I have previously written on the different forms of vitamin K, and the importance of K2 in preventing two of the most widespread ailments in the modern world, namely atherosclerosis and osteoporosis. In that blog we saw how K2 keeps calcium out of the arteries, forbidding hardening of the arteries, and channels it back into the bones, and teeth, helping to keep the skeletal structure strong. In this article I will look at some of the other most important functions of K2 in the body and how it can prevent a number of other serious diseases. (Importance of vitamin K2.)
NEW DISCOVERIES ABOUT VITAMIN K2
Some of the highest concentration of vitamin K2 in the body, are located in the salivary glands and the pancreas, with these organs showing a definite preference for vitamin K2 over K1 (found in leafy green vegetables). The high amounts of vitamin K2 found in the pancreas clearly is related to regulating blood sugar, as we will see below. The presence of large amounts of K2 in the salivary glands is explained by its value in preventing, and possibly even reversing, dental carries, another area that I will examine.
The ongoing research into the properties of vitamin K2 indicate that more areas of interest are to be discovered in the future, two of which I won’t have space to go into but are nonetheless quite intriguing. One is the preferential retention of vitamin K2 found in the testes of male rats, which, when considered in conjunction with the fact that human sperm contains a protein that is vitamin K dependent, implies that it is necessary for healthy fertility.
Another recent finding is that the kidneys store large amounts of vitamin K2, and also secrete a protein component dependent on K2, one that prevents the formation of calcium salts. We know that people who have kidney stones only secrete this protein in an inactive form that poorly inhibits the development of kidney stones, suggesting that K2 may be an important piece of the puzzle of why some people develop kidney stones more than others do. (Vermeer C, Soute BAM, Ulrich MMW, van de Loo PGF. Vitamin K and the Urogenital Tract. Haemostasis. 1986; 16: 246-257.)
VITAMIN K2 AND VITAMIN D3
Science has long known that vitamin D is essential for the absorption of calcium, but now we know that it is the vitamin K2 that directs the calcium into the skeleton, while preventing it from being deposited in the organs, joints and arteries.
There is now evidence that the safety of vitamin D3 is dependent on vitamin K2, and that vitamin D toxicity may be caused by vitamin K2 deficiency. So, the vitamin D3 mobilizes calcium into the bloodstream, but if the K2 is not present to channel the calcium into the bones, it can just build up on plaque on the arterial walls, leading to atherosclerosis.
Vitamin K2 and vitamin D3 work together to increase what is known as Matrix GLA Protein (or MGP), the protein responsible for protecting your blood vessels from calcification, preventing hardening of the arteries. MGP status is so important that it can be used as a laboratory measure of your vascular and cardiac status, if you have a doctor advanced enough to give you such a test.
Since the body stores most of the vitamin D that it would obtain from sunshine, in an inactive form, converting it into an active form as required, we should be careful with supplements of vitamin D, as they are all in the active form of D3. In other words, we are ingesting an “end product” instead of a precursor, or building block that allows the body to produce as much of the end product as it optimally requires.
Therefore, those of us taking anything more than 3,000IU to 5,000IU of vitamin D3 daily, should definitely add a vitamin K2 supplement to the regimen, for that reason alone.
VITAMIN K2 AND STROKE
The importance of vitamin K2 in preventing osteoporosis may indicate another valuable function that it performs as well. In a “Study of Osteoporotic Fractures” it was shown that bone density is a good general predictor of early mortality. This study found that every standard deviation from normal bone density lead to a 20% greater risk of mortality in older women. An update to this study further confirmed the findings of the original study, concluding that there was a 1.23 greater risk of dying if a subject had one or more back fractures. Severe osteoporosis increased the risk of dying from a lung-related disorder by 2.6 times. (Browner WS, et al. 1991. Non-trauma mortality in elderly women with low bone mineral density. Study of Osteoporotic Fractures Research Group. Lancet 338:355-58.)
What was discovered was that the women with osteoporosis didn’t die from complications from broken bones or the resulting surgery; falling accounted for only about 3% of the mortalities in this study. The majority of deaths actually occurred mostly from cancer, heart attack and stroke. Science now suspects that osteoporosis is a warning sign that calcium has built up in the arteries, instead of remaining in the bones, where it belongs.
The underlying cause of stroke is pretty much the same as the cause of a heart attack: damaged blood vessels. Up until recently, it was believed that a high sodium diet caused hypertension and strokes but recently the JAMA came to the conclusion that “These results do not support a general recommendation to reduce sodium intake.” (The Truth About Salt blog.)
More recent studies have shown that another mineral that affects blood pressure, calcium, may be more likely to negatively affect blood pressure than sodium. (Killing with Calcium blog.) The repeated link between high calcium intake (1200 – 1500mg supplemental) and stroke and heart disease, supports the concept that calcium build up in the arteries is logically linked to causing strokes.
In the aforementioned “Study of Osteoporotic Fractures”, one standard deviation from the norm of bone density was equal to a three times increased risk of having a stroke and a 1.7 times increased risk for hypertension. And for further support of this theory, it has been shown that diets high in vitamin K prevent the thickening of arteries in rats prone to stroke.
INFLAMMATION AND VITAMIN K2
It well known that inflammation is the root of many ailments including cancer, heart disease, diabetes and arthritis. The older we get the more we produce the inflammatory compound called Interleukin-6, a chemical messenger known as a cytokine that is part of our immune system. When produced in normal amounts it is a necessary component of a healthy immune system, but when it overwhelms the other cytokines, IL-6 causes excessive inflammation.
This is confirmed by findings from the National Research Institute in Italy, that show IL-6 to be concentrated in damaged blood vessels and joints showing arthritic conditions. Their study showed that people with the highest amount of IL-6 were nearly twice as likely to develop mobility-related ailments. Elevated levels of IL-6 were also found in people with symptoms of Alzheimer’s disease, also a disease characterized by symptoms of inflammation. (Ferrucci L, et al. 1999. Serum IL-6 level and the development of disability in older persons. J Am Geriatr Soc 47:639-46.) Fortunately vitamin K2 also inhibits both IL-6 and general inflammation.
ALZHEIMER’S DISEASE AND VITAMIN K2
Some years ago a research scientist at the University of North Carolina discovered that hemodialysis patients were more prone to bone fractures, and at the same time had higher than normal levels of a compound called “apolipoprotein E” in their blood. The scientist (Dr. M. Kohlmeier) suspected that these people might also be prone to poor vitamin K status or may not absorb or produce it well, and eventually studies confirmed this fact. Later, elevated levels of this apoE compound were directly linked to Alzheimer’s disease. The combination of low vitamin K and high apoE affected the body’s ability to regulate calcium levels in the brain. And, indeed, studies have found that patients with Alzheimer’s disease have unhealthy calcium levels in their brains. (Knapen MHK, et al. 1989. The effect of vitamin K supplementation on circulating osteocalcin (bone Gla protein) and urinary calcium excretion. Ann Internal Med 111:1001-5.)
VITAMIN K2 AND INSULIN REGULATION
The fact that some of the highest levels of vitamin K are stored in the pancreas has lead to the idea that it may also be a necessary part of controlling blood sugar levels. Japanese scientists did study the link between vitamin K and insulin function in the body and, while it was an animal study, what occurred with vitamin K deficiency mimicked what occurs with diabetics. That is that the deficiency in vitamin K interferes with the clearance of glucose from the blood and then stimulates an excessive insulin release. (Sakamoto N, et al. 1999. Low vitamin K intake effects on glucose tolerance in rats. Int J Vit Nutr Res 69:27-31)
A small scale human study, done in 2011, concluded: “To summarize, we have demonstrated for the first time that vitamin K2 supplementation for 4 weeks increased insulin sensitivity in healthy young men.” (Hyung Jin Choi, MD, et al; “Vitamin K2 Supplementation Improves Insulin Sensitivity via Osteocalcin Metabolism: A Placebo-Controlled Trial”; Diabetes Care September 2011 vol. 34 no. 9 e147)
Considering that insulin malfunction is linked not only to diabetes, which is bad enough, but also to the risk of developing certain types of cancer and to Alzheimer’s disease, the importance of taking in adequate amounts of vitamin K2 becomes even more obvious. More on the further benefits of vitamin K2 in the next blog.