Increased linoleic acid/α-linolenic acid ratio in Swedish cord blood samples collected between 1985 and 2005.

Background: Cord serum (CS) phospholipid fatty acid composition is associated with maternal diet during foetal life, and maternal intake of linoleic acid (LA, C18:2ω-6) and α-linolenic acid (LNA, C18:3 ω-3) has been shown to influence the LA and LNA levels in CS. A possible connection between the increased incidence of atopic diseases and increased intake of LA and decreased intake of LNA in the Western world has been proposed.
Aim: The aim of this study was to explore phospholipid fatty acid proportions and total IgE levels in CS from Swedish children, collected from 1985 to 2005, a period with increasing frequency of allergic diseases in Sweden, and reveal possible changes over time.
Method: Phospholipid fatty acids and total IgE antibodies were analysed with gas chromatography and UniCAP(®) technology, respectively, in 300 CS samples.
Results: The proportions of LA and LNA decreased significantly from 1985 to 2005 (p < 0.001 for both). However, the LA/LNA ratio did increase (p < 0.001), revealing a relatively larger decrease in LNA than in LA. No correlations were found between ω-6 and ω-3 fatty acids and total IgE antibodies in CS from newborn children.
Conclusions: The LA/LNA ratio increased (p < 0.001) in cord serum samples collected between 1985 and 2005, and no correlations between fatty acids and total IgE were found.