as they exist in the intact grain. . . . When considering only whole grain studies that met the FDA definition, we found insufficient scientific evidence to support a claim that whole grain intake reduces the risk of CVD.”
Fabiana F. De Moura, Kara D. Lewis, and Michael C. Falk, researchers at the Life Sciences Research Office, Bethesda, MD 20814.  “Applying the FDA Definition of Whole Grains to the Evidence for Cardiovascular Disease Health Claims.” The Journal of Nutrition, 2009; 139:2220S–6.

 “Despite dietary recommendations to increase intake of whole grains, little epidemiological evidence is available to support the physiological importance of whole-grain intake.”
Joanne Slavin, PhD, RD, Professor of Food Science at Nutrition at the University of Minnesota, member of the 2010 Dietary Guidelines Advisory Committee.  “Epidemiological evidence for the impact of whole grains on health.” Critical Reviews in Food Science and Nutrition, 1994;34(5-6):427-34. 


ON RECOMMENDATIONS TO REDUCE SODIUM:

“Authoritative recommendations, sometimes sanctioned by government, routinely call for reduced dietary sodium. However, when the strength of evidence is made explicit, it is generally acknowledged to be opinion or common ‘practice.’”
Michael H. Alderman, MD. Albert Einstein College of Medicine, Department of Epidemiology and Population Health, Bronx, New York.  “Reducing dietary sodium, the case for caution." Journal of the American Medical Association, 303(5):448-49.

“Guidance for sodium intake should target specific populations for whom a lower sodium intake is possibly beneficial. Such an approach would avoid broad proscriptive guidelines for the general population for whom the safety and efficacy are not yet defined. An appropriate next step is not to lower the sodium guideline further. Rather, the scientific community should commit to the continued evolution of the science underlying sodium’s role in normal and abnormal human physiology.”
 David McCarron, Department of Nutrition, University of California, Davis, with Tilman B Drueke, and Edward M Stricker.  “Science trumps politics: urinary sodium data challenge US dietary sodium guideline.”  American Journal of Clinical Nutrition,  2010; 92:1005–6.

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