Against the background of reported different trends of incidence and presentation of coeliac disease in Sweden and Finland, a joint study was done to explore potential causes. The clinical study confirmed that classical symptoms and diagnosis before 2 years of age dominated in Sweden. In Finland, the symptoms were more diffuse and diagnosis in most cases was made after the age of 8 years. A significantly lower weight score attained at diagnosis was seen in Swedish patients compared with Finnish. No significant difference in HLA expression was found. Infant feeding was investigated by studying food records of healthy infants. Swedish infants ingested three times more wheat protein at 9 months and twice as much at 12 months compared with Finnish children. It is concluded that the intake of infant cereal protein might influence when and how clinical coeliac disease appears. The question whether or not it is important for if coeliac disease will be acquired still remains to be answered.