“We found a direct increase in the number of atopic [allergic] diseases associated with obesity in urban female children and teenagers, but not in males,” said study co-author Dr. Sairaman Nagarajan. He’s a resident physician in the department of pediatrics at SUNY Downstate Medical Center in New York City.
“These results were highly significant, even after adjusting for the effects of age and race,” he said.
Their investigation focused on 113 children (45 percent girls, 55 percent boys), about a quarter of whom were obese.
All the children lived in Brooklyn, N.Y., and were on average between the ages of 8 and 9. Allergies aside, all were deemed to be relatively healthy.
Medical histories were taken to assess for a range of allergic conditions, including asthma, food allergies, hay fever and/or eczema. The children were then given allergy scores, with those struggling with more allergic conditions getting higher scores.
The researchers found that obese girls had allergy scores higher than normal-weight girls: 4 vs. 2.6.
In contrast, obese boys were found to have slightly lower allergy scores than normal-weight boys: 3 vs. 3.4.
The upshot, said Nagarajan, is the possibility “that lifestyle modification therapies and exercise and diet programs may be specifically beneficial to urban obese girls.”
“We hypothesize that there are hormonal differences causing girls to have higher atopy [allergies],” said Nagarajan.
For example, he pointed to the possibility that higher adrenal sex hormone levels found among girls may predispose them to a higher risk for both becoming obese and also for having a stronger overall inflammatory response.