Vitamin Okay is considerably of an unsung hero amongst nutritional vitamins. We regularly overlook it, but we couldn’t survive with out it. Do you know that with out it, even the smallest damage might trigger us to bleed out? One in all its major roles is blood clotting. Many individuals turn out to be all for it when their physician prescribes blood-thinning drugs.
Nonetheless, that is removed from its solely operate. Immediately, we’ll discover different very important processes that require it, which meals are richest in vitamin Okay, and why Japanese folks, with diets wealthy in fermented meals, have a decrease threat of osteoporosis. [7,9]
On this article, you’ll study vitamin Okay’s affect on:
What’s Vitamin Okay?
Vitamin Okay is likely one of the important fat-soluble nutritional vitamins (others embody vitamin D, A, and E). In comparison with its counterparts, it’s typically sidelined and never regularly mentioned. That’s a disgrace as a result of this nutrient actually helps maintain our our bodies collectively. It performs a major position in essential features, reminiscent of serving to keep robust and resilient bones, and it permits our blood to clot. In follow, which means that after we get injured, the wound heals and prevents the physique from dropping extreme blood. [3]
You is perhaps stunned to be taught that the time period vitamin Okay doesn’t seek advice from only one substance. It’s truly a group of compounds with comparable buildings. In vitamin, we’re most all for two major kinds: vitamin K1 (phylloquinone) and vitamin K2 (menaquinone). To complicate issues, vitamin K2 has a number of subtypes, particularly MK-4, MK-7, MK-8, MK-9, and others.
There’s additionally vitamin K3 (menadione), however it’s not the ultimate energetic type of the vitamin. Primarily, it’s an intermediate in vitamin Okay metabolism. [3]
What Is the Distinction Between Vitamin K1 and K2?
We’ve already talked about that these two types of vitamin Okay differ of their construction. Nonetheless, the important thing distinction lies of their origin. Moreover, one is extra bioavailable and simpler for the physique to utilise than the opposite.
Vitamin K1 (Phylloquinone)
Roughly 75–90% of the vitamin Okay we devour comes within the type of vitamin K1, also referred to as phylloquinone. It’s primarily present in plant-based meals, with the best concentrations in leafy inexperienced greens (reminiscent of spinach, kale, cabbage, and many others.). It’s also current in vegetable oils and a few nuts. Afterward, we’ll focus on the very best meals sources and the way a lot vitamin Okay they comprise. [10]
Nonetheless, this manner has one main disadvantage—it’s comparatively tough for the physique to soak up. In crops, vitamin K1 is tightly sure to chloroplasts (the cell buildings answerable for photosynthesis). Consequently, solely about 5–10% of dietary vitamin K1 is absorbed. Fortuitously, pairing these meals with fats can enhance absorption as much as threefold. In follow, which means that drizzling your salad with a tablespoon of olive oil or sprinkling it with seeds can considerably improve the uptake of vitamin K1. The best strategy to get hold of bioavailable phylloquinone is thru dietary supplements. [3,10,14]
Vitamin K2 (Menaquinone)
Menaquinone is kind of distinctive in its origin—it’s produced by micro organism, together with these in our digestive system. Sure, that’s proper—useful microorganisms that make up our gut microbiome are able to synthesising vitamin Okay.
Micro organism additionally generate vitamin K2 throughout fermentation, which is why fermented meals reminiscent of natto (fermented soybeans) and pickled greens are wonderful sources. Moreover, sure micro organism within the intestines of animals convert vitamin K1 into vitamin K2, particularly the MK-4 subtype. Because of this animal-based meals may function good sources of vitamin K2. [3]
Not like vitamin K1, menaquinone is extra bioavailable and higher absorbed by the physique. Nonetheless, the absorption price depends upon the particular subtype of menaquinone—MK-7 is essentially the most effectively absorbed. This is applicable to each dietary sources and dietary supplements, with the latter providing practically full absorption of the administered dose. [3,10]
Vitamin K3 (Menadione)
Regardless of its identify, this compound isn’t truly a vitamin. Menadione is classed as a provitamin, that means that it undergoes conversion within the physique to turn out to be an energetic vitamin. Particularly, it serves as an intermediate within the course of the place vitamin K1 (phylloquinone) is transformed into MK-4 (a kind of vitamin K2). On this course of, phylloquinone first transforms into menadione, which is then transformed into MK-4. Nonetheless, in people, this conversion is inefficient and never effectively understood, whereas it seems to be simpler in animals. [3,12]
Menadione was as soon as synthetically produced and utilized in dietary dietary supplements, as researchers initially believed it might function an efficient different to nutritional vitamins K1 and K2. Nonetheless, it didn’t work as anticipated and even led to well being problems. Consequently, it’s not utilized in fashionable dietary dietary supplements.
A Fast Abstract of Key Variations Between Types of Vitamin Okay
|
Vitamin K1 (Phylloquinone) |
Vitamin K2 (Menaquinone) |
Vitamin K3 (Menadione) |
|
|---|---|---|---|
| Origin | Plant-based | Bacterial / MK-4 is shaped from phylloquinone conversion | Intermediate product within the conversion of vitamin K1 to K2 / Artificial |
| Sources | Plant-based meals, dietary dietary supplements | Fermented meals, animal-based meals, manufacturing by intestine micro organism, dietary dietary supplements | Not present in meals or dietary supplements, unsuitable for supplementation |
| Main Features within the Physique | Blood clotting | Bone metabolism, cardiovascular well being | |
| Bioavailability | Low (5–10% absorption from meals, will increase when consumed with fat), good absorption from dietary supplements | Virtually absolutely absorbed from each meals and dietary supplements | Not appropriate for supplementation |
Which Type of Vitamin Okay Is Higher?
It will actually be simpler if one type of vitamin Okay have been simpler and useful in order that we might concentrate on it in our food regimen. Sadly, that’s not the case. Vitamin K1 and K2 don’t operate within the physique in the identical means, and every supplies totally different well being advantages. They complement one another completely, and it’s important for us to get sufficient of each.
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What Are the Well being Advantages of Vitamin Okay?
We are able to make sure that vitamin Okay isn’t current in our our bodies simply by likelihood—it performs an important position in lots of life-sustaining processes. Curiously, every type of vitamin Okay has its personal specialisations, focusing extra on sure features than others.
1. It Permits Blood Clotting
Vitamin Okay, particularly vitamin K1 (phylloquinone) and MK-4 (a kind of vitamin K2), are key gamers in blood clotting. This course of is extremely necessary for our survival. Whenever you hear “blood clotting,” chances are you’ll instantly consider thrombosis and blocked arteries brought on by blood clots, however these are excessive instances that happen when one thing goes mistaken within the physique.
In on a regular basis life, blood clotting serves a number of essential features, together with these necessary ones:
- Stopping extreme bleeding when blood vessels are broken. Even a minor damage might trigger steady bleeding if the physique have been unable to type a blood clot on the wound website.
- Defending in opposition to infections. A sealed wound prevents dangerous microorganisms from coming into the bloodstream.
- Selling wound therapeutic. The blood clot acts as a short lived barrier till the broken tissue can regenerate. [6]
How Does Vitamin Okay Assist Blood Clotting?
For a blood clot to type and seal a broken blood vessel, a number of key steps should happen. Think about slicing your finger—your physique instantly mobilises its emergency response groups. The primary motion is to constrict the blood vessels to gradual blood movement. On the identical time, platelets rush to the positioning of the damage and create a momentary plug. That is the place vitamin Okay steps in.
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Vitamin Okay sends a sign to the clotting (coagulation) elements, instructing them to start out their a part of the rescue operation. Clotting elements are specialised proteins that assist create a everlasting plug to seal the wound. [17]
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Vitamin Okay particularly prompts 4 clotting elements, one in every of which is prothrombin. As soon as activated, prothrombin is transformed into thrombin, which then facilitates the conversion of fibrinogen into fibrin—the first structural element of the everlasting clot. [5,12]
- In brief, vitamin Okay prompts coagulation elements, permitting the physique to finish the clotting course of and correctly seal the wound.
How Do Blood-Thinning Medicines Have an effect on This Course of?
You’ve in all probability heard that individuals taking blood thinners, significantly Warfarin, want to observe their vitamin Okay consumption, each from meals and dietary supplements. It’s because Warfarin and vitamin Okay basically work in opposition to one another. When somebody wants blood thinners, it means their blood is just too susceptible to clotting, rising the danger of harmful clots that might block blood vessels. To forestall this, medical doctors prescribe Warfarin, which reduces extreme blood clotting.
Nonetheless, as we’ve already mentioned, vitamin Okay does the alternative—it promotes clotting. If somebody consumes an excessive amount of vitamin Okay, it might intrude with the medicine, making it much less efficient. Because of this people on blood thinners ought to seek the advice of their physician and a nutritionist about their food regimen and vitamin Okay consumption. A physician can use a prothrombin time take a look at to measure how lengthy it takes for blood to clot. Together with different exams, they’ll tailor the fitting therapy and monitor it over time. A nutritionist can then present steering on how one can keep a balanced food regimen whereas maintaining vitamin Okay consumption underneath management. [3]
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2. Helps Bone Energy
Vitamin Okay is likely one of the important micronutrients wanted for bone progress, power, sturdiness, and general well being. Whereas vitamin K1 performs the dominant position in blood clotting, vitamin K2 is extra essential for sustaining robust bones. So what precisely does this nutrient do day by day to assist our skeletal system?
- The physique wants vitamin Okay for the manufacturing of osteocalcin, a protein produced by bone cells (osteoblasts). This protein promotes bone mineralisation, guaranteeing they continue to be robust and much less susceptible to fractures. By supporting this course of, vitamin Okay can assist fight osteoporosis (bone density loss. [1]
- Vitamin Okay helps the progress of bone cells (osteoblasts), which contribute to bone formation and improvement.
- It slows down the lack of bone mass by inhibiting osteoclasts—cells answerable for breaking down bone tissue. Whereas this course of happens naturally all through life, it stays balanced with new bone formation till in regards to the age of 25–30. After this level, bone loss begins to outweigh new bone progress. This makes it much more necessary to maintain bone well being, and vitamin Okay helps decelerate this pure decline. [1]
How Does Vitamin Okay Work with Calcium and Vitamin D?
With regards to constructing robust, wholesome bones, vitamin D and calcium play equally necessary roles alongside vitamin Okay. Calcium is the main constructing block of bones, offering structural power. Nonetheless, it can not attain the bones by itself. It wants vitamin D to facilitate calcium absorption from meals and stimulate the manufacturing of osteocalcin, the protein that helps deposit calcium into bones. As soon as osteocalcin is produced, vitamin Okay steps in to activate it, permitting calcium to combine into bone tissue. This cooperation between vitamins D and K ensures that calcium is effectively used to strengthen bones. [2]
For those who’re all for studying extra about what causes vitamin D deficiency, its different well being advantages, how a lot you want day by day, and the place to get it, take a look at our article: Vitamin D: Why It’s So Important, What Deficiency Causes, and How to Supplement It.
3. Improves Cardiovascular Well being
The position of vitamin Okay in coronary heart and vascular well being is commonly neglected. Nonetheless, vitamin Okay—particularly within the type of menquinone —helps shield blood vessels from undesirable calcification. It prompts a particular protein referred to as Gla-protein, which will be regarded as a guardian of the arteries. This protein prevents calcium from accumulating the place it shouldn’t. By maintaining blood vessels clear and versatile, vitamin Okay helps scale back the danger of atherosclerosis (hardening of the arteries) and different cardiovascular illnesses. [4,13]
4. Different Well being Advantages of Vitamin Okay
- Has anti-inflammatory results, based on research.
- It appears that evidently it could possibly enhance insulin sensitivity.
- Increased consumption has been linked to a decrease threat of sure cancers, based on researchers.
- Could play a job in supporting cognitive features. [1,3]
What Occurs When You Have a Vitamin Okay Deficiency and Who Is at Danger?
After studying about its features, you may in all probability already guess what occurs when vitamin Okay ranges are too low. A deficiency on this vitamin can result in a number of critical well being points.
- Decreased blood clotting, resulting in extreme bleeding.
- Weaker bones and decrease bone density, rising the danger of osteoporosis.
- A better threat of atherosclerosis. [3,14]
The excellent news is that vitamin Okay deficiency is uncommon in wholesome people. Nonetheless, sure teams are extra in danger.
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Newborns – Throughout being pregnant, vitamin Okay doesn’t effectively go by the placenta to the newborn. Moreover, breast milk comprises little or no vitamin Okay. Because of this newborns are routinely given a vitamin Okay injection shortly after start. Another is an oral complement given over a number of weeks, however this can be much less efficient. Consequently, world medical suggestions favour the injection. [8,10,11]
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Individuals with nutrient absorption issues – These with situations affecting the digestive system, reminiscent of coeliac illness or inflammatory bowel illness (IBD), might battle to soak up vitamin Okay correctly.
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Sufferers on long-term antibiotics – Antibiotics kill useful intestine micro organism, which play a job in producing vitamin Okay.
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Individuals with chronically low dietary consumption – This will embody these with eating disorders or people following long-term restrictive diets.
People with sure liver illnesses and different particular well being situations.
Can Extra Vitamin Okay Have Undesirable Results?
For vitamin K1 and K2, no poisonous results from extreme consumption have been noticed in wholesome people. Nonetheless, as beforehand talked about, vitamin Okay can intrude with blood-thinning drugs, probably decreasing their effectiveness. [3]
Which Medicines Work together with Vitamin Okay?
When taking sure drugs, vitamin Okay consumption must be carefully monitored, as it might probably scale back their effectiveness. Conversely, some drugs can decrease vitamin Okay ranges within the physique. Which of them are these?
- Warfarin and comparable prescription blood thinners (vitamin Okay antagonists) – Vitamin Okay can scale back the effectiveness of those drugs, resulting in elevated blood clotting. Nonetheless, this doesn’t apply to heparin or low-molecular-weight heparins, which don’t require vitamin Okay restriction.
- Bile acid sequestrants, a kind of cholesterol-lowering drug – These scale back bile acid absorption, which in flip impacts vitamin Okay absorption. This can lead to decrease vitamin Okay ranges within the physique.
- Orlistat, a weight-loss medication – It reduces fats absorption from meals. Since vitamin Okay is fat-soluble, this may result in a decrease consumption of the vitamin.
- Antibiotics, which get rid of micro organism within the digestive system – Some antibiotics may destroy useful micro organism that produce vitamin Okay. [16]
The place Can We Get Vitamin Okay?
We’ve already talked about the principle sources of vitamin Okay. Now, let’s take a better have a look at which meals comprise totally different types of vitamin Okay, their vitamin content material, and the very best dietary sources.
Which Meals Are Good Sources of Vitamin K1?
Usually, vitamin K1 is present in plant-based meals. Listed below are a number of the richest sources:
- Leafy inexperienced greens – The very best vitamin Okay content material is present in spinach, kale, lettuce, and cabbage. You may as well use spinach or kale powder in cooking, baking, or smoothies. [10]
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Cruciferous greens, reminiscent of broccoli.
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Wild inexperienced crops, together with nettles, dandelion leaves, and wild garlic.
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Herbs used as seasonings, reminiscent of marjoram, basil, and savoury.
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Vegetable oils – Soybean, rapeseed, and olive oil are the richest sources of vitamin Okay.
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Fruits – Blueberries, kiwi, and grapes comprise notable quantities of vitamin Okay. [10]
To summarise, nearly any vegetable or fruit might comprise some vitamin Okay. The identical goes for oils, nuts, and seeds. Nonetheless, the meals listed above have the best concentrations. If somebody must restrict vitamin Okay consumption, an much more detailed dietary evaluation could also be crucial.
The vitamin Okay content material in meals may fluctuate relying on age, farming strategies, and local weather situations.
How Does Cooking and Daylight Have an effect on Vitamin K1 Content material?
You is perhaps questioning whether or not we unintentionally destroy a number of the vitamin Okay in meals. If that have been the case, it could be an actual disgrace. The reality is that sure cooking strategies can scale back vitamin Okay ranges, however fortuitously, there are easy methods to stop this.
The excellent news is that common cooking doesn’t considerably destroy vitamin Okay in meals—or at most, solely to a minimal extent. Nonetheless, long-term heating at temperatures above 185°C can scale back its content material. This may occur, for instance, throughout baking. In accordance with analysis, vitamin Okay content material can lower by about 15% if uncovered to this temperature for greater than 40 minutes. [10]
Whereas warmth doesn’t have a significant affect on vitamin Okay, it’s extremely delicate to daylight. That is particularly necessary in terms of oils, as they’re typically not saved correctly. Would you imagine that if an oil is uncovered to sunlight for simply two days, its vitamin Okay content material can drop by 46–87%? To forestall this, oils must be saved in darkish containers and ideally saved in a darkish place.
Vitamin K1 Content material in Numerous Meals
|
Meals |
Vitamin K1 Content material per 100 g |
|---|---|
| Rainbow chard | 830 µg |
| Spinach | 483 µg |
| Kale | 390 µg |
| Broccoli | 102 µg |
| Romaine lettuce | 83 µg |
| Marjoram (dried) | 622 µg |
| Basil (dried) | 1710 µg |
| Soybean oil | 184 µg |
| Rapeseed oil | 71 µg |
| Olive oil | 60 µg |
| Hazelnuts | 14 µg |
| Blueberries | 19 µg |
| Raspberries | 9 µg |
[18]
Which Meals Comprise Vitamin K2?
As talked about earlier, vitamin K2 has two major sources. It’s produced by micro organism in our intestine microbiome and may also be obtained from meals.
- Fermented meals are significantly wealthy in vitamin K2 since they’re produced by bacterial fermentation. Throughout this course of, particular useful microorganisms convert sugars and different vitamins into useful compounds, together with vitamin Okay. Nonetheless, not all micro organism produce vitamin Okay, so the quantity depends upon the strains utilized in fermentation.
- Vitamin K2 will be present in fermented cabbage (sauerkraut), kimchi, or kombucha. The Japanese dish natto is especially wealthy in vitamin K2, and analysis means that common consumption of natto is linked to a decrease threat of osteoporosis. [7,9]
- Cheese can also be supply of vitamin K2, as it’s produced by fermentation. Research point out that roughly half of the vitamin K2 consumption in a typical combined food regimen comes from cheese. [10]
- Liver and liver merchandise comprise excessive quantities of vitamin K2.
- Different animal merchandise – together with meat, processed meats, and eggs. Since animals additionally synthesise vitamin K2 of their intestines, it accumulates of their tissues. Moreover, intestine micro organism in animals can convert vitamin K1 from plant-based meals into vitamin K2 (MK-4, for instance). Because of this hen meat and eggs can present this vitamin for our our bodies.
Vitamin K2 Content material in Numerous Meals
|
Meals |
Vitamin K2 Content material per 100 g |
|---|---|
| Cheese and dairy merchandise | 0.1 – 94 µg |
| Liver | 0.3 – 369 µg |
| Sauerkraut | 13 µg |
| Natto | 350 – 1000 µg |
| Chicken meat | 5.8 – 60 µg |
| Eggs | 10 – 30 µg |
[3]
Who Can Profit from Vitamin Okay Supplementation?
By now, you recognize that newborns, folks with particular well being situations, and people taking sure drugs might require vitamin Okay supplementation. In these instances, a physician determines the necessity for supplementation and ensures correct dosing. However what about wholesome people? Who ought to contemplate taking vitamin Okay dietary supplements as a part of their routine?
- Individuals with inadequate dietary consumption of vitamin Okay – This will embody vegetarians and vegans, who devour much less vitamin K2, in addition to these following keto diets, who might not get sufficient vitamin K1 resulting from restricted fruit, vegetable, and plant-based meals consumption.
- People with long-term low-calorie consumption – A restricted food regimen typically results in decrease general nutrient consumption.
- Athletes – As a consequence of larger nutrient calls for and elevated pressure on their musculoskeletal system, they could profit from vitamin Okay’s position in bone well being.
- These trying to stop osteoporosis – For this case, a combination of vitamin K2 and D3 is especially useful.
- People involved about cardiovascular well being.
- Postmenopausal ladies – This group is at a better threat of osteoporosis.
- Individuals taking excessive doses of calcium or vitamin D – Vitamin Okay helps steadiness these vitamins within the physique and ensures their correct operate.
What Is the Really useful Each day Consumption of Vitamin Okay
European Meals Security Authority (EFSA):
- 70 µg for wholesome adults, together with pregnant and breastfeeding ladies
German Diet Society (DACH):
- 70 µg for males
- 60 µg for girls, together with pregnant and breastfeeding ladies [3,15]
For simplicity, these advisable values are based mostly on phylloquinone (vitamin K1). Nonetheless, in follow, the entire vitamin Okay consumption additionally consists of menaquinones (vitamin K2).
For those who’re curious in regards to the results and advantages of different nutritional vitamins, take a look at our article The Complete Guide to Vitamins: Their Functions, Deficiency Symptoms, and Recommended Intake.
What’s the lesson?
Vitamin Okay might not get as a lot consideration as nutritional vitamins D or C, however it performs an important position in our our bodies, significantly in blood clotting, bone well being, and vascular safety. Guaranteeing sufficient consumption of each K1 and K2 is crucial for optimum well being. The easiest way to acquire vitamin Okay is thru a balanced and diversified food regimen. Leafy inexperienced greens present vitamin K1, whereas fermented meals and animal merchandise provide vitamin K2. If wanted, dietary supplements can assist keep wholesome ranges, permitting you to totally profit from this important vitamin.
Vitamin Okay is crucial—unfold the phrase! Don’t maintain this data to your self—share it together with your family and friends to allow them to additionally study the advantages of vitamin Okay!
Sources:
[1] AKBARI, S. – RASOULI-GHAHROUDI, A.A. Vitamin Okay and Bone Metabolism: A Overview of the Newest Proof in Preclinical Research. https://pubmed.ncbi.nlm.nih.gov/30050932/][
[2] BALLEGOOIJEN, A.J. VAN et al. The Synergistic Interaction between Nutritional vitamins D and Okay for Bone and Cardiovascular Well being: A Narrative Overview. – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613455/
[3] EFSA PANEL ON DIETETIC PRODUCTS, NUTRITION AND ALLERGIES (NDA) et al. Dietary reference values for vitamin Okay. – https://data.europa.eu/doi/10.2903/j.efsa.2017.4780
[4] HARIRI, E. et al. Vitamin K2-a uncared for participant in cardiovascular well being: a story assessment. – https://pubmed.ncbi.nlm.nih.gov/34785587/
[5] HARUTYUNYAN, H.A. Prothrombin and fibrinogen carbonylation: How that may have an effect on the blood clotting. – https://pmc.ncbi.nlm.nih.gov/articles/PMC6837719/
[6] HOU, Y. et al. Platelets in hemostasis and thrombosis: Novel mechanisms of fibrinogen-independent platelet aggregation and fibronectin-mediated protein wave of hemostasis. – https://pubmed.ncbi.nlm.nih.gov/26541706/
[7] IKEDA, Y. et al. Consumption of Fermented Soybeans, Natto, Is Related to Decreased Bone Loss in Postmenopausal Girls: Japanese Inhabitants-Primarily based Osteoporosis (JPOS) Study1. – https://www.sciencedirect.com/science/article/pii/S0022316622082499
[8] JULLIEN, S. Vitamin Okay prophylaxis in newborns. – https://pmc.ncbi.nlm.nih.gov/articles/PMC8424792/
[9] KOJIMA, A. et al. Natto Consumption is Inversely Related to Osteoporotic Fracture Danger in Postmenopausal Japanese Girls. – https://jn.nutrition.org/article/S0022-3166(22)02079-X/fulltext
[10] MLADĚNKA, P. et al. Vitamin Okay – sources, physiological position, kinetics, deficiency, detection, therapeutic use, and toxicity. – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8907489/
[11] LOEWY, A.D. Place Assertion: Tips for vitamin Okay prophylaxis in newborns: A joint assertion of the Canadian Paediatric Society and the Faculty of Household Physicians of Canada. – https://pmc.ncbi.nlm.nih.gov/articles/PMC6184976/
[12] SHEARER, M.J. – OKANO, T. Key Pathways and Regulators of Vitamin Okay Operate and Middleman Metabolism. – https://pubmed.ncbi.nlm.nih.gov/29856932/
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