Vitamin K2 May Reduce Heart Risk in Women

Vitamin K is a less understood vitamin, but recent research has shown that it is crucial to the health of men and women. It may provide benefits to bone, heart and prostate health and may help in the prevention of some diseases.

Vitamin K has two primary forms, vitamin K1 (phylloquinone) and the more bioavailable vitamin K2 (menaquinones). Vitamin K1 makes up about 90% of the western dietary intake of vitamin K. Vitamin K1 is available from dietary sources such as dark leafy greens like spinach, as well as cruciferous vegetables. Vitamin K2 consists of several forms referred to as menaquinones, and denoted scientifically as MK-n where the "n" describes the number of "prenyl groups" attached to the molecule. MK-4 is found in much lower levels in some types of red meat; MK-7, MK-8 and MK-9 are found in ripened cheese such as brie and blue cheeses.

A new study conducted in the Netherlands has found that Vitamin K2 may reduce the risk of developing coronary heart disease (CHD) in post-menopausal women.¹ The study involved 16,057 post-menopausal Dutch women, between 49 and 70 years of age, without cardiovascular disease at baseline. The women were part of the Prospect-EPIC cohort study and were enrolled between 1993 and 1997 and followed for an average of 8.1 years. Dietary intake of the K vitamins was assessed through food frequency questionnaires.

The researchers found that for every 10 microgram increase of K2 consumed there was a 9% decrease in risk of developing CHD. There was no benefit from vitamin K1 consumption. The researchers theorized that this may be due to the way the different forms are handled by the body. Vitamin K1 is almost immediately taken up by the liver, whereas the menaquinones circulate through the blood and are taken up through the blood vessel walls and bone tissue. The researchers noted that there appeared to be an even greater benefit from the longer-chain menaquinones, MK-7, MK-8 and MK-9. The researchers suggest that this could again be due to the time in circulation, "a stronger effect of the longer subtypes could be due to a slower hepatic clearance of these subtypes, making them longer available for carboxylation reactions."

The researchers warn that because ripened cheeses tend to be higher in saturated fat than other cheese, it may not be advisable to increase intakes of these food items as a way to increase your dietary intake of these menaquinone compounds. The researchers suggest increasing dietary intake in the form of a supplement.

Our HerHealth™ Complete Women's Multivitamin contains half of the USDA Daily Value for vitamin K in the form of vitamin K2. Learn more about HerHealth™ and all of our multivitamins here.

1. Gast, G. C., N. M. de Roos, et al. (2009). "A high menaquinone reduces the incidence of coronary heart disease in women." Nutr Metab Cardiovasc Dis.