Serum cholesterol level in infancy is inversely associated with subsequent allergy in children and adolescents. A 20-year follow-up study

Background Previous studies suggest an association between an altered lipoprotein profile and atopy. The association has been hypothesized to be due to alterations in the dietary fat intake, a factor possibly contributing to the increase of allergic diseases in industrialized countries. Objective We aimed at assessing whether there is an association between the serum lipid levels in infancy and subsequent development of allergic symptoms in childhood and adolescence. Methods A cohort of 200 unselected newborns was prospectively followed up from birth to age 20 years (from 1981 to 2002) with repeated measurements of total cholesterol from birth and throughout the first year of life. The subjects were re‐examined at the ages of 5, 11 and 20 years, with assessment of the occurrence of allergic symptoms, skin prick testing (SPT) and measurement of total IgE and of the total, high‐ and low‐density lipoprotein cholesterol. Results Children and adolescents with allergic symptoms, SPT positivity and an elevated IgE had lower total cholesterol levels in infancy and childhood than the non‐atopic subjects. The difference was not detectable in cord blood, but became significant from age 2 months onward. Conclusion The inverse association between the cholesterol level in infancy and subsequent manifestations of atopy seems not to be due to atopy‐related dietary alterations, because it was already present in early infancy, when virtually all the infants were on a similar diet, i.e. on exclusive breastfeeding.