The Two Basic Types of Vitamin K – K1 and K2
Vitamin K can be classified as either K1 or K2:
- Vitamin K1: Found in green vegetables, K1 goes directly to your liver and helps you maintain a healthy blood clotting system. This is the kind of K that infants need to help prevent a serious bleeding disorder. It is also vitamin K1 that keeps your own blood vessels from calcifying, and helps your bones retain calcium and develop the right crystalline structure.
- Vitamin K2: Bacteria produce this type of vitamin K. It is present in high quantities in your gut, but unfortunately most is passed out in your stool. K2 goes straight to vessel walls, bones and tissues other than your liver. It is present in fermented foods, particularly cheese and the Japanese food natto, which is by far the richest source of K2.
Vitamin K1 can convert to K2 in your body, but there are some problems with this; the amount of K2 produced by this process alone is typically insufficient. Making matters even more complex, there are several different forms of vitamin K2. MK-8 and MK-9 come primarily from dairy products. MK-4 and MK-7 are the two most significant forms of K2 and act very differently in your body:
MK-4 is a synthetic product, very similar to vitamin K1, and your body is capable of converting K1 into MK-4. However, MK-4 has a very short biological half-life of about one hour, making it a poor candidate as a dietary supplement.
After reaching your intestines, it remains mostly in your liver, where it is useful in synthesizing blood-clotting factors.
- MK-7 is a newer agent with more practical applications because it stays in your body longer; its half-life is three days, meaning you have a much better chance of building up a consistent blood level, compared to MK-4 or K1. MK-7 is extracted from the Japanese fermented soy product called natto.
You could actually get loads of MK-7 from consuming natto, as it is relatively inexpensive and is available in most Asian food markets. Few Americans, however, tolerate its smell and slimy texture.
Vitamin K2 as MK-7 Helps Prevent Inflammation in Your Body
Vitamin K2, particularly menaquinone-7 (MK-7), has been the subject of much research because it stays active in your body longer so you are able to benefit from much lower levels. A study from the Czech Republic evaluated the role of MK-7 in inflammation and found that it prevents inflammation by inhibiting pro-inflammatory markers produced by white blood cells called monocytes.
It's important to realize that dietary components can either trigger or prevent inflammation from taking root in your body. For example, whereas synthetic trans fats and sugar, particularly fructose, will increase inflammation, eating healthy fats such as animal-based omega-3 fats found in krill oil or the essential fatty acid gamma linolenic acid (GLA) will help to reduce it.
MK-7 appears to be one more healthful natural substance that can be added to the anti-inflammatory list, as for inflammation in general, if you have not already addressed your diet, this would be the best place to start, regardless of whether you're experiencing symptoms of chronic inflammation or not.
What Else Is Vitamin K2 Good For?
The health benefits of vitamin K2 go far beyond blood clotting, which is done by vitamin K1, and vitamin K2 also works synergistically with a number of other nutrients, including calcium and vitamin D. Its biological role is to help move calcium into the proper areas in your body, such as your bones and teeth. It also plays a role in removing calcium from areas where it shouldn't be, such as in your arteries and soft tissues.
Researchers are also looking into other health benefits, as well. For example, one study published in the journal Modern Rheumatology found that vitamin K2 has the potential to improve disease activity besides osteoporosis in those with rheumatoid arthritis (RA). Another, published in the journal Science found that vitamin K2 serves as a mitochondrial electron carrier, thereby helping maintain normal adenosine triphosphate (ATP) production in mitochondrial dysfunction, such as that found in Parkinson's disease.4 Further, according to a 2009 Dutch study, subtypes MK-7, MK-8 and MK-9 in particular are associated with reduced vascular calcification even at small dietary intakes (as low as 1 to 2 mcg per day).5
What Are the Best Food Sources of Vitamin K2, Including MK-7?
You can obtain all the K2 you'll need (about 200 micrograms) by eating 15 grams of natto daily, which is half an ounce. However, natto is generally not appealing to a Westerner's palate, so you can also find vitamin K2, including MK-7, in other fermented foods. Fermented vegetables, primarily for supplying beneficial bacteria back into your gut, can be a great source of vitamin K if you ferment your own using the proper starter culture.
We had samples of high-quality fermented organic vegetables made with our specific starter culture tested, and were shocked to discover that not only does a typical serving of about two to three ounces contain about 10 trillion beneficial bacteria, but it also contained 500 mcg of vitamin K2.
Note that not every strain of bacteria makes K2. For example, most yogurts have almost no vitamin K2. Certain types of cheeses are very high in K2, and others are not. It really depends on the specific bacteria. You can't assume that any fermented food will be high in K2, but some fermented foods are very high in K2, such as natto. Others, such as miso and tempeh, are not high in K2. Cheeses highest in K2 are Gouda and Brie, which contain about 75 mcg per ounce. Additionally, scientists have found high levels of MK-7 in Edam Cheese.
How Much Vitamin K2 Do You Need?
Although the exact dosing is yet to be determined, Dr. Cees Vermeer, one of the world's top researchers in the field of vitamin K, recommends between 45 mcg and 185 mcg daily for adults. You must use caution on the higher doses if you take anticoagulants, but if you are generally healthy and not on these types of medications, I suggest 150 mcg daily. Fortunately, you don't need to worry about overdosing on K2—people have been given a thousand-fold "overdose" over the course of three years, showing no adverse reactions (i.e., no increased clotting tendencies). If you have any of the following health conditions, you're likely deficient in vitamin K2 as they are all connected to K2:
- Do you have osteoporosis?
- Do you have heart disease?
- Do you have diabetes?
Please note also that if you opt for oral vitamin D, you also need to consume vitamin K2 in your food or take supplemental vitamin K2, as they work synergistically together and an imbalance may actually be harmful. If you do not have any of those health conditions, but do NOT regularly eat high amounts of the following foods, then your likelihood of being vitamin K2 deficient is still very high:
- Grass-fed organic animal products (i.e. eggs, butter, dairy)
- Certain fermented foods such as natto, or vegetables fermented using a starter culture of vitamin K2-producing bacteria
- Certain cheeses such as Brie and Gouda (as mentioned, these two are particularly high in K2, containing about 75 mcg per ounce)
If You're Considering a Vitamin K2 Supplement…
There's no way to test for vitamin K2 deficiency. But by assessing your diet and lifestyle as mentioned above you can get an idea of whether or not you may be lacking in this critical nutrient. The next best thing to dietary vitamin K2 is a vitamin K2 supplement. MK-7 is the form you'll want to look for in supplements, because in a supplement form the MK-4 products are actually synthetic. They are not derived from natural food products containing MK-4. The MK-7– long-chain, natural bacterial-derived vitamin K2– is from a fermentation process, which offers a number of health advantages:
- It stays in your body longer
- It has a longer half-life, which means you can just take it once a day in very convenient dosing
Finally, remember to always take your vitamin K supplement with fat since it is fat-soluble and won't be absorbed without it.
Vitamin D: A Brief Review
Vitamin D is a key player in your overall health. The name is misleading -- it isn't actually a vitamin at all but a potent neuroregulatory steroidal hormone that influences nearly 3,000 of your 25,000 genes.1
It literally turns on and off genes that can exacerbate -- or prevent -- many diseases. Vitamin D has been shown to influence dozens of conditions.
One of the key factors explaining today's high rates of chronic disease, besides poor diet and sedentary lifestyle, is an epidemic of vitamin D deficiency. It is estimated that 85 percent of Americans have insufficient levels of vitamin D.
Sadly, when the Institute of Medicine's (IOM) Food and Nutrition Board (FNB) released their updated recommendations for vitamin D2 (and calcium) on November 30, 2010, it caused shockwaves of disappointment through the natural health community.
According to the IOM, the new recommended daily allowance (RDA)3 for pregnant women and adults up to 70 years of age is the same as that for infants and children -- a measly 600 IUs. This despite the overwhelming evidence showing that vitamin D is extremely important for a wide variety of health conditions besides bone health, and that most people need about ten times this amount or more.
The best ways to increase your vitamin D levels, in my order of preference, are by:
- Exposing your skin natural sunlight. Vitamin D from sunlight acts as a pro-hormone, rapidly converting in your skin into 25-hydroxyvitamin D, or vitamin D3.
- Taking an oral vitamin D3 supplement whenever natural sun exposure is not an option.
- Now, how do vitamin D and vitamin K play together?
Vitamins D and K: 'The Gatekeeper and the Traffic Cop'
One of the undisputed benefits vitamin D provides for you is improved bone development by helping you ABSORB calcium. This is not news -- we have known about vitamin D and the absorption of calcium for many decades.
But there is new evidence that it is the vitamin K (specifically, vitamin K2) that directs the calcium to your skeleton, while preventing it from being deposited where you don't want it -- i.e., your organs, joint spaces, and arteries. A large part of arterial plaque consists of calcium deposits (atherosclerosis), hence the term "hardening of the arteries.
"Vitamin K2 activates a protein hormone called osteocalcin, produced by osteoblasts, which is needed to bind calcium into the matrix of your bone. Osteocalcin also appears to help prevent calcium from depositing into your arteries.
You can think of vitamin D as the gatekeeper, controlling who gets in, and vitamin K as the traffic cop, directing the traffic to where it needs to go.
Lots of traffic -- but no traffic cop -- means clogging, crowding, and chaos everywhere!
In other words, without the help of vitamin K2, the calcium that your vitamin D so effectively lets in might be working AGAINST you -- by building up your coronary arteries rather than your bones.
There is even evidence that the safety of vitamin D is dependent on vitamin K, and that vitamin D toxicity (although very rare with the D3 form) is actually caused by vitamin K2 deficiency.5
Vitamin K, Vitamin D, and Cardiovascular Disease
When your body's soft tissues are damaged, they respond with an inflammatory process that can result in the deposition of calcium into the damaged tissue. When this occurs in your blood vessels, you have the underlying mechanism of coronary artery disease -- the buildup of plaque -- that can lead you down the path to a heart attack.
Vitamin K and vitamin D work together to increase Matrix GLA Protein (or MGP), the protein responsible for protecting your blood vessels from calcification. In healthy arteries, MGP congregates around the elastic fibers of your tunica media (arterial lining), guarding them against calcium crystal formation.
MGP is so important that it can be used as a laboratory measure of your vascular and cardiac status.
As you would predict, scientific studies confirm that increased dietary intake of vitamin K2 does indeed reduce your risk for coronary heart disease:7
- In 2004, the Rotterdam study was the first study demonstrating the life-extending effects of vitamin K2. People who had the highest intake of vitamin K2 had 50 percent lower risk of death from coronary heart disease and calcification than people with the lowest intake of vitamin K2.
- In a subsequent study called the Prospect study, 16,000 people were followed for 10 years. Researchers found that each additional 10 mcg of vitamin K2 in the diet resulted in nine percent fewer cardiac events.
- Animal studies show that vitamin K2 not only prevents hardening of the arteries but can actually reverse calcification of highly calcified arteries by activating MGP.
- People with severe calcifications have high percentages of inactive osteocalcin, which indicates a general deficiency of vitamin K2.
Let's take a look at how calcium supplements play into all of this.
Does Your Calcium Supplement Actually Increase Your Risk of Heart Attack?
If you take calcium and vitamin D but are deficient in vitamin K, you could be worse off than if you were not taking those supplements at all, as demonstrated by a recent meta-analysis8 linking calcium supplements to heart attacks.
This study did indeed find that people taking calcium supplements were more prone to heart attacks. However, that doesn't mean that it was the calcium supplements themselves that caused the heart attacks.
Please remember that calcium is only ONE of the players in your bone and heart health.
This meta-analysis looked at studies involving people taking calcium in isolation, without complementary nutrients like magnesium, vitamin D, and vitamin K, which help keep your body in balance. In the absence of those other important cofactors, calcium CAN have adverse effects, such as building up in coronary arteries and causing heart attacks, which is really what this analysis detected.
And the FORM of calcium you take matters greatly, which I will address in a moment.
You simply can't take isolated supplements "willy-nilly" and expect to optimize very complicated physiological processes.
Vitamin D itself has been found to protect your heart. A study in the Netherlands provides compelling evidence that a high vitamin D status is associated with improved survival in heart failure patients.
If you are going to take calcium, you need to balance it out with vitamin D and vitamin K, at the very least. It is also important that you get adequate magnesium, silica, omega-3 fatty acids, and weight-bearing exercise, which are all important to the health of your bones.
Which leads us to the next important topic: osteoporosis.
Dense Bones Are NOT Necessarily Strong Bones
One of the great health concerns for menopausal women is osteoporosis.
The classic way osteopenia (decreased bone density) and osteoporosis are diagnosed is by an x-ray called a DEXA scan, which specifically measures bone density, or the degree of mineralization of your bones.
But bone strength is MORE than bone density -- which is why drugs, such as biphosphinates, have failed so miserably.
Your bones are made up of minerals in a collagen matrix.9 The minerals give your bones rigidity and density, but the collagen gives your bones flexibility. Without good flexibility, they become brittle and break easily.
So, density does NOT equal strength!
Some pharma Drugs build up a lot of minerals and make the bone LOOK very dense, but in reality, they are extremely brittle and prone to fracture, which is why there have been so many cases of hip fracture among people taking these damaging drugs.
Biphosphinates are poisons that destroy your osteoclasts. These drugs interfere with your normal bone-remodeling process.
You are much better off building your bones using exercise and nutritional therapies, hormones like progesterone and vitamins D and K.
The Calcium Myth: Revising Our Theory of Bone Mineralization
Countries with the highest calcium consumption have the highest rates of osteoporosis -- namely, the U.S., Canada and Scandinavian countries. This is commonly known as the "calcium paradox."
This is because nutritional guidelines have been based on an incorrect theory of bone mineralization
When you take the wrong form of calcium, or when your body's ability to direct calcium to the right places becomes impaired (as when you are deficient in vitamin K), calcium is deposited where it shouldn't be -- like sand in gears.