With the resurgence of research surrounding nutrition and fitness, it’s no wonder our approaches to energy consumption and expenditure have significantly advanced. But in the world of tracking macros and meal prepping, some pretty important dietary components still remain ignored. Two words: vitamins and minerals.
Though not as precise as macronutrient tracking, establishing a rough estimate of your micronutrients, like vitamin and mineral intake, can provide a better sense of where you may be lacking. The best way to track them? Get to know your food sources.
For vitamin K, the food sources are numerous, varied, and delicious. But not all vitamin K is the same.
Vitamin K is a fat-soluble vitamin that can be stored in the body’s liver and fatty tissues. Because the vitamin dissolves in fats, it can only be properly absorbed when paired with one.
That means if you’re going to eat vitamin-K rich foods, you should pay attention to what you’re eating with them. Try olive oil, avocado, nuts, cheeses or other natural fats to ensure optimal intake of your vitamin K.
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Vitamin K is blood-curdling. Luckily, not in the horror genre way but in the necessary-for-blood-clotting way. When Henrik Dam discovered vitamin K, he fittingly named it “Koagulations vitamin,” which is where we get the K.
Vitamin K goes through its own cycle in the body. During this metabolic process, the vitamin undergoes chemical changes to become a cofactor for enzymes required to award proteins the elite title of Gla. Gla proteins are non-negotiable for blood-clotting, bone metabolism, and optimal heart health.
The matrix Gla protein (MGP) inhibits the calcification of your arteries and cartilage by regulating calcium deposition. It’s kind of like sending a special agent to collect the calcium ions in your bloodstream. Reduced coronary calcification through higher vitamin K intake may reduce the risk of coronary heart disease.2
You know the old saying—you need calcium for strong bones.
But calcium can’t get to work as the mineral building block until you offer up vitamin K. Vitamin K regulates the osteocalcin protein so that it can bind with calcium and maintain your bone mineral density (BMD). No vitamin K, no binding.3 Because of this bone bolstering, higher dietary K intake has been shown to decrease fracture risk4 and reduce the rate of bone loss.5
Strong bones? Check. Strong heart? Check.
Strong brain? Check it out; vitamin K modulates the metabolism of major cell membrane components found in high concentrations in your central and peripheral nervous system.
Known as sphingolipids, these compounds are major players in cellular events, like proliferation, differentiation, and cell-to-cell interaction.6 Vitamin K’s role in this lipid modulation relies on its relationship to two proteins: Protein S, lauded for its neuronal protection and Gas6, active in cell growth and survival.7
As you get familiar with your vitamin K food sources, there’s one more thing to bear in mind: there are two different kinds of vitamin K. You need both.
Vitamin K1 is also known as phylloquinone. On your typical list of foods high in vitamin K, K1 is the star. You need a minimum of 50mcg of K1 every day, with higher doses of 120mcg recommended.
Vitamin K2, or menaquinone, is recommended at slightly higher doses. Daily, you should aim to get at least 100mcg. The catch? Vitamin K2 is found in fewer food sources. Often, these sources are not friendly for specialized diets, as K2 is most abundant in fermented food sources and animal products, such as eggs and cheeses.
You may be surprised how many common foods contain a decent amount of vitamin K. Keep in mind that this is not a comprehensive list; the following sources are merely some of the densest K contenders.8,9
Dark green leafy vegetables are essential for a well-rounded diet. In terms of fiber and nutrient content, these veggies top the charts. Luckily, vitamin K1 is found at its highest doses in each green leaf, with the following amounts reported in single cup servings:
Other green vegetables (and herbs) also top the charts with their vitamin K content in one cup servings:
If you’re looking for more satiating sources of vitamin K, legumes may be your best bet. Full of fiber, fats, and protein, these beans and peas can keep you full (of vitamin K) for hours. In a 100 gram serving, they boast the following amounts of vitamin K1:
Between meals of chicken liver, fava beans, and kale, you’ll probably need a snack. Try reaching for a crunchy K contender, like nuts. In addition to being a great source of healthy fats, nuts are a great vitamin K1 food to add to your repertoire. Here’s how much K1 some nuts boast in a single ounce:
Looking for a sweeter K1 source? Let’s not forget what fruits can bring in a single cup:
The highest natural food source of vitamin K2 is just another version of a food from our K1 list: soybeans. However, the preparation changes how much vitamin K these beans can provide.
Natto is a fermented soybean dish from Japan with a taste most often described as acquired. Natto’s K2 content tops out every list at 850mcg in a three ounce serving.
Offal may not be your top food choice, but it does top the vitamin K2 food lists. Here’s the vitamin K2 content of 100 grams of each of the following meats:
If you find offal to be, well, awful, other animal products are high in vitamin K2. Here’s the rundown of other creamy sources in 100 gram servings:
If you’ll recall your daily intake targets (50mcg of K1 and 100mcg of K2), you’ll see that a simple three-egg spinach and cheddar omelette will provide more than enough of each. A hefty scoop of cilantro-laden guacamole and a spoonful of goose liver pate at that potluck will also get the job done.
Despite its abundance in popular food sources and endless pairing combinations, vitamin K deficiency is still a prevailing issue for many.
When vitamin K deficiency becomes serious, the symptoms are equally troublesome: excessive bleeding, bruising, blood clotting under nails, and even dark blood-containing stool.
If any of these sound familiar, you may want to ask your doctor about performing a prothrombin test (PT). In this test, a healthcare professional draws a small amount of blood and adds a chemical to induce clotting. If the clotting takes longer than the usual 11 to 13.5 seconds, you may be deficient.
There are several factors that can contribute to vitamin K deficiency. We’ll start with the fact that American adults are consuming less vitamin K1 and K2 than the recommended daily intake set by the US Food and Drug Administration.10 But even if you’re getting plenty from your diet, you may have malabsorption syndrome as a result of another condition, such as cystic fibrosis or trauma-induced damage.11
Whatever the case, adequate K1 and K2 intake should not be overlooked. Willing to eat your leafy greens but not fermented soybeans? No worries—you can always cover all your vitamin K bases by taking a supplement, like Kado. Kado is HVMN’s daily Omega-3 nootropic stack boasting vitamin K1 and K2 alongside vitamin D for optimal bone and cardiovascular health.12,13 While Kado’s vital vitamins work on strengthening your body, the astaxanthin will strengthen your mind with stress-free focus to get everything done. And then some.
Remember that you need at least 50mcg of K1 and 100mcg of K2. Vitamin K is a fat-soluble vitamin, so you’ll want to take the dietary supplement at mealtimes containing a fat source, like olive oil or some cheese (for an extra boost of K2).
If you’re on any antihemorrhagic medications (blood thinners), such as Coumadin, you should not combine them with a vitamin K supplement unless otherwise instructed by your healthcare provider.
Vitamin K is essential for blood-clotting, bone, and cardiovascular health. Both K1 and K2 are required for optimal body and brain health. While K1 is primarily found in leafy greens, K2 has a home in meat and animal products.
Vitamin K supplements such as Kado are a great way to ensure you’re getting the proper amount of both types. Knocking your daily requirement out in a single swallow always frees up your micronutrient-tracking time to enjoy other activities made better by vitamin K’s robust mind and body benefits.
Now that you know where to find vitamin K, you're ready to enjoy our comprehensive guide about its full body (and mind) benefits.
|1.||Newman P., Shearer M.J. (1998) Vitamin K Metabolism. In: Quinn P.J., Kagan V.E. (eds) Fat-Soluble Vitamins. Subcellular Biochemistry, vol 30. Springer, Boston, MA|
|2.||Gast GC, De roos NM, Sluijs I, et al. A high menaquinone intake reduces the incidence of coronary heart disease. Nutr Metab Cardiovasc Dis. 2009;19(7):504-10.|
|3.||Fang Y, Hu C, Tao X, Wan Y, Tao F. Effect of vitamin K on bone mineral density: a meta-analysis of randomized controlled trials. J Bone Miner Metab. 2012;30(1):60-8.|
|4.||Hao G, Zhang B, Gu M, et al. Vitamin K intake and the risk of fractures: A meta-analysis. Medicine (Baltimore). 2017;96(17):e6725.|
|5.||Braam LA, Knapen MH, Geusens P, et al. Vitamin K1 supplementation retards bone loss in postmenopausal women between 50 and 60 years of age. Calcif Tissue Int. 2003;73(1):21-6.|
|6.||Carrié I, Portoukalian J, Vicaretti R, Rochford J, Potvin S, Ferland G. Menaquinone-4 concentration is correlated with sphingolipid concentrations in rat brain. J Nutr. 2004;134(1):167-72.|
|7.||Ferland G. Vitamin K and the nervous system: an overview of its actions. Adv Nutr. 2012;3(2):204-12. Published 2012 Mar 2. doi:10.3945/an.111.001784|
|8.||Elder SJ, Haytowitz DB, Howe J, Peterson JW, Booth SL. Vitamin k contents of meat, dairy, and fast food in the u.s. Diet. J Agric Food Chem. 2006;54(2):463-7.|
|9.||Schurgers LJ, Vermeer C. Determination of phylloquinone and menaquinones in food. Effect of food matrix on circulating vitamin K concentrations. Haemostasis. 2000;30(6):298-307.|
|10.||Booth SL, Pennington JA, Sadowski JA. Food sources and dietary intakes of vitamin K-1 (phylloquinone) in the American diet: data from the FDA Total Diet Study. J Am Diet Assoc. 1996;96(2):149-54.|
|11.||Savvidou S, Goulis J, Gantzarou A, Ilonidis G. Pneumobilia, chronic diarrhea, vitamin K malabsorption: a pathognomonic triad for cholecystocolonic fistulas. World J Gastroenterol. 2009;15(32):4077-82.|
|12.||Barros MP, Poppe SC, Bondan EF. Neuroprotective properties of the marine carotenoid astaxanthin and omega-3 fatty acids, and perspectives for the natural combination of both in krill oil. Nutrients. 2014 Mar 24;6(3):1293-317.|
|13.||Pashkow FJ, Watumull DG, Campbell CL. Astaxanthin: a novel potential treatment for oxidative stress and inflammation in cardiovascular disease. Am J Cardiol. 2008 May 22;101(10A):58D-68D.|
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