Prospective study of serum cholesterol levels during first year of life.

A longitudinal prospective study of serum cholesterol concentrations during the first year of life has been carried out in 302 healthy babies. The results show that serum cholesterol estimations in cord blood cannot be used as a screening test for the diagnosis of familial hypercholesterolaemia. The only child subsequently found to have the condition had a cord serum cholesterol of 85 mg/100 ml compared with the mean value for the group of 78 mg/100 ml. The babies who had cord values greater than 100 mg/100 ml had values distributed throughout the normal range when re-examined at 1 year of age. Serum cholesterol concentrations during the early months of life were markedly influenced by the type of milk fed; it is suggested that investigations to establish the diagnosis of familial hypercholesterolaemia are deferred until the child is about 1 year old and feeding with cows' milk and mixed diet is established.Values obtained for serum cholesterol concentrations (mg/100 ml, mean +/- 1 S.D.) in healthy infants in this study were: at birth 78 +/- 23, at 1 week 155 +/- 31, at 6 weeks 155 +/- 31, at 4 months 184 +/- 36, at 8 months 195 +/- 37, and at 1 year 191 +/- 36.