On the within-population relationship between nutrition and serum lipids: the B.I.R.N.H. study.

A randomized study was performed in Belgium concerning the relationship between diet and serum lipids in 5485 men and 4856 women with a mean age of 49 years. In men 17.3% of total energy was provided by saturated fat, 15.2% by monounsaturated fat and 7.5% by polyunsaturated fat. The fat intake in women was very similar. The P/S ratio was 0.51 in men and 0.52 in women. The alcohol intake was significantly higher in men (5.2% of total energy) than in women (2% of total energy). In men and women total serum cholesterol increased with saturated fat intake (p less than 0.001) and decreased with polyunsaturated fat intake (p less than 0.01). Saturated fat intake raised the HDL-cholesterol level in men and women (p less than 0.001) and monounsaturated fat raised it in men only (p less than 0.01). Dietary cholesterol increased the HDL-cholesterol level in women only (p less than 0.01). HDL-cholesterol increased with alcohol consumption (p less than 0.001) and decreased with cigarette smoking (p less than 0.001). All these changes were adjusted for differences in age, height and weight. The study confirms the existence, within a population, of a significant relationship between fat intake and serum lipid levels.