High birth weights in prewar Faroe Islands.

Birth weights in the Faroe Islands are among the highest in the world. During the 1980s, infants born there had 200 grams higher mean birth weight than their Danish peers. Half of this diVerence could be attributed to a longer gestation (four days on average), half to a higher fetal growth rate. A high intake of seafood has been suggested to be a possible cause of this pattern. The findings of four days longer mean gestation and 100 grams higher mean birth weight in Danish women who received fish oil during pregnancy only partially corroborated this hypothesis, as no eVect was detected on fetal growth. However, several observational studies have exhibited direct associations between fetal growth rate and fish intake, and this suggests that factors in seafood other than the oily part might play a part. We hypothesised that if the cause(s) of the higher birth weights in the Faroes indeed are to be found in the traditional Faroese life style, we would find even higher birth weights before the second world war than today, because the way of life there changed dramatically after the war towards that of other Western societies.