According to Australian researchers, campaigns to reduce heart disease by promoting polyunsaturated margarines and cooking oils could be partly responsible for the recent dramatic increase in childhood asthma in the developed world, reports New Scientist.
The research is published in Thorax , the Journal of the BritishThoracic Society.
They found that a diet high in polyunsaturated fats more than doubles a child's risk of asthma.
Polyunsaturated fats are found in sunflower and vegetable oil.
They contain high levels of omega-6 fatty acids, which can boost inflammation of tissues in the body.
This is one possible explanation for the link with asthma, says a team led by Michelle Haby of the Royal Children's Hospital in Melbourne.
"But at this stage, children should not be changing their diet," Haby told New Scientist.
"We do not know whether changing the diet will reduce the risk or severity of asthma - that is the subject of ongoing investigation."
The role of changing dietary fat habits on the recent increase in asthma is also unclear, she says.
"I expect the increase in asthma is due to a combination of factors, one of which may be diet."
Martyn Partridge, medical adviser to the UK's National Asthma Campaign, says: "This new evidence that suggests a reduction in consumption of polyunsaturated fats may also reduce the likelihood of developing asthma is helpful, but we are still a long way from being able to explain why this common disease is becoming more common."
More work is now required to establish the role of dietary polyunsaturated fat on asthma, says Hoby.