Early introduction of cereals into children's diets as a risk-factor for grass pollen asthma

Background The prevalence of asthma has increased from the 1950s to the 199 0s. The relationship between diet and asthma is an area of controversy that has never been fully evaluated. Attempts at dietary prevention of asthma h ave produced conflicting results. We have recently identified allergens fro m cereals that show cross-reactivity with proteins in grass pollen. An earl y intake of cereals in the diet during early life might cause IgE sensitiza tion to cereals. It is not known whether such sensitization predisposes the development of allergy to pollen. Methods To test this hypothesis, a cross-sectional study and an observation al case-control analysis of reviewed data were carried out on 16381 patient s who had been admitted to our Allergy Unit between 1989 and 1999. All the patients underwent allergy tests to identify asthma risk-factors. Ali infor mation in our data base was analysed using the SPSS computer system. Results There has been an increase of 7.8% in incidences of allergic asthma and a 7.3% increase in asthma due to grass pollen in the last decade. Gras s-pollen asthma was associated with sensitization to cereals. The early int roduction of cereals in the diet of children was found to be a risk factor for grass-pollen asthma (OR = 5.95; 95% CI 3.89-9.10). Conclusions These findings document the progression of allergic asthma duri ng a decade in a large sample of people who were influenced by similar envi ronmental conditions and studied with the same diagnostic methods. This stu dy represents the largest database of patients in which a common food is sh own to be a risk factor for asthma.