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

Wednesday, November 9, 2011

It's time to kill the multivitamin

You have likely heard about a recent study, involving roughly 40,000 women over the age of 60, in which daily use of a multivitamin and several other nutrient supplements was associated with a higher rate of death. Along with the mix of shock, consternation, and disappointment is the very practical question: could a multivitamin kill you?

Boredom by Furryscaly via Flickr and a Creative Commons licenseAlmost certainly not! The current study, like others before it that have hinted at much the same association, is absolutely NOT cause for panic. For each such study, there is another showing no real harm. That vial of (now menacing) multivitamins in your medicine cabinet doesn't mean you need to fast track the preparation of your will and testament.

For starters, the study now making headlines, and the similar studies preceding it, are observational. A large group of people is simply followed and assessed over time, and the associations between what they do, and what happens to them, are analyzed.

In the current case, routine use of a multivitamin was associated with roughly a 2% greater chance of dying over a 20-year span for women over age 60. So, for starters, a 2% increased risk of dying over 20 years is not exactly cause for panic, especially when one considers that dying in our early 80s is not entirely unexpected or untimely.

But even more important, these women were not assigned to a multivitamin or placebo; they made up their own minds. Some chose to take nutrient supplements, some did not. How did these two groups differ? Like all good observational studies, this one attempted to account for obvious differences in education, income, smoking status, general dietary pattern, and so on, but the only honest answer is: we don't know! We can't possibly know all the ways women who opt to take nutrient supplements differ from those who don't. (That, by the way, is why randomized trials can be so important; they reliably correct for this limitation of observational studies.)

So, for instance: What if women more concerned about a family history of chronic disease were the ones to take supplements? What if women who were less confident in their ability to eat fruits and vegetables daily were the ones to take supplements? What if women who were just more anxious and pessimistic about their health were the ones to take supplements? Independent of all other factors, pessimism increases mortality, and optimism decreases it.

We don't know that any of these "what ifs" was true; but if any one of these, or another like them, was true, it might be the reason for the (minimally) higher death rate among supplement users, rather than the supplements per se.

But, the fact of the matter is that several large studies now suggest possible harm attached to the use of multivitamins and certain other supplements (including some B vitamins, and iron). Since we never had any clear evidence of benefit from multivitamin use, and since the "at least it couldn't hurt" rationale for using multis as an insurance policy is clearly not valid, the day of the conventional multinutrient supplement is over. I used to take a multi, and no longer do; I used to recommend them to patients, and no longer do.

How could a mix of nutrients known to be essential cause harm? When we extract nutrients from their context in food, we are "guessing" about preparation, dose and combination. Errors in any of these could lead to trouble.

Imagine, for example, that you had all the essential construction material you needed to build a house but in the wrong proportion. Too many roofing shingles, but too little lumber. Or perhaps the beams were too short for the dimensions of the roof. We use nutrients to build cells and proteins and hormones every day, and having the right "stuff" but in the wrong form or supply could make a mess of things.

Or, consider a musical analogy. You love a jazz ensemble, a rock band and a symphony orchestra. Imagine the sax player from the one, the guitarist from the other, and the cellist from the third each playing her own music, all at the same time. Noise! Lovely on their own, a mess when combined badly.

This could be the case with how we have approached nutrient supplementation. Frankly, I don't know for sure--nobody does--but the potential for real, if modest, harm is plausible.

So what do we do now?

For one thing, we should recall that all along, the best-case scenario was "supplement," not substitute. There is no substitute for eating well, and that deserves our dedicated commitment.

At this point, unless you are likely to have a serious deficiency in overall nutrient intake, or unless you have a specific indication for taking a multivitamin, such as pregnancy or the intent of pregnancy, use of a multivitamin seems ill advised. You need a good reason to do it; "what the heck" is no longer sufficient.

Judicious use of select supplements still makes sense. We have convincing evidence of known or likely benefit from supplemental omega-3 oils and vitamin D for most men and women, and calcium for most women. For the most part, other supplements should be used for a specific reason, and with input from someone with genuine expertise. As an example, B12 supplementation is warranted for most vegans, and for all older adults with pernicious anemia. Let's not toss out the baby with the bathwater!

Another intriguing consideration is the use of whole food-based supplements (for example). Such products are "humble" in the sense that they don't presume to know how to combine nutrients, they let nature do it. They simply compress the nutrients from healthful foods into pill form so that those who don't eat quite as they should, including children, can fill in the gaps. We need more science to prove the benefits of such supplements, but the approach makes sense to me, and may prove to be the new-age answer to the multivitamin/mineral supplement.

Independent of other factors, a multivitamin is very, very unlikely to kill anyone. If there is risk attached to the use of such supplements, it is very small. But there may be some risk, and there is no reliable indication of benefit.

That's really all we need to know to conclude: it's probably time for us to kill the multivitamin.

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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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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