Combined effects of dietary fat and birth weight on serum cholesterol concentrations: the Hertfordshire Cohort Study.

BACKGROUND: Blood cholesterol responses to the manipulation of dietary fat vary widely between persons. Although epidemiologic evidence suggests that prenatal growth and nutrition influence adult cholesterol homeostasis, whether prenatal growth modifies the association between dietary fat intake and serum cholesterol concentration in adults is unknown. OBJECTIVE: The aim was to examine the relation between fat intake and serum cholesterol concentrations in men and women whose birth weights were known. DESIGN: We studied a cohort of men and women aged 59-71 y. Diet was assessed with a food-frequency questionnaire. Total, HDL-, and LDL-cholesterol concentrations and the ratio of HDL to LDL cholesterol were measured in fasting blood samples from 574 men and 562 women who did not have coronary heart disease. RESULTS: Total and saturated fat intakes were not associated with serum cholesterol concentrations in men or women. However, subdivision by birth weight showed associations in men but not in women. High intakes of total and saturated fat were associated with reduced HDL-cholesterol concentrations in men with birth weights < or =3.2 kg (7 lb) but not in men with higher birth weights. Similar effects on the HDL-to-LDL cholesterol ratio were observed (P for interaction = 0.02 for total fat and 0.01 for saturated fat). When 32 men taking cholesterol-lowering medication were excluded, the interactions were strengthened (P = 0.008 and 0.006, respectively). CONCLUSION: The adverse effects of high intakes of total and saturated fat on serum cholesterol concentrations in men may be confined to those with lower birth weights.