YOU MAY BE familiar with sources of vitamin C (eat your oranges and bell peppers, people), but unless you’re a nutrition geek, we’re going to go ahead and guess you may not be able to as swiftly tick off foods rich in vitamin K. No more!
“Vitamin K is a critical vitamin in our diets and serves a variety of functions within the body. Interestingly, the term ‘vitamin K’ actually refers to several different fat-soluble vitamins as opposed to just one vitamin as many assume. Although these two vitamins have similar structure and function, their dietary sources, rates of absorption, and bioavailability are different,” says Kristin Gillespie, M.S., R.D., L.D.N., nutrition advisor for Exercisewithstyle.com.
As Gillespie explains, Vitamin K1 is the most common type of vitamin K in the diet and is primarily found in plants, including leafy green vegetables, vegetable oils, and some fruit. Vitamin K2, is found in some animal products and fermented foods, says Gillespie.
“While vitamin K1 must be ingested orally, vitamin K2 can be produced within the body by our intestinal bacteria. The most prominent functions of vitamin K are related to bone health and blood clotting. This vitamin is vital to the synthesis of prothrombin and osteocalcin, proteins that in turn regulate blood clotting and bone metabolism. Beyond these two key health benefits, vitamin K status has also been associated with cognitive health and memory, blood pressure, and risk of heart disease and stroke,” says Gillespie.
“Most Americans are able to get enough of this nutrient between oral ingestion, intestinal absorption, and internal production. However, newborns and individuals with conditions impacting nutrient absorption may be at risk of deficiency,” she cautions, adding that vitamin K deficiency has been linked to osteoporosis, hemorrhage, and excessive bleeding.
Beyond these associations, deficiency is also believed to result in higher blood pressure, as well as increased risk of heart disease and stroke, says Gillespie.
As Kimberly Gomer, M.S., R.D./L.D.N., director of nutrition at Body Beautiful Miami, further elaborates, your healthcare provider may recommend a vitamin K supplement if you fall into any of these categories:
- People who have a disease that affects absorption in the digestive tract, such as Crohn’s disease or active celiac disease
- People who take medications that interfere with vitamin K absorption
- People who are severely malnourished
- Heavy alcohol users
As Gomer highlights, the recommended intake of Vitamin K1 is at least 90 mcg (micrograms) / day for women and at least 120 mcg/day for men and the recommended intake of Vitamin K2 is between 100-300 mcg / day for both men and women. “Those individuals with certain medical conditions may need more, as recommended by their healthcare specialist,” she says. “There are no known serious side effects from taking too much of the vitamin, however researchers have not set a maximum safe dose.”
Below, seven foods to load up on to get your vitamin K fix and help safeguard your health.
Gillespie notes that cooked kale has 531 mcg of vitamin K per ½-cup serving, more than 400 percent of the daily value reference amount to consume (or not to exceed) each day.
Kale is well-known as a nutritional powerhouse, containing many other nutrients, including vitamins A, B6, & C, calcium, potassium, copper, and manganese,” she says.
“Swiss chard is an excellent source of vitamin A and vitamin K and a good source of vitamin C and magnesium,” says Gomer. “Swiss chard also contains the antioxidants beta-carotene, lutein, and zeaxanthin. Vitamin A plays a significant role in normal formation and maintenance of many organs including the heart, lungs, and kidneys.”
If you’re consuming it raw, one 3.5-ounce serving of Swiss chard contains 830 mcg of vitamin K, says Gomer. One cup of cooked Swiss chard packs 477 percent of the daily value.
Another leafy green well worth loading up on.
“Cooked collard greens have 386 mcg of vitamin K per ½-cup serving. This is more than 300 percent of the daily value,” says Gillespie. “Collards are a rich source of several key nutrients, including vitamin C, vitamin A, calcium, folate, and magnesium.”
“Raw spinach contains 145 mcg of vitamin K per 1 cup serving. This is more than 100% of the daily value, but note the larger serving size compared to the other greens listed,” says Gillespie. “Similarly to kale, spinach is widely recognized for its nutrient profile and associated health benefits. Beyond vitamin K, spinach is also rich in vitamin C, carotenoids, folate, iron, and calcium.”
For food high in vitamin K, consider cheeses, too. Especially blue cheese which has 440 mcg of vitamin K (specifically vitamin K2) per 3.5-ounce serving.
“Blue cheese can lower the risk of osteoporosis. Because of its high calcium content, blue cheese can help people achieve healthier bone density,” says Gomer. “It can help in reducing inflammation. Many conditions like arthritis, sinusitis, and asthma cause inflammation, and blue cheese can help relieve people suffering from these problems by reducing inflammation.”
“Cooked broccoli contains 110 mcg of vitamin K per ½-cup serving. This is ~90% of the daily value for this nutrient,” says Gillespie. “Broccoli, similarly to many of these other leafy greens, is rich in many nutrients, including fiber, vitamin C, iron, and potassium. Additionally, it is high in protein compared to most other vegetables.”
“Pork chops contain 59 mcg of vitamin K per three-ounce serving,” says Gillespie, noting that this is about half of the daily value.
“Pork chops are unprocessed and often leaner than other cuts of pork (and other red meats), thus offering a healthier option where meats are concerned,” says Gillespie, adding that other nutrients that pork chops are high in include protein, potassium, vitamin D, vitamin B6, vitamin B12, and calcium.
Perri is a New York City-born-and-based writer; she holds a bachelor’s in psychology from Columbia University and is also a culinary school graduate of the plant-based Natural Gourmet Institute, which is now the Natural Gourmet Center at Institute Of Culinary Education. Her work has appeared in the New York Post, Men’s Journal, Rolling Stone, Oprah Daily, Insider.com, Architectural Digest, Southern Living, and more. She’s probably seen Dave Matthews Band in your hometown, and she’ll never turn down a bloody mary. Learn more at VeganWhenSober.com.