Vitamin K2

Dr Thanh-Tam Pham - 01/01/2022

This a summary of the book “Vitamin K2: the Missing Nutrient for Heart and Bone Health” by Dr Dennis Goodman. Dr Goodman is a cardiologist and Clinical Professor, Department of Medicine at NYU Grossman School of Medicine.

Vitamin K2 is part of the vitamin K family, a group of fat-soluble vitamins. There are two groups: Vitamin K 1 has 1 molecule and is a Phylloquinone and K2 has multiple molecules known as menaquinones.

The basics of Vitamin K2:

         ●   Vitamin K2 can render special proteins (vitamin K dependent proteins) functional by the addition of carboxyl (-COOH) groups.

         ●   Vitamin K2 is needed for normal blood coagulation

         ●   Vitamin K2 is made by bacteria, which give fermented foods like cheese and the Japanese natto (fermented soybean) a high vitamin K2 content.

         ●   Vitamin K2 is also involved in bone formation and repair.

         ●   Vitamin K2 is associated with reduced risk for heart disease and hip fractures,

         ●   Vitamin K2 has been shown to inhibit calcium deposits (ie calcification) in blood vessels and even improve arterial flexibility.

The length of the side chain dictates Vitamin K2 ‘s ability to reach different tissues within the body. The longer the side chain, the more effective the form of vitamin K2. It will be absorbed better, stay in the blood longer and will be more active in bone, tissues and arteries. Vitamin K2 as MK7 has a long half life.

Vitamin K2 can play a major role in reducing blockages caused by atherosclerosis.

Mechanism of action:

Calcium accumulation is influenced by MGP (matrix Gla protein), a key inhibitor of vascular calcification. For MGP to bind calcium, and thus keep it away from arteries, it needs to be activated by vitamin K2. MGP contains glutamic acid (Glu) residues that is transformed to gamma-carboxyglutamate (Gla) by the enzyme gammaglutamyl carboxylase that needs vitamin K2 as a co factor.

Gla binds calcium ions and ensures that calcium is deposited in the bones, where it needs to be. It keeps calcium away from the heart and the blood vessels, where it could cause damage.

A study of 4,807 individuals age 50 and older showed a reduction in risk of cardiovascular disease and cardiovascular related deaths by 50 percent for those who ingested more vitamin K2.

To measure the activity of vitamin K2, it can be done indirectly by measuring Osteocalcin- another K dependent protein. If osteocalcin levels are undercarboxylated, it indicates vitamin K2 deficiency.

Another study showed significant improvement in arterial stiffness in women taking Vitamin K2.

I’m taking an anti-coagulant now. Is it safe to take vitamin K2?

Studies have shown that a low dose (45 micrograms) as MK-7 is unlikely to interfere with blood thinning medication and does not provoke any risk of clot formation inside the blood vessels.

Bone health:

The entire skeleton is replaced every 7 to 10 years through an active process called remodeling. This process involves osteoblasts (cells that build up the skeleton) and osteoclasts (cells that break down the skeleton). As long as absorption exceeds resorption, the process of maintaining bones remain healthy. We typically attained 90% of peak bone mass by age 18 for girls and 20 for boys and by our early 30s we reach our peak bone mass and it simply declines from there.

Osteoblasts produce a protein called osteocalcin. Osteocalcin must be activated (or carboxylated) by vitamin K2 to properly bind calcium to bones. Calcium is essential to maintain bone strength and to inhibit osteoporosis and fracture.

To prevent osteoporosis, we need to maintain a proper weight, weight bearing and resistance exercise and take supplements including calcium, magnesium, zinc, vitamin D and vitamin K2. Children were also shown to have deficiency in vitamin K2 and may need supplements.

Adequate vitamin K2 is virtually non-existent in today’s food supply especially for MK-7.

Research studies have found 180mcg MK-7 per day as a safe and effective dosage for adults.

Magnesium like vitamin K2 has a significant positive effect on bone and cardiovascular health. Mg can reduce the risk of heart disease by 25%.