EFFECT ON BLOOD-LIPIDS, COAGULATION, AND FIBRINOLYSIS OF A FAT HIGH IN MYRISTIC ACID AND A FAT HIGH IN PALMITIC ACID

The hypothesis that myristic acid (C14:0) has a stronger cholesterol-i ncreasing potential than does palmitic acid is based on very few exper imental observations. A randomized, strictly controlled dietary study was therefore designed to investigate the effect of a synthetic fat th at was high in myristic acid, and palm oil, which is high in palmitic acid, on lipoproteins and hemostatic variables. Twelve men were served two diets (40% of energy as fat) with 41% of fat as myristic (diet M) or palmitic acid (diet P) for 3 wk with 1 mo between the two dietary schedules. Plasma HDL cholesterol was 8% higher with diet M than with diet P: 1.10 +/- 0.06 (($) over bar x +/- SEM) vs 1.01 +/- 0.05 mmol/L (P < 0.006). Diet M raised factor VII coagulant (F VIIc) activity to 98% (77 - 117%) vs 96% (71 - 109%) (medians and ranges) after diet P ( P = 0.02). Total and LDL-cholesterol concentrations did not differ bet ween the diets. In conclusion, the myristic acid test fat was not more cholesterolemic than was palm oil, but it did induce a minor rise in F VIIc activity.