American College of Physicians: Internal Medicine — Doctors for Adults ®

Monday, September 14, 2015

Chewing the fat, again

Among my numerous colleagues, friends, and correspondents are more than a few who circulate every abstract, however obscure the source, suggesting that saturated fat has been fully exonerated, or that everything we ever thought we knew about dietary fat, health, and weight has been utterly renounced.

I confess that to some degree, I engage in counter-measures, circulating studies that show rather the contrary. Generally, my interest is balance and the weight of evidence, so I will circulate any study I consider important, whatever the conclusions. But to the extent that I represent opposition to the inclinations du jour (or du news cycle, which lasts much less than a whole jour, these jours), it is not, by any means, because I have a low-fat chip on my shoulder. Rather, as I have indicated before, I have little tolerance for the Newtonian nonsense of New-Age nutritionism: for every dietary trend, fad, or fashion, an equal, opposing, reactionary trend, fad, or fashion.

So it is that when cutting fat let us down, mostly because we approached the enterprise as a pack of gullible nincompoops, we didn't thoughtfully reconsider the proposition of mono-nutrient fixations. That might have been genuinely constructive, but at odds with the Newtonian impulse. We opted for the latter, an equal, opposite, reactionary boondoggle. Decades later, the cycle has repeated many times, and here we are, propelled this way and that by Newtonian inertia, awash in hyperendemic obesity and chronic disease, accompanied by massive food industry profits.

This, then, is the prelude to brief remarks about two recent studies that rebut many of the currently fashionable rebuttals about dietary fat.

The first was a brief, metabolic ward study by perhaps the world's leading authority on energy balance, Dr. Kevin Hall at the National Institutes of Health. The timing was somewhat ironic, given the recent, high-profile implosion of an effort overseen by other scientists, purportedly devoted to the elucidation of energy balance. That, however, is another story, already told.

Dr. Hall has developed sophisticated, and influential energy balance equations that elaborate often-neglected nuances, such as the fact that the calories required to maintain weight decline as weight declines. This, by the way, accounts for the notorious “weight loss plateau“ on which so many dieters land, even as they profess their on-going adherence to the program. Their claims are legitimate, and Dr. Hall's equations validate them.

Dr. Hall's study was both small, and of short duration, but rigorously controlled. It compared isocaloric reductions in dietary fat versus dietary carbohydrate, and showed that body fat content declined significantly more with restriction of dietary fat. This seems a quaint throwback to what we thought we knew before we learned that everything we thought we knew was a big fat lie, or a big fat surprise, but it's not. It's entirely current, meticulous research.

The second paper is one of those systematic reviews and meta-analyses we can't seem to get enough of these days, and of which we arguably get too many to propagate anything other than perennial confusion. In any event, this review, by the widely respected Cochrane Collaboration, concluded that reductions in the percentage of total calories from fat lead consistently to reductions in body fat and body weight, too. This also seems to fly in the face of what we now prefer to think about what we once thought we knew.

I note these two publications partly because they are, indeed, both noteworthy. But I note them in particular in the service of balance, and better hopes for nutritional science than a never-ending sequence of misguided action followed by errant reaction.

Science is a method for answering questions; it is, in essence, a tool. A tool is never much better than the service to which it is called. A hammer, for example, is a perfectly good tool, but a dubious choice for opening windows, although it would do the job. You might use a microscope for diagnosis the next time your toaster won't work, and you may even notice formerly undetected flaws in its façade. You are unlikely, however, to discern at high magnification the fact that it isn't plugged in.

I am not at all interested in a resurrection of a preferential focus on wholesale dietary fat restriction. We should long since have recognized that questions about this or that macronutrient and weight are rather like the use of a hammer to open a window. An outcome is generated, and mums the word about the shards of glass all over the floor.

In the real world, health, weight control, and lifelong vitality are achieved on diets that vary considerably in macronutrient composition, but that all adhere to the same basic theme: wholesome foods, in sensible combinations, plant foods predominating. A vast array of research evidence from diverse sources, including randomized controlled trials, attests to the same. Alas, it just does not seem to satisfy our Newtonian impulses, or penchant for vituperations, religiosity, and procrastination.

We know how to eat well, for weight control and health, and sustainability; we just don't want to swallow it. We would rather, it seems, just keep chewing indefinitely, on fat, or carbs, depending on your palate, and the news that broke 8 minutes ago.

David L. Katz, MD, FACP, MPH, FACPM, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care. He is a 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. He is the Director and founder (1998) of Yale University's Prevention Research Center; Director and founder of the Integrative Medicine Center at Griffin Hospital (2000) in Derby, Conn.; founder and president of the non-profit Turn the Tide Foundation; and formerly the Director of Medical Studies in Public Health at the Yale School of Medicine for eight years. This post originally appeared on his blog at The Huffington Post.

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Members of the American College of Physicians contribute posts from their own sites to ACP Internistand ACP Hospitalist. Contributors include:

Albert Fuchs, MD
Albert Fuchs, MD, FACP, graduated from the University of California, Los Angeles School of Medicine, where he also did his internal medicine training. Certified by the American Board of Internal Medicine, Dr. Fuchs spent three years as a full-time faculty member at UCLA School of Medicine before opening his private practice in Beverly Hills in 2000.

And Thus, It Begins
Amanda Xi, ACP Medical Student Member, is a first-year medical student at the OUWB School of Medicine, charter class of 2015, in Rochester, Mich., from which she which chronicles her journey through medical training from day 1 of medical school.

Ira S. Nash, MD, FACP, is the senior vice president and executive director of the North Shore-LIJ Medical Group, and a professor of Cardiology and Population Health at Hofstra North Shore-LIJ School of Medicine. He is Board Certified in Internal Medicine and Cardiovascular Diseases and was in the private practice of cardiology before joining the full-time faculty of Massachusetts General Hospital.

Zackary Berger
Zackary Berger, MD, ACP Member, is a primary care doctor and general internist in the Division of General Internal Medicine at Johns Hopkins. His research interests include doctor-patient communication, bioethics, and systematic reviews.

Controversies in Hospital Infection Prevention
Run by three ACP Fellows, this blog ponders vexing issues in infection prevention and control, inside and outside the hospital. Daniel J Diekema, MD, FACP, practices infectious diseases, clinical microbiology, and hospital epidemiology in Iowa City, Iowa, splitting time between seeing patients with infectious diseases, diagnosing infections in the microbiology laboratory, and trying to prevent infections in the hospital. Michael B. Edmond, MD, FACP, is a hospital epidemiologist in Iowa City, IA, with a focus on understanding why infections occur in the hospital and ways to prevent these infections, and sees patients in the inpatient and outpatient settings. Eli N. Perencevich, MD, ACP Member, is an infectious disease physician and epidemiologist in Iowa City, Iowa, who studies methods to halt the spread of resistant bacteria in our hospitals (including novel ways to get everyone to wash their hands).

db's Medical Rants
Robert M. Centor, MD, FACP, contributes short essays contemplating medicine and the health care system.

Suneel Dhand, MD, ACP Member
Suneel Dhand, MD, ACP Member, is a practicing physician in Massachusetts. He has published numerous articles in clinical medicine, covering a wide range of specialty areas including; pulmonology, cardiology, endocrinology, hematology, and infectious disease. He has also authored chapters in the prestigious "5-Minute Clinical Consult" medical textbook. His other clinical interests include quality improvement, hospital safety, hospital utilization, and the use of technology in health care.

Juliet K. Mavromatis, MD, FACP, provides a conversation about health topics for patients and health professionals.

Dr. Mintz' Blog
Matthew Mintz, MD, FACP, has practiced internal medicine for more than a decade and is an Associate Professor of Medicine at an academic medical center on the East Coast. His time is split between teaching medical students and residents, and caring for patients.

Everything Health
Toni Brayer, MD, FACP, blogs about the rapid changes in science, medicine, health and healing in the 21st century.

Vineet Arora, MD, FACP, is Associate Program Director for the Internal Medicine Residency and Assistant Dean of Scholarship & Discovery at the Pritzker School of Medicine for the University of Chicago. Her education and research focus is on resident duty hours, patient handoffs, medical professionalism, and quality of hospital care. She is also an academic hospitalist.

Glass Hospital
John H. Schumann, MD, FACP, provides transparency on the workings of medical practice and the complexities of hospital care, illuminates the emotional and cognitive aspects of caregiving and decision-making from the perspective of an active primary care physician, and offers behind-the-scenes portraits of hospital sanctums and the people who inhabit them.

Gut Check
Ryan Madanick, MD, ACP Member, is a gastroenterologist at the University of North Carolina School of Medicine, and the Program Director for the GI & Hepatology Fellowship Program. He specializes in diseases of the esophagus, with a strong interest in the diagnosis and treatment of patients who have difficult-to-manage esophageal problems such as refractory GERD, heartburn, and chest pain.

I'm dok
Mike Aref, MD, PhD, FACP, is an academic hospitalist with an interest in basic and clinical science and education, with interests in noninvasive monitoring and diagnostic testing using novel bedside imaging modalities, diagnostic reasoning, medical informatics, new medical education modalities, pre-code/code management, palliative care, patient-physician communication, quality improvement, and quantitative biomedical imaging.

Informatics Professor
William Hersh, MD, FACP, Professor and Chair, Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, posts his thoughts on various topics related to biomedical and health informatics.

David Katz, MD
David L. Katz, MD, MPH, FACP, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care.

Just Oncology
Richard Just, MD, ACP Member, has 36 years in clinical practice of hematology and medical oncology. His blog is a joint publication with Gregg Masters, MPH.

Kevin Pho, MD, ACP Member, offers one of the Web's definitive sites for influential health commentary.

MD Whistleblower
Michael Kirsch, MD, FACP, addresses the joys and challenges of medical practice, including controversies in the doctor-patient relationship, medical ethics and measuring medical quality. When he's not writing, he's performing colonoscopies.

Medical Lessons
Elaine Schattner, MD, FACP, shares her ideas on education, ethics in medicine, health care news and culture. Her views on medicine are informed by her past experiences in caring for patients, as a researcher in cancer immunology, and as a patient who's had breast cancer.

Mired in MedEd
Alexander M. Djuricich, MD, FACP, is the Associate Dean for Continuing Medical Education (CME), and a Program Director in Medicine-Pediatrics at the Indiana University School of Medicine in Indianapolis, where he blogs about medical education.

More Musings
Rob Lamberts, MD, ACP Member, a med-peds and general practice internist, returns with "volume 2" of his personal musings about medicine, life, armadillos and Sasquatch at More Musings (of a Distractible Kind).

David M. Sack, MD, FACP, practices general gastroenterology at a small community hospital in Connecticut. His blog is a series of musings on medicine, medical care, the health care system and medical ethics, in no particular order.

Reflections of a Grady Doctor
Kimberly Manning, MD, FACP, reflects on the personal side of being a doctor in a community hospital in Atlanta.

The Blog of Paul Sufka
Paul Sufka, MD, ACP Member, is a board certified rheumatologist in St. Paul, Minn. He was a chief resident in internal medicine with the University of Minnesota and then completed his fellowship training in rheumatology in June 2011 at the University of Minnesota Department of Rheumatology. His interests include the use of technology in medicine.

Technology in (Medical) Education
Neil Mehta, MBBS, MS, FACP, is interested in use of technology in education, social media and networking, practice management and evidence-based medicine tools, personal information and knowledge management.

Peter A. Lipson, MD
Peter A. Lipson, MD, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. The blog, which has been around in various forms since 2007, offers musings on the intersection of science, medicine, and culture.

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Janice Boughton, MD, FACP, practiced internal medicine for 20 years before adopting a career in hospital and primary care medicine as a locum tenens physician. She lives in Idaho when not traveling.

World's Best Site
Daniel Ginsberg, MD, FACP, is an internal medicine physician who has avidly applied computers to medicine since 1986, when he first wrote medically oriented computer programs. He is in practice in Tacoma, Washington.

Other blogs of note:

American Journal of Medicine
Also known as the Green Journal, the American Journal of Medicine publishes original clinical articles of interest to physicians in internal medicine and its subspecialities, both in academia and community-based practice.

Clinical Correlations
A collaborative medical blog started by Neil Shapiro, MD, ACP Member, associate program director at New York University Medical Center's internal medicine residency program. Faculty, residents and students contribute case studies, mystery quizzes, news, commentary and more.

Interact MD
Michael Benjamin, MD, ACP member, doesn't accept industry money so he can create an independent, clinician-reviewed space on the Internet for physicians to report and comment on the medical news of the day.

PLoS Blog
The Public Library of Science's open access materials include a blog.

White Coat Rants
One of the most popular anonymous blogs written by an emergency room physician.

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