Six weeks phylloquinone supplementation produces undesirable effects on blood lipids with no changes in inflammatory and fibrinolytic markers in postmenopausal women.

BACKGROUND

Cardiovascular disease is the major cause of death in the Western world, but some recent studies indicate that vitamin K may play a role in atherosclerosis protection.

OBJECTIVE

The aim of this study was to evaluate the effect of phylloquinone supplementation on blood lipids, inflammatory markers and fibrinolytic activity in postmenopausal women.

METHODS

Thirty-one postmenopausal women completed this placebo-controlled, randomized crossover study and received 500 microg phylloquinone or placebo in addition to their habitual diet during two periods of 6 weeks' duration. Blood concentration of lipids, inflammatory markers and fibrinolytic parameters were measured after each period.

RESULTS

Inflammatory markers, fibrinolytic parameters, total cholesterol and LDL-C were unaffected by the supplementation, whereas a 15% increase was seen in triacylglycerols (P = 0.015) and a 5% decrease in HDL-C (P = 0.06).

CONCLUSIONS

Six weeks supplementation with a dose of phylloquinone similar to that obtainable from the diet induced a deterioration of the lipid profile with no improvement in any of the other risk markers analysed. Thus, these results do not support a cardioprotective effect of vitamin K as has been suggested by others.