Giving babies fish oil supplements could help prevent them coughing and even developing asthma, an Australian study says.

The Childhood Asthma Prevention Study, led by researchers from the University of Sydney, has found giving children tuna fish oil is more effective in preventing asthma symptoms than getting them to avoid house dust mites.

Children at risk of asthma who were given daily doses of omega-3-rich fish oil from the age of six months had 10% less coughing by the time they were three. Those who were actively kept away from house dust mite allergens had a 7% drop in coughing symptoms.

The study, funded by the National Health and Medical Research Council, recruited 616 children from before birth at six Sydney hospitals.

The children, considered to be at high risk of asthma because of a family history and other factors, were monitored to see how many developed allergic disease.

The doctors did the study because they said previous research had suggested a possible benefit in keeping children away from house dust mites.