One possible cause for the increased prevalence of asthma is that breathing patterns associated with sedentary behavior could lead to developmental changes in children lungs.
In a birth cohort of more than 3000 children there was a linear trend for increased television viewing at 3.5 years to be associated with the development of asthma at 11 years.
Children with more than 2 hours of viewing per day were almost twice as likely to have asthma as those with only 1 to 2 hours of viewing. The outcome was independent of body mass and sedentary behavior at age 11.5 years (Thorax 2009;64:321-5).
News Beyond Our Pages. JACI, Volume 123, Issue 6, Pages 1197-1198 (June 2009).
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