Dose-dependent effect on serum cholesterol and apoprotein B concentrations by consumption of boiled, non-filtered coffee

The effects of boiled coffee (BC) and filtered coffee (FC) on serum lipoproteins were compared in 41 healthy subjects whose serum cholesterol concentration was less than 7 mmol/l. The subjects consumed in random order BC and FC for 4-week periods in a crossover design. The individual daily consumption ranged from 2 to 14 cups (mean 5.7 cups per day) and was similar during both study periods. The serum total and LDL-cholesterol and apoprotein B concentrations were higher ( P < 0.001) and HDL-cholesterol lower ( P < 0.05) after BC than after FC. Bodyweight, apoprotein A-I and triglycerides remained unchanged. In the 16 subjects who consumed coffee < 5 cups per day the difference in serum total cholesterol between the BC and FC periods was non-significant ( P = 0.16). The differences in serum total cholesterol and LDL-cholesterol between the periods showed significant linear correlations with the amount of coffee consumed daily ( r = 0.52, P < 0.001 and r = 0.33, P < 0.05, respectively) but no association was found between the difference in HDL-cholesterol and the amount of coffee ( r = 0.14, P = 0.39). The results indicate a dose-dependent increasing effect on serum total and LDL-cholesterol and apoprotein B concentrations of boiled coffee.