Vitamin K2 - Menaquinone
Menaquinone, or vitamin K-2, plays a bigger role in bone and artery health than most people realize.
Vitamin K, much like vitamin E, is a collective term for a large group of many different related molecules or subtypes.
Vitamin K is a fat-soluble vitamin occurring in two main biologically active forms: K1 (phylloquinone, vegetarian form) and K2 (menaquinone, animal form).
Vitamin K helps regulate calcium balance, or puts the calcium from supplements where people want it to go (i.e.,, in their bones and teeth rather than in soft tissue or arterial calcification).
Supplementing with excess amounts of calcium, without simultaneously getting adequate amounts of vitamin K-2, menaquinone, in your nutrition is harmful. Remember our call for moderation, where less is often more. The unfortunate result of this calcium paradox is death from atherosclerosis or hardening of the arteries.
K-2 and the Calcium Paradox
Prevent Atherosclerosis & Osteoporosis with K-2
Vitamin K-2 solves the final piece of the osteoporosis, or bone loss, prevention puzzle. Furthermore, adequate supplementation with vitamin K-2 can simultaneously prevent atherosclerosis, arterial calcification, plaque buildup in arteries, or hardening of the arteries.
The result of the long-term development of plaque buildup are heart attacks and strokes.
Dietary Sources for Vitamin K-2
First, including leafy green vegetables (i.e., "greens") in your diet will result in good K-1 (phylloquinone) nutrition. Some soft tissues in your body have a remarkable capacity to convert up to 90% of the available K1 into K-2, or more precisely Menaquinone-4 (MK4). Nevertheless, be warned, that taking prescription antibiotics can reduce vitamin K-1 production in the gut, the seat of your immune system, by nearly three-quarters.
The number one direct food source of K-2 is fermented Japanese soybean Natto. However, being able to stomach Natto is an acquired taste. Next, in menaquinone content would come from consuming homemade fermented vegetables that were made from a starter culture of vitamin K2-producing bacteria (i.e., Bacillus subtilis). Adequate dairy sources would include Brie and Gouda cheese. It is more important that cheese food sources were produced from the correct bacteria starter cultures, than from free-ranged cows. Finally, consume food products made from grass grazed farm animals, such as egg yolks, butter, and other dairy products.
Of course, organic health food sources of K-2 should be preferred, since they will provide the additional health benefit of containing live K-2 producing bacteria.
Supplementing with Vitamin K-2 gets complicated.
Vitamin K2 (menaquinone) includes two main subtypes: menaquinone-4 (MK4) and menaquinone-7 (MK7). Menaquinone-4 is synthesized by animals. While menaquinone-7 is synthesized only by bacteria during fermentation.
In conclusion: the position of the Natural Health Perspective is that everyone should be supplementing daily with 200 mcg of vitamin K-2. There are no known toxic levels for the oil-soluble Vitamin K-2. Thus, there should be little concern over including even more in your nutrition. Supplementation, will immediately correct any vitamin K-2 insufficiency problems while you are working on improving your diet.
Undifferentiated vitamin K-2 supplement products will contain a mixture of different menaquinones, which is usually mostly menaquinone-4. These MK4 supplements work great to prevent bone loss, but NOT as well in preventing hardening of your arteries, as supplementing with our suggested menaquinone-7 supplement would. MK7 supplements cost more, but are reported to hang around longer in your body.
Maintaining strong bones throughout your lifetime requires avoiding nutritional insufficiencies of both vitamins D-3 and K-2 and the minerals calcium and magnesium in your nutrition; along with adequate amounts of load bearing exercise.
Please read our Nutritional Supplements Disclaimer.
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