Cod liver oil intake linked to asthma

Researchers analysed more than 17,000 adults who were free of asthma at the start of the study and followed them for 11 years to 2008.

Those who had a daily intake of cod liver oil were found to have a 62% greater chance of developing incident asthma, which the authors believe was due to the previously high concentration of vitamin A in the oil (1000µg per 5ml) in Norway.
Thorax 2012; online 13 Sept