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

Wednesday, April 1, 2015

Bambafication, or how consuming peanuts in infancy can help prevent peanut allergies

Food allergies are commonly misunderstood, so please bear with me while I first explain what food allergies are and are not. Various foods can cause all sorts of unpleasant effects. Most of these are not allergies. Allergies are only reactions caused by a specific antibody (called IgE) that results in hives, trouble breathing, or a life-threatening condition called anaphylaxis. So, if yogurt gives you diarrhea, that's not an allergy. It might be lactose intolerance. If coffee gives you palpitations, you're not allergic to coffee; you're having a side-effect from the caffeine. Ditto chocolate worsening your heartburn; not an allergy.

Of all foods that cause allergic reactions, peanut allergies are the leading cause of anaphylaxis and death, and the prevalence of peanut allergies in the U.S. has grown fivefold in the last 13 years, from 0.4% in 1997 to more than 2% in 2010. This increasing prevalence of a potentially life-threatening allergy has caused some schools to ban peanut products and has caused some airlines to stop offering peanuts in their snacks.

Believing that repeated exposure in infancy of allergy-causing foods leads to allergies, health officials in the UK in 1998 and in the U.S. in 2000 published guidelines recommending the exclusion of foods likely to cause allergies from the diets of infants at high risk of developing allergies. But subsequent studies failed to show that elimination prevented the development of allergies, so the recommendations were withdrawn in 2008. Since then, pediatricians have had no solid evidence on which to base recommendations, until now.

A study in the UK published this week in the New England Journal of Medicine (NEJM) enrolled 640 infants between the ages of 4 and 11 months who were considered to be at high risk for peanut allergy because they had severe eczema or egg allergies, or both. They were all given a skin-prick test to check for peanut sensitivity. The infants that had a severe reaction to the skin-prick test were excluded from the study. Infants who had no reaction or a mild reaction were enrolled and were randomized to 2 groups.

The parents of children in 1 group were told that their children should avoid peanut products. The parents of children in the second group were instructed to give their children at least 2 grams of peanut protein 3 times a week. (Their first exposure to peanut protein was done under medical supervision.)

The peanut source given to the infants in the study was Bamba, an extremely popular Israeli children's snack made from puffed corn and peanut butter. If you've spent any time in Israel around kids you've seen Bamba. Hilariously, the authors admit that “it was not possible to administer a placebo for Bamba because of financial and logistic constraints.” I can imagine the researchers desperately trying to figure out how to make something that looked and tasted like Bamba but without peanuts, and then giving up when they realized that that this would be more expensive and take longer than the rest of the study. The authors tell us that smooth peanut butter was supplied for those infants who didn't like Bamba, but intensive psychiatric testing would have been more appropriate, because Bamba is delicious.

The children were followed until they were 5 years old and then given a supervised oral challenge of peanut protein to test them for allergies.

The results were quite dramatic. Among the children who initially had no reaction to the peanut sensitivity skin-prick test, 13.7% (about 1 in 7) of the children who avoided peanuts became allergic, compared to 1.9% (about 1 in 50) of children who consumed peanuts. That means that for every 8 children who consumed peanuts 1 fewer child developed a peanut allergy.

The results in children who initially had a mild reaction to the skin-prick test were even more impressive. These children were at much higher risk of becoming allergic since their mild skin test result suggests that their immune system had already been partially sensitized to peanut protein. 35.3% (about 1 in 3) of the children who avoided peanuts became allergic, compared to 10.6% (about 1 in 10) of the children who consumed peanuts. That means that for every 4 children with a mildly positive skin test who consumed peanuts, 1 fewer child became allergic.

Recommendations will likely be updated to account for these findings. First, infants with no eczema or family history of peanut allergies are at low risk of developing allergies and should start eating peanut products as soon as they start eating solid foods. (Don't feed whole peanuts to infants. They're a choking hazard. Anyway, Bamba tastes better and now might be one of the most evidence-based snacks.) Infants who are at high risk for peanut allergy because of eczema, an egg allergy, or a family history of peanut allergy should have a skin test to check for sensitivity to peanut. Those who have a negative test can proceed with Bambafication. Those who have a positive test should have their first exposure to peanut product under the supervision of an allergist.

Learn more:
Exposing infants to peanuts causes big reduction in peanut allergy, study shows (The Washington Post)
Feeding Infants Peanut Products Could Prevent Allergies, Study Suggests (Well, New York Times health blog)
About-Face on Preventing Peanut Allergies (Wall Street Journal)
The LEAP Trial (NEJM Quick Take video)
Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy (NEJM article)
Preventing Peanut Allergy through Early Consumption — Ready for Prime Time? (NEJM editorial)

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. Holding privileges at Cedars-Sinai Medical Center, he is also an assistant clinical professor at UCLA's Department of Medicine. This post originally appeared at his blog.

Labels: , , , ,


Post a Comment

Subscribe to Post Comments [Atom]

<< Home

This is a printer-friendly version of this page

Print this page  |  Close the preview




Contact ACP Internist

Send comments to ACP Internist staff at

Blog log

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.

Why is American Health Care So Expensive?
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.

Powered by Blogger

RSS feed