Salt intake is the biggest risk factor in the development of asthma in children.

Too much television 'is an asthma risk'
article in the Telegraph

Extract:

"The study of 20,000 six and seven-year-olds, published in the medical journal Epidemiology, confirmed a strong link with asthma and obesity, but found that salt was the biggest risk. Those with the highest intake were two and a half times more likely to develop asthma."

The main cause of obesity in children is, of course, eating salt and salty food. - See http://www.wildeaboutsteroids.co.uk/children.html