Just as there has been an explosion of positive science about the importance of vitamin D3, another nutrient, vitamin K, is showing tremendous promise in the treatment and prevention of a wide range of health conditions. Since most people are not getting anywhere near a sufficient level of vitamin K in their diet, it is one nutrient that you simply need to learn more about.
Supplementing with vitamin K
The importance of vitamin K supplementation has been known for a long time. Since 1961, a vitamin K1 injection has been given to all newborn babies to prevent hemorrhagic disease, and to help establish gut microflora.
It now appears that it is not just newborns that can benefit from vitamin K supplementation; new clinical data shows tremendous benefits in its use for the prevention and treatment of osteoporosis, rheumatoid arthritis and heart disease.
A primer on vitamin K
Vitamin K is a fat-soluble vitamin that is most famous for its role is in the manufacture of clotting factors. However, recent studies have shown that vitamin K is also necessary for building healthy bones and may play a role in treating and preventing osteoporosis.
There are several forms of vitamin K, designated as K1, K2 and K3. The first form, K1 (or phylloquinone) is derived from plant sources. K2 (menaquinone) is produced by bacteria and found in some fermented foods. There are several different forms of K2, but MK-7 is the most important commercial form of vitamin K2. K3 is a synthetic form.
Vitamin K is often overlooked as a vitamin, since deficiency is thought to be quite rare; there are good dietary sources of K1, and gut bacteria can produce K2. Rich sources of vitamin K1 are dark green leafy vegetables, broccoli, lettuce, cabbage, spinach and green tea, as well as asparagus, oats, whole wheat and fresh green peas. MK-7 is found in especially high concentrations in natto, a fermented soy food popular in Japan; a three-ounce serving of natto provides 850 mcg of MK7.
Vitamin K in osteoporosis
Vitamin K plays an important role in bone health as it is responsible for converting the bone protein osteocalcin from its inactive form to its active form. Osteocalcin is the major non-collagen protein found in our bones that anchors calcium into place within the bone. That may be why low intake of vitamin K1 is linked to osteoporosis and hip fractures. Since vitamin K1 is found in green leafy vegetables, it may also be one of the protective factors of a vegetarian diet against osteoporosis.
But MK-7 has been found to be more potent and more bioavailable and is also more effective than K1 in activating osteocalcin. It also stays in the blood circulation much longer. In a landmark major clinical published in the March 23, 2013 issue of Osteoporosis International, MK-7 supplementation at relatively low dosage levels (180 mcg per day) produced tremendous effects in improving bone health. These results highlight the importance of MK-7 supplementation in post-menopausal women.
MK-7 in rheumatoid arthritis
Rheumatoid arthritis (RA) is a chronic inflammatory condition that affects the entire body, especially the joints. RA is a classic example of a multi-factorial disease, wherein an assortment of genetic, dietary and environmental factors contribute to its onset.
Based on pre-clinical studies showing that another form of vitamin K2 (MK-4) blocked the development of arthritis in the experimental animal model of RA, it was suggested that MK-4 might offer benefits in human RA. And since MK-7 has greater bioavailability than MK-4 after oral administration, researchers were quite curious if even better results might be produced with this form.
To assess the benefits of MK-7, the clinical and biochemical markers on RA patients treated with MK-7 and the control group were assessed before and after three months. MK-7 increased the level of the active form of osteocalcin, an important marker of bone health. The benefits were directly related to increased levels of MK-7 in the blood.
Final comment from Dr. Murray
Just as the popularity of vitamin D3 supplementation increased after so many positive scientific investigations, there is now a similar phenomenon occurring with vitamin K, specifically MK-7. That’s why it’s important for us to understand the different forms of vitamin K and the effective dosage ranges used in clinical studies. See below:
- For osteoporosis, the general recommendation is 180 mcg of MK-7 per day.
- For RA, the dosage used in the clinical trial was 100 mcg of MK-7 per day.
- For general health, most experts recommend an intake of 80-120 mcg of vitamin K1 or K2.
Obviously, in patients on anticoagulant therapy with warfarin (Coumadin), vitamin K supplementation is not advised. Otherwise there are no other known issues with taking vitamin K1 or MK-7 at recommended dosage levels.