Summary
The effects of stearic acid (Cl8:0) and trans fatty acids on variables related to coagulation and fibrinolysis were studied in
80 healthy humans average age 29 ± 9 years. All subjects consumed a baseline diet
high in saturated fatty acids, mainly from dairy fat for 5 weeks. After this baseline
diet they were allocated either to a diet high (8.7% of energy, En%) in trans fatty acids from partially hydrogenated vegetable oil (40 subjects) or a diet high
(9.3 En%) in stearic acid (40 subjects) for 5 weeks. All diets contained 32.2-33.9
En% fat, 14.6-15.8 En% saturated plus trans fatty acids, 12.2-12.5 En% cis-monounsaturated and 2.9-3.5 En% polyunsaturated fatty
acids and 216-250 mg/10 MJ cholesterol. The fats were mixed into solid foods and almost
all daily food was provided.
In comparison with the baseline dairy fat diet no change was observed in the concentrations
of plasma fibrin degradation products and D-dimers. Also the factor VII coagulant
activity (F VII :C), tissue type plasminogen activity (tPA) and plasminogen activator
inhibitor activity (PAI-1) were not affected by the experimental diets. Small increase
in plasma fibrinogen concentration during the stearic acid diet was statistically
significant (from 3.49 to 3.63 g/1; p = 0.041), but probably without any biological
significance. Both diets increased plasma level of lipoprotein Lp(a). It can be concluded
that as far as coagulation and fibrinolysis are concerned there is no need to differentiate
between stearic acid or trans monoenoic fatty acids.
