Published online by Cambridge University Press: 09 March 2007
1. Four hundred and fifty patients who were treated for megaloblastic anaemias in northern Finland were grouped according to the month of diagnosis.
2. Only slight seasonal variation was detectable in the occurrence of megaloblastic anaemia.
3. During the first half of the twentieth century the seasonal variation in occurrence of megaloblastic anaemia was pronounced. The decrease in the variation is most likely related to the more even distribution throughout the year of the supply of foods containing folate and vitamin B12.