An apple a day...

Äpfel während der Schwangerschaft zu essen lohnt sich - das Kind wird dadurch gegen Atemwegserkrankungen und Asthma weniger anfällig; ißt die Mutter darüber hinaus noch öligen Fisch, wird das Auftreten von Ekzemen reduziert...
Mit den Äpfeln wird das klappen, aber mit dem "öligen Fisch"?

An apple a day keeps the wheeze (=Keuchen, schwer Atmen) away
A study of a cohort of pregnant mothers from Aberdeen followed for over five years has found that consumption of apples during pregnancy may protect the child against wheeze and asthma; maternal intake of oily fish during pregnancy (as has been shown previously) may reduce the incidence of eczema.
The findings are from 1253 mother-child pairs originally recruited during pregnancy, when the mothers completed a dietary history and were tested for atopy. Maternal food intake in pregnancy that had no effect on the frequency of diagnosis of respiratory and atopic symptoms in their 5 year olds included total fruit intake, fruit juice, kiwi fruit, total vegetables, green leafy vegetables, whole grains, dairy fat, and margarine.
The authors say that the benefit from apples may relate to their content of flavonoids, which are powerful antioxidants.
References
Thorax 2007 doi: 10.1136/thx.2006.074187