Objective: To assess the effects of a low calorie diet on plasma lipids according to the Hind III polymorphism of the lipoprotein lipase (LPL) gene in overweight patients.
Design: Diet intervention study (25% restriction in energy intake during 2.5 months) in relation to genetic factors.
Subjects: 115 unrelated patients (77 women and 38 men) recruited on the basis of 120% of ideal body weight.
Measurements: Body weight, body mass index, blood lipids and lipoproteins, at entry and after 2.5 months, determination of LPL Hind III genotypes.
Results: On spontaneous diet, lipid and lipoproteins differed significantly between Hind III genotypes. Homozygous subjects for the presence of the Hind III cutting site, H2H2, had significantly higher plasma and VLDL triglyceride and apolipoprotein B concentrations than subjects carrying H1 allele. H2H2 subjects reduced their VLDL-triglyceride and apolipoprotein B concentrations more than H1 carriers, in such a way that differences in lipid levels according to genotypes were no more significant after diet. The magnitude of the decrease in triglycerides was positively correlated with the initial concentration but, among hypertriglyceridemic subjects, H2H2 still had the largest decrease in plasma and VLDL-triglycerides.
Conclusion: The genetic variation at the LPL gene locus affects the response of serum lipid levels to caloric restriction. Overweight subjects with the H2H2 genotype of the LPL Hind III polymorphism are predisposed to hypertriglyceridemia but they are good responders to diet in terms of lipid levels.