A new study indicates there may be yet another reason to reduce
childhood obesity — it may help prevent allergies. The study published
in the May issue of the Journal of Allergy and Clinical Immunology
showed that obese children and adolescents are at increased risk of
having some kind of allergy, especially to a food. The study was funded
by the National Institute of Environmental Health Sciences (NIEHS) and
the National Institute of Allergy and Infectious Diseases (NIAID), both
parts of the National Institutes of Health.
"We found a positive association between obesity and allergies," said
Darryl Zeldin, M.D., acting clinical director at NIEHS and senior author
on the paper. The researchers analyzed data on children and young adults
ages 2 to 19 from a new national dataset designed to obtain information
about allergies and asthma. "While the results from this study are
interesting, they do not prove that obesity causes allergies. More
research is needed to further investigate this potential link," Zeldin
The study is the first to be published using new data from the National
Health and Nutrition Examination Survey (NHANES). NHANES is a large
nationally representative survey conducted by the National Center for
Health Statistics, a part of the Centers for Disease Control and
Prevention. NHANES is designed to assess the health and nutritional
status of adults and children in the United States. An allergy/asthma
component was supported by NIEHS and added to the 2005-2006 NHANES
study, making it the largest nationally representative dataset of
allergy and asthma information ever assembled in the United States.
"We have all the pieces of the puzzle in this dataset," said Zeldin.
"The allergy and asthma component of NHANES provides allergen exposure
information, allergic sensitization information, as well as disease
outcome information. There is a wealth of knowledge we will be able to
gain by analyzing these data that will be useful to allergy and asthma
In this study, the researchers analyzed data from 4,111 children and
young adults aged 2-19 years of age. They looked at total and
allergen-specific immunoglobulin E (IgE) or antibody levels to a large
panel of indoor, outdoor and food allergens, body weight, and responses
to a questionnaire about diagnoses of hay fever, eczema, and allergies.
Obesity was defined as being in the 95th percentile of the body mass
index for the child's age. The researchers found the IgE levels were
higher among children who were obese or overweight. Obese children were
about 26 percent more likely to have allergies than children of normal
"The signal for allergies seemed to be coming mostly from food
allergies. The rate of having a food allergy was 59 percent higher for
obese children," said NIEHS researcher Stephanie London, M.D., a
co-author on the study.
"As childhood obesity rates rise, NIEHS will continue to work to
determine how environmental factors affect this epidemic," said Linda
Birnbaum, Ph.D., NIEHS director. "Seeing a possible link between obesity
and allergies provides additional motivation for undertaking the
challenge of reducing childhood obesity."
"Given that the prevalence of both obesity and allergic disease has
increased among children over the last several decades, it is important
to understand and, if possible, prevent these epidemics," said Cynthia
M. Visness, Ph.D., lead author on the paper and a scientist at Rho
Federal Systems Division, Inc. in Chapel Hill, N.C.
NIAID conducts and supports research — at NIH, throughout the United
States, and worldwide — to study the causes of infectious and
immune-mediated diseases, and to develop better means of preventing,
diagnosing and treating these illnesses. News releases, fact sheets and
other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov .
Visness CM, London SJ, Daniels JL, Kaufman JS, Yeatts KB, Siega-Riz AM, Liu AH, Calatroni A, Zeldin DC. Association of obesity with IgE levels and allergy symptoms in children and adolescents: Results from the National Health and Nutrition Examination Survey 2005-2006. Journal of Allergy and Clinical Immunology. May, 2009. Doi:10.1016/j.jaci.2008.12.1126.