Is there any need to take extra vitamin k?

No: Most do not require extra vit k. Vit k may be beneficial for a select group of patients - those with intravenous feedings, those with malabsorption and those on long term antibiotics. Sometime pts with difficult to control INR while on Coumadin (warfarin) are given low dose vit k to help regularize their numbers.

Yes: Most peope are deficient in most nutrients including k. There is a lot of evidence that suggests that adequate k may help prevent arterial calcification and atherosclerosis. It is also essential in bone health to prevent osteoporosis. May be cancer protective.