While many people are pretty familiar with vitamin C, or many of the B vitamins, vitamin K remains a bit of a mystery. Let’s face it, vitamin K isn’t exactly one of the “cool kids” when it comes to popular vitamins. And, most people would find it tough to name any sources of vitamin K. But that doesn’t mean that it’s any less important.
Because while no one was looking, vitamin K has silently been going about some rather lifesaving work.
The Types of Vitamin K
Vitamin K is more of a generic heading for a family of compounds, more specifically referred to as vitamin K1 (phylloquinone) or vitamin K2 (menaquinones).
Vitamin K1 is found primarily in green, leafy vegetables, which is the easiest place to get vitamin K. Vitamin K2 can be found in some animal products, as well as fermented foods. Vitamin K2 can also be produced by bacteria in the human gut.1
So, Why is Vitamin K Important?
There are four main areas where vitamin K tends to shine. They are:
Primarily, vitamin K is known as the “clotting vitamin” – if you don’t get enough vitamin K, your blood won’t clot. As anyone who’s ever had a wound knows, blood clotting is the only thing keeping your blood in your body when a blood vessel is injured.2
Vitamin K has been linked to an improved cognitive function in healthy older adults. One study looked at 320 volunteers between 70-85 years of age. Researchers found that those with the highest blood levels of vitamin K1 were best able to recall their own past life events (times, places, and the emotions they felt at the time).3
With age, a condition called arterial mineralization – where minerals build up in the arteries – becomes much more common. Vitamin K may be able to lower blood pressure and enable the heart to pump easier, by preventing this mineralization.4
Recent studies have found a possible link between vitamin K and strong bones. Research suggests that vitamin K might help with the maintenance of bone strength and bone density, which, in turn, helps protects against bone fractures. This is especially useful for the aging population.5,6
Just how much vitamin K do you need?
The general RDI (recommended dietary intake) is:
- 120mg for adult men
- 90mg for adult women7
However, those who are seen as “at risk” for a vitamin K deficiency are mostly limited to these groups:
- People with malabsorption disorders
- Newborns who have not been treated with vitamin K at birth
Those with malabsorption disorders should speak to their doctor as to whether they should be supplementing their vitamin K.8
The Best Vitamin K Foods
So, let’s get down to the nuts and bolts of things and see whether you’re feeding your body enough wholesome vitamin K foods.
Which foods are the greatest sources of vitamin K?
1. Amaranth Leaves
You may have never heard of amaranth but it’s a delicious leafy veggie. Its leaves are streaked with shades of red and purple, and they go great in a stir-fry in place of your usual suspects, like spinach. Amaranth is also one of the highest sources of vitamin K in the veggie kingdom.
Note: Amaranth grains/seeds should be avoided, however, as they are full of lectins.
Parsley is the ultimate multitasker and can be used to decorate almost any dish. But beyond decoration, parsley is also wonderful in leading roles, like parsley pesto, quiche, or an Italian-style salsa verde sauce. It’s also really simple to grow in a small pot.
Chard, or swiss chard, is often identified by its vibrant red stalks. It’s great sauteed in a little olive or avocado oil, baked into a Gundry-approved pizza, or you can even make a green soup with it.
Kale is already a superstar, and if you’ve never tried it, you really should. Toss kale leaves in olive oil, garlic, and salt and bake as chips, grill kale and serve it under a salmon fillet, or add it to a green smoothie. It’s also wonderful as a basic salad – throw on some sliced almonds and drizzle with a lemon vinaigrette (olive oil, lemon juice, and garlic).
This popular garnish deserves a place as a leading star. Watercress has a lovely, peppery taste, and it’s perfect sauteed, blended into soups, or paired with cooked meat or fish.
Take your spinach game up a notch while getting that vitamin K hit by taking on Dr. Gundry’s creamed spinach recipe.
7. Mustard Greens
Mustard greens come from the mustard plant (the same one we get the mustard seed from). Their peppery flavor can brighten any salad. Pair them wilted with turkey meatballs instead of pasta, or sauté them with garlic and lemon for a delicious side dish.
8. Turnip Greens
Turnip greens allow you to use the whole plant – which can be a rare thing these days! Turn those turnips into a healthy mash (stir in a few tablespoons of grass-fed butter!) and then chop up those leaves for a Southern-style “greens” dish. Cook grass-fed pork in a Dutch oven until crisp, then add turnip greens, onion, and black pepper, and boil for 40 minutes. Yum!
9. Beet Greens
Beet greens are another “whole plant” solution. While you’re baking those vibrant purple beets, chop up the greens and sauté with extra virgin olive oil, garlic, and red pepper flakes.
10. Dandelion Greens
You’ve no doubt encountered a dandelion in your time – perhaps you blew the feathery petals and made a wish as a child? Well, dandelion greens have magical properties as well. They can be delicately sauteed, added to an omelet or frittata, or even made into a dandelion pesto. If you really want to use the entire plant, the roots can even be brewed into a tea.
Other Great Vitamin K Foods
Though not nearly as high in vitamin K as leafy vegetables, there are some other veggies that still contain a substantial amount of vitamin K. These include:
- Brussels sprouts
You can also find good levels of vitamin K in fish, meat, eggs, nuts (especially pine nuts), and Japanese natto (fermented soybeans, so they’re lower in lectins).
If you’re in good health, and your gut bacteria is functioning well, then you probably don’t need to worry too much about a vitamin K deficiency. But it’s always good to make sure that you’re eating a well-balanced diet encompassing all vitamins and minerals. And, if nothing else, you have a much greater menu of leafy greens to add to your cooking repertoire!
But, if you have concerns about a vitamin K deficiency, you should definitely talk to your doctor about vitamin K supplementation and whether it would be right for you.
As a heart surgeon, Dr. Gundry is also a big fan of vitamin K. For more info, you can check out GundryMD’s Essential K2.