Reviewed by Dietitian Mandy Enright, M.S., RDN, RYT
Credit: PHOTOGRAPHER: BRIE PASSANO, Prop stylist: SAMMY MILA, Food stylist: HOLLY RAIBIKIS
Key Points
Vitamin K supports blood clotting, bone health and heart health by regulating calcium levels.
Leafy greens, fermented foods and animal products are excellent sources of vitamin K.
Cooking vitamin K-rich veggies can enhance nutrient absorption.
You probably know that vitamin C supports your immune system while vitamin D helps strengthen your bones, but you may be scratching your head about the importance of vitamin K. This vitamin doesn’t seem to get as much attention as the others, but it plays a crucial role in your overall health.
“Vitamin K plays an important role in various functions in the body, including blood clotting, bone metabolism and regulating blood calcium levels,” says Erin Palinski-Wade, RD, CDCES. She adds that adequate vitamin K intake supports bone health by improving bone density and reducing fracture risk. Vitamin K also benefits heart health by potentially preventing arterial calcification and, therefore, maintaining lower blood pressure.
Vitamin K exists naturally in two forms: vitamin K1 and vitamin K2. Vitamin K1 is found in plant foods, such as leafy greens. On the other hand, vitamin K2 is produced by intestinal microbiota and found in animal products and fermented foods, including natto (a Japanese dish of fermented soybeans) and cheese, says Edwina Clark, M.S., RD, CSSD. The daily adequate intake (AI) for vitamin K is 120 mcg for males and 90 mcg for females.
Here, we share some of the foods that dietitians recommend as the richest in vitamin K, ranked from highest to lowest.
1. Swiss Chard
Clark notes that a cup of raw Swiss chard provides 299 micrograms of vitamin K1, more than double the daily adequate intake. Swiss chard is also a rich source of fiber, vitamin A, vitamin C, iron, potassium, magnesium and manganese.
2. Collards
A cup of raw collards offers 157 mcg of vitamin K. “Consuming collard greens can help lower LDL cholesterol levels, improve heart health, support bone density, enhance liver health, aid digestion, promote better sleep and contribute to healthier hair and skin due to their nutrient content,” says Palinski-Wade. Try giving your mac & cheese an upgrade by adding in collards to this classic comfort food.
3. Brussels Sprouts
A cup of raw Brussels sprouts contains 156 mcg of vitamin K. It also provides 3.4 g of fiber per serving and 124% of the recommended daily intake for vitamin C, says Clark. Male adults are recommended to consume 90 milligrams of vitamin C daily, while female adults need 75 mg per day. In addition to making a delicious side dish, shredded raw Brussels sprouts make a crunchy salad base.
4. Spinach
Spinach is one of the most commonly known vitamin-K-rich foods, with 1 cup of raw spinach containing 145 mcg. Vitamin K isn’t the only reason why Popeye’s favorite food is this leafy green—spinach is also packed with fiber, antioxidants and vitamins C and A. A simple sautéed spinach makes a quick and easy weeknight side dish.
5. Turnip Greens
Just a half-cup of raw turnip greens yields 138 mcg of vitamin K, which Palinski-Wade says is essential for bone metabolism, vascular health and normal blood coagulation. Since they’re high in fiber and water content, turnip greens also promote digestive health and help prevent constipation. Boost up your usual pesto by using turnip greens for an extra helping of vitamin K.
6. Prunes
One cup of pitted prunes contains 104 mcg of vitamin K, but the bone benefits don’t stop there. “Prunes have vitamins and minerals that seem to work together to protect the bones, including fiber, vitamin K, magnesium, potassium, boron, copper and polyphenols,” says Palinski-Wade. “Research has found that just five to six prunes per day may prevent bone loss.”
7. Broccoli
Broccoli is a nutrient powerhouse, rich in fiber, vitamins A, C and K, says Palinski-Wade, noting that broccoli compounds like sulforaphane may help lower blood sugar, reduce inflammation, protect against cancer, support heart health and boost the immune system. One cup of this cruciferous veggie raw contains 90 mcg of vitamin K. Roast or sauté broccoli and toss in your favorite sauce to reap the benefits.
8. Kale
This nutrient-dense leafy green is rich in vitamins and minerals like vitamins K, C and A. One cup of raw kale provides 82 mcg of vitamin K. “It also contains antioxidants that support immunity, bone health, heart health, cancer protection, eye health and skin and hair health, making it a valuable addition to a healthy diet,” says Palinski-Wade. Don’t think of kale as being something you can only have in a salad or sautéed—try blending some in your next smoothie or toss in the air fryer to make crunchy chips.
9. Kiwi
A cup of this yummy green fruit contains 72.5 mcg of vitamin K. “Kiwifruit is rich in vitamin C and antioxidants, can support immunity, reduce inflammation, promote heart health by lowering blood pressure, aid in digestion with its fiber content and potentially improve sleep quality due to its antioxidant and serotonin contents,” says Palinski-Wade. Add some chopped up kiwi to your favorite salsa for a tropical twist.
10. Asparagus
Eating 100 grams of these green stalks (raw) adds 41 mcg of vitamin K to your diet, not to mention a multitude of other health benefits. Palinski-Wade says these include promoting weight loss due to their low calorie and high fiber content, supporting heart health by lowering blood pressure and aiding in digestion due to their fiber content. We love these stalked roasted or steamed with a drizzle of balsamic glaze and a sprinkle of parmesan.
What to Consider When Eating These Foods
Since vitamin K is a fat-soluble vitamin, it’s best to consume these foods with sources of fat to help increase the absorption of this key nutrient. Consider pairing these foods with some EVOO, eggs (especially the yolks!), or sources of dairy like yogurt and cheese. Plus this helps to enhance their natural flavors.
While you could certainly eat vitamin K-containing foods raw, it’s perfectly OK to cook them, too. “Cooking releases vitamin K and has a positive effect on the vitamin K content of many vegetables,” says Clark, noting that blanching, steaming, roasting, microwaving and stir-frying are generally the best cooking methods for preserving other nutrients commonly found in vitamin K-rich veggies.
When storing vitamin K-rich produce, Palinski-Wade recommends using airtight containers to prevent oxidation and nutrient loss: “It’s best to use dark or opaque colored containers to minimize light exposure, which can speed up nutrient degradation.” If you plan to eat the food over the course of a few days, she recommends keeping it in the refrigerator to slow down the breakdown of nutrients. However, for a longer shelf life, you can cook and freeze leafy greens to maintain the most nutrition.
Can You Eat Vitamin-K-Rich Foods If You Take Blood Thinners?
Vitamin K interacts with some but not all blood thinners. If you’re on anticoagulant medication, consult your doctor for specific vitamin K recommendations. “For some anticoagulants, it’s about consistent vitamin K intake rather than avoiding it altogether,” explains Clark.
Our Expert Take
Vitamin K is a fat-soluble vitamin that is needed for many body functions, from blood clotting and bone metabolism to regulating your calcium levels. These foods, which are rich in vitamin K, can help you get your adequate intake levels. Since these foods are also high in other essential vitamins and minerals, you’ll reap additional benefits when incorporating them into your diet.
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