'Smokers causing all-year asthma'
Children with asthma are twice as likely to face attacks all-year-round if their parents or guardians smoke, says research from the US.
Even though parents knew that smoke could start attacks, 13% still did it.
The US researchers said it was "astounding" that parents were still smoking around asthmatic children.
About 5.1 million people in the UK have asthma, and attacks are often kicked off by dust or pollen, depending on different times of the year.
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"It's not rocket science, since it's well known that second-hand smoke can trigger asthma in children," said Kathryn Slish from the University of Michigan.
"But it's astounding that so many parents smoke around their asthmatic kids, and don't stop even though their children are having trouble breathing all year."
Other research, which marked World Asthma Day on Tuesday, showed that one in five children with asthma were not getting enough exercise because their parents were worried about them getting sick.
But experts at Asthma UK said that, except for the most severe asthma symptoms, children should exercise to help cope with it.