The Importance of Vitamin K2

Vitamin K is an essential vitamin that is important for blood clotting, strong bones and heart health. One of vitamin K’s most important roles is to regulate calcium deposition. This process calcifies bones, or in other words, strengthens them. Vitamin K2 also helps prevent calcification of blood vessels which can lead to heart disease. Vitamin K occurs in 2 main forms: vitamin K1 and vitamin K2. Most people have never heard of vitamin K2. Vitamin K2 is relatively rare in the Western diet, but it may play an important role in our health.

Vitamins K1 and K2 have different roles, and some scientists even think they should be classified as different nutrients. One study showed that vitamin K2 reduced blood vessel calcification while vitamin K1 did not, while other studies showed that vitamin K2 supplements improved bone and heart health, but vitamin K1 did not. More research is needed to fully understand the functional differences between vitamins K1 and K2.

Vitamin K2 has several subtypes called menaquinones (MKs) which are numbered MK-4 through MK-13, based on the length of their side chains. While the body stores vitamin K1 in the liver, heart and pancreas, vitamin K2 is found in high concentrations in the brain and kidneys. In this article, we will delve into the possible health links of vitamin K2 and how you can increase your vitamin K2 consumption.

Vitamin K2 Health Links:

  1. Blood Clotting:
    The body requires both vitamin K1 and K2 to produce a protein called prothrombin, which is essential for blood clotting, bone metabolism and heart health. Vitamin K1 is known mainly for its blood clotting properties, while vitamin K2 is being looked at for its role in bone and heart health.
  2. Heart Health:
    Vitamin K2 is thought to help prevent calcium build-up in the arteries. Build-up of plaque in the arteries increases the risk of heart disease, including heart attacks and strokes. In one study, individuals with the highest levels of vitamin K2 intake were 52% less likely to have calcification in their arteries and had a 57% lower risk of death from heart disease. In another study of women, those with the highest intake of vitamin K2 were at a lower risk for heart disease. Interestingly, vitamin K1 had no impact in either of these studies. However, these studies are correlational and therefore can not infer cause and effect. Although more research is needed, there is a strong suggestion that vitamin K2 is important for heart health.
  3. Bone Health:
    Vitamin K2 has been looked at for its role in improving bone health. Osteoporosis means porous bones and is very common in Western countries, especially in older women. Osteoporosis increases the risk of bone fractures and breaks, which is especially of concern as we age and are more prone to falls. Calcium is the main mineral found in bones. Vitamin K2 activates the calcium-binding actions of two proteins that help build and maintain bones. One study showed that postmenopausal women taking vitamin K2 supplements had a slower decrease in bone mineral density. Other studies have shown that spinal fractures and hip fractures decreased with vitamin K2 consumption.
  4. Cancer:
    Studies have suggested that vitamin K2 reduces the recurrence of liver cancer and may even increase survival time. One study also showed that a high vitamin K2 intake was associated with a lower risk of advanced prostate cancer. Vitamin K2 has antioxidant properties, which means it can help protect cells against damage from free radicals in the body. Free radicals can lead to cancer. Findings have also suggested that vitamin K2 may suppress the processes that lead to tumor growth. Again, more research is needed to determine a causal link between vitamin K2 and cancer-related health outcomes.
  5. Anxiety and Depression:
    Vitamin K2 has been linked with reduced symptoms of anxiety and depression in rats. High blood glucose levels may increase the risk of anxiety and depression. In the rat study, treatment with vitamin K normalized blood glucose levels and in turn reduced anxiety and depression.

Vitamin K2 Deficiencies:

Vitamin K deficiency is uncommon, but some of us are at higher risk than others. Those at higher risk include individuals with diseases that affect absorption in the digestive tract such as Chron’s or Celiac disease. Some medications can also interfere with vitamin K absorption, which would increase one’s risk for deficiency. Individuals that are severely malnourished and those who drink heavily are also at higher risk for vitamin K deficiency.

How to Get Vitamin K2:

Vitamin K1 is widely available in food, but vitamin K2 is harder to come by. While vitamin K1 deficiencies are very rare, vitamin K2 deficiencies are prevalent. Your body can partially convert vitamin K1 to K2, but evidence suggests that this conversion is not efficient. Therefore, consuming vitamin K2 directly is best. Your gut bacteria can also produce small quantities of vitamin K2. Rich sources of vitamin K2 include high-fat dairy products from grass-fed cows, beef, pork, chicken, fatty fish, egg yolks, liver and other organ meats. Vitamin K is fat-soluble, which means that low-fat and lean animal products do not have much vitamin K. Fermented foods such as sauerkraut, natto and miso also contain vitamin K2. Considering that vitamin K2 is found only in select foods, and that these foods are relatively rare in the Western diet, supplementing with vitamin K2 may be a valid alternative. Many multivitamins will contain both vitamin K1 and K2. You may also purchase vitamin K2 alone or in combination with other nutrients. Supplementing with vitamin K2 can be enhanced by combining it with vitamin D, as the two have synergistic effects. As of now, there is no specific recommended daily intake of vitamin K2. Always speak with your doctor before taking a dietary supplement, as vitamin K can interact with medications such as blood thinners.

Like much of nutritional research, studies into vitamin K2 have shown potential health links, but more research is needed to determine vitamin K2’s specific role in our health. Your best bet is to make sure you are eating a well-balanced diet rich in a variety of whole foods and maintaining a regular exercise routine.


Resources:
  • https://www.healthline.com/nutrition/vitamin-k2
  • https://pubmed.ncbi.nlm.nih.gov/15514282/
  • https://basecamp.com/3052267/projects/16476167
  • https://link.springer.com/article/10.1007/s00198-013-2325-6
  • https://pubmed.ncbi.nlm.nih.gov/16801507/
  • https://www.medicalnewstoday.com/articles/325059
  • https://content.sciendo.com/view/journals/folmed/58/4/article-p264.xml
  • https://www.todaysdietitian.com/newarchives/060113p54.shtml
  • https://www.webmd.com/vitamins-and-supplements/supplement-guide-vitamin-k#1