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Could childhood ear infections be contributing to the obesity epidemic?

New research points to a possible link between the two common conditions, suggesting that children who suffer from moderate to severe middle ear infections are at an elevated risk of becoming overweight later in life.

John Hayes of Brown University in Providence, R.I., noted that the chorda tympani nerve, which is involved in taste sensations, runs through the middle ear as it passes from the tongue to the brain. Some researchers suspect that repeated ear infections may damage the nerve and change taste sensations.

"The theory is that damage to the nerve, due to ear infections, somehow alters the perception of food ... so that the person is more likely to enjoy high-fat and sweet food and possibly drink more alcoholic beverages," Dr. Hayes said in an interview. "All these foods are energy dense and increase the risk of becoming obese."

Dr. Hayes was among a group of experts who gathered at the annual convention of the American Psychological Association in Boston yesterday to consider the latest evidence.

Linda Bartoshuk of the University of Florida's college of dentistry released preliminary data indicating that middle ear infections, known medically as otitis media, increase the preference for high-fat foods.

Howard Hoffman of the U.S. National Institutes of Health in Bethesda, Md., presented a study showing that children who had their tonsils removed were more likely to be overweight. Tonsillectomies were once a common treatment for chronic ear infections.

And yet another study found that kids with a history of ear infections ate fewer vegetables and more sweets.

Cases of middle ear infections have crept up in recent decades, paralleling the rise in obesity, said Kathleen Daly of the University of Minnesota, Twin Cities. But there is now a vaccine to protect kids from the malady. That could bode well for helping to bring obesity under control, Dr. Daly said.

The scientists cautioned that more research is needed to confirm the findings and stressed that obesity is a complex issue involving many factors. "This might be only one small piece of a larger puzzle," Dr. Hayes said.

Allergy misery

Stress and anxiety can intensify allergy attacks, according to U.S. researchers.

For their study, they subjected allergy sufferers to a battery of tests to measure their symptoms under different conditions. When the volunteers were placed in a stressful situation - such as giving a public speech - their reaction to allergens was greater than normal and their symptoms lasted longer.

"Stress makes it a lot worse," said one of the researchers, Jan Kiecolt-Glaser of the Ohio State University.

Gailen Marshall, a co-investigator on the study at the University of Mississippi, said the body under pressure will release stress hormones, such as catecholamines, which can add fuel to the already overactive immune system of an allergy sufferer.

The obvious lesson from the study is that allergy sufferers need to keep their stress and anxiety levels under control. "Stress management doesn't have to be a whole lot of hocus-pocus," Dr. Marshall said. Common sense practices - including good nutrition, regular exercise, sufficient sleep and a positive attitude - "can make a tremendous difference in the ability of an individual to withstand the stress of everyday life," he said

Taking medications, such as antihistamines, as a preventive measure during allergy season is a good idea, too. Once the symptoms begin, they can be hard to get back under control, he said.

One study to ignore

Some health scares just aren't worth worrying about.

For instance, researchers at Rutgers University in New Jersey yesterday released a study indicating that the use of moisturizing creams can trigger skin cancer in mice.

The team tested four different brands of moisturizing cream on mice that were exposed to heavy doses of cancer-causing ultraviolet light. The mice smeared with the various commercially available creams currently on the market developed more skin cancers than mice treated with a custom blend cream created by the researchers, according to the findings published in the Journal of Investigative Dermatology.

This is a classic example of what's bad for laboratory mice may not necessarily be harmful to people. In fact, the mice used in the study were a genetically altered hairless variety prone to get cancer. What's more, they were exposed to far higher doses of UV than most people would receive in a lifetime, according to independent experts who have looked at the study.

"This has no relevance to causation of human skin cancer and does not prove in any way whatever that moisturizing creams are cancer-causing in humans," Gordon McVie of the European Institute of Oncology told Agence France-Presse.

Aside from the science, there are also financial interests to consider. A study footnote discloses that "a patent application for the custom blend cream was filed on behalf of Rutgers and Johnson & Johnson." The consumer products' giant and the researchers could be positioning themselves to market a moisturizing cream that is apparently free of skin cancer risk - at least for laboratory mice.