Objectives. To examine if increased egg consumption raises serum high-density-lipoprotein (HDL) cholesterol in healthy individuals. Design. A cross-over study. Setting. A private clinic for preventive health examinations in Copenhagen. Subjects. Twenty-four healthy adults, 12 men and 12 women, aged 23-52 (median 40) years. Interventions. After a 1-week control period each person added two boiled eggs to the usual daily diet for 6 weeks. All persons were instructed not to change the lifestyle in other ways during the whole study period. Main outcome measures. Serum HDL cholesterol, total cholesterol and triglycerides were measured before, during and after 6 weeks of extra egg consumption. The corresponding serum low-density-lipoprotein (LDL) cholesterol was calculated from the Friedewald formula. Results. After 6 weeks of extra egg consumption serum HDL cholesterol increased by 10% (P < 0.05) and total cholesterol increased 4% (P < 0.05), whereas the ratio total cholesterol/HDL cholesterol did not change significantly. Serum triglycerides and LDL cholesterol were also unchanged. Conclusions. A moderate egg intake should not be rigorously restricted in healthy individuals.