Pollen grain

Pollen grain (Derek Berwin/Riser)

First-born child? Sorry about that.

The likelihood of food allergies shrinks the lower down in your family birth order your are, according to a study out of Kyoto University in Japan. Surveying of the parents of 13,000 children between ages 7 and 15, researchers found that 4 percent of first-borns suffered from food allergies, while 3.5 percent of second-borns and 2.6 percent of children born after that were allergic to certain foods.

Trying to avoid asthma? Ditch the incense, and grow up on a farm

Kids whose parents burned incense were 36 percent more likely to have current asthma and 64 percent more likely to wheeze when they exercised, according to a Taiwanese study in the European Respiratory Journal. Meanwhile, a study published in the New England Journal of Medicine shows that children on farms — where the bacteria population is far more diverse than in urban areas — were 30 percent to 50 percent less likely to have asthma than children who didn't live on farms. After testing dust in homes in both settings, researchers demonstrated that the wider the range of microbes in the houses, the less likely it was that the children would suffer from asthma. Why? Among the possible explanations for the findings: The beneficial bacteria that live around farms could be staving off some of the harmful bacteria that exacerbate asthma.

24.6 million

Americans have asthma, or just over 8 percent of the population, according to 2009 data (the most recent) from the Centers for Disease Control and Prevention.

17.5 million

are adults

7.1 million

are children

10.5%

Increased chances that women have over men of being diagnosed with asthma in their lifetime. They are three times more likely to be hospitalized for asthma, and report more severe symptoms, according to a research review in the journal Current Opinions in Pulmonary Medicine.

12.8 million

people in 2008 had an asthma attack

Unhappy together

Nuts and sesame: Researchers have linked a history of dual allergic reactions to peanuts and tree nuts with a 10-fold higher risk of allergy to sesame seeds — the tiny seeds that are commonly found in hummus and on hamburger buns. The study, published in Pediatric Allergy and Immunology, also reported that — despite being labeled by the FDA as a tree nut — coconut sensitization or allergy did not appear to be related to kids' reactions to peanut, tree nut or both.

Asthma and celiac disease: People with the digestive disorder celiac disease are more likely to develop asthma, according to a study in the Journal of Allergy and Clinical Immunology. Specifically, people with celiac disease were 60 percent more likely to develop asthma, relative to those without celiac. Those diagnosed with asthma were also more likely to eventually develop celiac disease, authors reported.

16 days

Increased length of the ragweed pollen season in 2009 compared to 1995 in Minneapolis, according to a study in the Proceedings of the National Academy of Sciences. As global average temperatures have warmed, the first frost has been delayed, especially at higher latitudes in the Western Hemisphere, which has meant a longer season for ragweed. Even in places where ragweed season was shortened slightly — such as Texas, Oklahoma and Arkansas — there was a lot more pollen, which caused more intense asthma and allergy symptoms, study authors said.



—From news services