{"id":24179,"date":"2021-02-17T10:00:00","date_gmt":"2021-02-17T18:00:00","guid":{"rendered":"https:\/\/foodrevolution.org\/?p=24179"},"modified":"2024-11-13T09:20:16","modified_gmt":"2024-11-13T17:20:16","slug":"vitamin-k-benefits","status":"publish","type":"post","link":"https:\/\/foodrevolution.org\/blog\/vitamin-k-benefits\/","title":{"rendered":"Vitamin K: Benefits, How to Get It, and How Much You Need"},"content":{"rendered":"

In 1916, a chemist named Cornelia Kennedy left her job teaching \u201cdomestic science\u201d to female students at the University of Minnesota for a research position at the University of Wisconsin, where her advisor was trying to figure out how to put together healthy animal feeds. In a paper on malnourished pigeons, Kennedy wrote<\/a> of two chemicals, which she called \u201cfat-soluble A and water-soluble B.\u201d And just like that, we had a naming system for these newly-discovered nutrients, which came to be known as vitamins.<\/p>\n

You\u2019re undoubtedly familiar with the first five vitamins to be identified and named: A, B, C, D, and E. But then what happened? The next (and as it turned out, final) alphabetic vitamin is K, seemingly an insignificant afterthought. What happened to F, G, H, I, and J? Did scientists not know the alphabet song? Is vitamin K really not a big deal? This article covers what vitamin K is and does, how much you need, and the best places to get it in your diet.<\/p>\n

What Is Vitamin K?<\/h2>\n
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Vitamin K is a fat-soluble vitamin<\/a>, which means it doesn\u2019t dissolve in water. And excess (unused) amounts in your body are stored in your liver and fatty tissues. The absorption of vitamin K and other fat-soluble vitamins is best optimized when you consume them with some dietary fat.<\/p>\n

Vitamin K is primarily involved<\/a> in blood clotting, bone metabolism, and building proteins. It does its work in your liver and other tissues, including your brain, pancreas, and heart, as well as your skeletal system. Discovered in 1929, it was named<\/a> vitamin K not as part of the alphabet scheme, but because the Danish researcher Henrik Dam found that it prevented chickens on a fat-free diet from bleeding out. He called it the \u201ckoagulation\u201d vitamin (using the German spelling), or vitamin K.<\/p>\n

And why not vitamin F, the next letter in line? It turns out that F, G, and H had been used<\/a> until the chemical compounds they referred to were found not to be actual vitamins: F turned out to be the omega fatty acids; G was discovered to be part of the B vitamin group (B2, to be exact), and H was reclassified as biotin (or B7). So by the time Henrik Dam cured chicken bleed-out with hemp seeds, he was free to choose any letter he wanted.<\/p>\n

Back to our story. Unlike the other fat-soluble vitamins, only very small amounts of vitamin K circulate in your blood at any given time. In fact, if you take a one-time, supplemental dose of vitamin K, your body will keep approximately 30-40% of it to use and store, and get rid of the rest. Your body has a limited amount of storage for vitamin K, so some of it is also recycled and reused<\/a> multiple times.<\/p>\n

Types of Vitamin K<\/h3>\n

While vitamin K sounds like one compound, there are actually two kinds<\/b>. The first is vitamin K1, or phylloquinone, which is primarily found in cauliflower and leafy green veggies<\/a> like spinach, kale, and cabbage. This is the main form of vitamin K found in the diet, yet some studies show most people absorb only about 10%<\/a> of the vitamin K1 they ingest.<\/p>\n

The other type is vitamin K2, or menaquinone, which is predominantly made by human and animal gut bacteria<\/a>. Moderate amounts of K2 are found in certain fermented soy foods<\/a> (especially natto, which is something of an acquired taste) and animal products<\/a> like butter, beef liver, curdled cheese, and egg yolks. Interestingly, your gut bacteria appear to convert some vitamin K1 from your diet into K2, although the extent and efficiency of this conversion varies based on a number of factors.<\/p>\n

Vitamin K Health Benefits<\/h2>\n
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Both vitamin K1 and K2 are important for maintaining your overall health. Below are a few of the best-known health benefits of both forms of vitamin K.<\/p>\n

Helps with Blood Coagulation<\/h3>\n

This may be the most well-known role of vitamin K in your body. Remember, vitamin K was named after the German word \u201ckoagulation.\u201d Both vitamins K1 and K2 are involved in blood clotting<\/a>, which is what keeps you from bleeding to death when you get a cut. Specifically, vitamin K is needed to manage proteins<\/a> involved in the blood clotting process. If you don\u2019t get enough vitamin K, you are more likely to experience hemorrhaging<\/a>, or excessive bleeding, from a wound.<\/p>\n

Good for Your Teeth and Bones<\/h2>\n

Inadequate intake of vitamin K has been linked to an increased risk<\/a> for osteoporosis \u2014 a disease in which the bones become soft and porous \u2014 and bone fractures. Both vitamins K1 and K2 may also help with regulating calcium balance<\/a>, which maintains skeletal strength. Seven trials have found<\/a> that vitamin K2, specifically, reduced spinal fractures by 60%, hip fractures by 77%, and all non-spinal fractures by 81%. High doses of vitamin K2 have also been used to prevent further bone mineral loss and reduce the risk of fractures in patients with osteoporosis<\/a>.<\/p>\n

Vitamin K2-Specific Health Benefits<\/h2>\n

There are also some health benefits that seem to be tied only to vitamin K2.<\/p>\n

May Reduce Your Risk of Heart Disease<\/h3>\n

Vitamin K2 may help prevent calcification<\/a> that results from calcium buildup in your arteries<\/a>. This accumulation is associated with atherosclerosis, a risk factor for heart disease. A 2009 study of 16,057 women found<\/a> that for every 10 mcg of K2 that participants consumed each day, their heart disease risk was reduced by 9%.<\/p>\n

May Support Brain Health<\/h3>\n

Vitamin K2 seems to be involved in processes that help protect your brain as you age. For instance, it plays a role in the production of compounds called sphingolipids, which are highly concentrated in the brain (and which sound like a lot of fun!). Changes in the metabolism of sphingolipids<\/a> have been linked to neurodegenerative diseases like Alzheimer\u2019s. Recent evidence also suggests that vitamin K2 may help protect<\/a> against oxidative stress and inflammation, and may influence psychomotor behavior and brain function.<\/p>\n

May Have Anticancer Benefits<\/h3>\n

A few studies have indicated that vitamin K2 may help reduce the recurrence<\/a> of liver cancer and increase survival. And in a 2008 study<\/a> published in the American Journal of Clinical Nutrition<\/i>, researchers found that men with a high intake of vitamin K2 had a 63% lower risk for advanced prostate cancer.<\/p>\n

How Much Vitamin K Do You Need?<\/h2>\n

Vitamin K is obviously doing some important work in your body, so how much should you be getting? Currently, most health authorities focus on K1<\/a> specifically, which is a shame because it seems that K2 is equally important for long-term health. According to the National Academy of Medicine, the <\/b>daily requirement<\/b><\/a> for vitamin K1 from foods is 90 micrograms (mcg) for women and 120 mcg for men.<\/b> The World Health Organization and the Food and Agriculture Organization make recommendations<\/a> that come out to an average of 55 mcg per day for women and 65 mcg per day for men.<\/p>\n

While the recommended amounts vary, for most people getting enough vitamin K1 is not a problem<\/a>. Most people who eat enough total calories get more<\/a> than the recommended amount of it.<\/p>\n

But K2 seems like it deserves more attention. And a few health authorities have even gone so far as to state a separate recommendation for it. Some scientists studying the effects of K2 suggest that its health benefits are best seen with a daily intake of <\/b>between 10-40 mcg<\/b><\/a>.\u00a0<\/b><\/p>\n

Vitamin K Deficiency<\/h2>\n
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While deficiency of vitamin K1 is rare, it\u2019s possible in the event of severe malnutrition. Those suffering from gastrointestinal disorders, or who have trouble absorbing fat, may be at risk of K1 deficiency. Other at-risk groups include babies who are breastfed by mothers who are vitamin K deficient, and adults who have taken coumarin anticoagulants (the best-known are the blood-thinning medications Coumadin and Warfarin). This is because these drugs can interfere with the synthesis of vitamin-K dependent coagulation proteins in the liver. Members of these groups may need their vitamin K status monitored. And they may require supplementation but should discuss the matter with a qualified healthcare provider first.<\/p>\n

Vitamin K2 deficiency is trickier to diagnose, as the harm is mostly long-term. However, problems with blood clotting \u2014 like excessive bleeding from wounds \u2014 or unexplainable bruising under the skin may be signs of a potential K2 deficiency and should be examined further.<\/p>\n

There may also be a link between vitamin K deficiency and <\/b>osteoporosis<\/b><\/a>.<\/b> Studies have found<\/a> that vitamin K2 prevents osteoporotic fractures and prevents vertebral fractures.<\/p>\n

Vitamin K-Rich Foods<\/h2>\n
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Some of the best vitamin K1-containing foods are<\/strong>:<\/p>\n