Vitamin K. It’s one of those vitamins that people know they probably need, but aren’t entirely sure why. That’s in part due to the fact that vitamin K is actually a group of vitamins, adding to the general confusion over which K does what to support your health. To demystify the underappreciated vitamin K, I’ve put together my 4-point cheat sheet on this powerful substance that everyone deserves to get to know better:
What is Vitamin K?
Unlike many vitamins, vitamin K is more than a solo act, it actually refers to a handful of similarly-structured, fat-soluble vitamins that our bodies need in order to facilitate blood coagulation, manage blood calcium levels and support heart, brain and bone health. Under the vitamin K umbrella is the single-molecule vitamin K1 or phylloquinone, and the multi-molecule K2 or menaquinone. Vitamin K1 is perhaps best known for the key role it plays in assisting with the production of vital clotting factors; whereas vitamin K2 is integral to activating the essential proteins that help keep calcium out of your arteries, where you don’t want it, and transporting calcium to your bones, where it’s needed to keep them strong.
What’s in it for you: three big benefits
When you’re getting enough vitamin K, studies indicate you’re going a long way to strengthen bones and teeth; help protect against fractures; and even reduce the risk level for osteoporosis, which seems to be closely correlated with low vitamin K levels.
When it comes to your brain, vitamin K looks to offer cognitive benefits as well. A recent study linked higher levels of vitamin K with better memory performance in older adults and another study indicated that it may also be helpful for Alzheimer’s prevention.
What’s in it for your heart? For starters, higher vitamin K2 intake is associated with lowered heart disease risk. Studies suggest that Vitamin K may do that by preventing mineral build-up in the arteries – which in turn promotes better blood flow and may also reduce stroke risk.
How to get your Ks?
For vitamin K1, think plants, our primary dietary source of the stuff. Look for (preferably organic or farmers’ market) cruciferous veggies and leafy greens like kale, Swiss chard, cabbage, Brussels sprouts, broccoli, spinach, kale parsley, mustard, collard and beet greens to name a few.
And, as if you needed one more reason to love your leafys, studies indicate that some K2 is actually made by the bacteria in your gut, that is, if you feed them right. Those bacteria thrive on K1-rich leafy greens and help convert some of that good K1 stuff into K2. Pretty cool, eh?
Another way to eat your K2s is by including healthy, grass-fed or pasture-raised animal sources and some fermented foods on your plate. A few good animal sources include dairy products from grass-fed cows; egg yolks; and organ meats like pork, beef, chicken and goose liver.
On the fermented food front, natto, the Japanese snack food staple made from fermented soy, ranks highest, but you can also get your K2s in smaller amounts by digging into fermented classics like sauerkraut, tempeh, and kombucha.
To boost absorption of your vita Ks, be sure to add some dietary fat to your plate as well. The easiest way to get the boost is by topping your leafys with extra virgin olive oil, nuts or seeds.
How much is enough?
There’s little need to be concerned about exceeding the daily dose recommendation for vitamin K from eating a healthy, plant rich diet. While suggested daily amounts vary a bit based on age and gender, in general, a good number to shoot for is roughly 120 micrograms per day for adults. In real food terms, that translates to roughly a half cup of raw broccoli, cooked cabbage or Brussels sprouts.
Where you need to be a bit more careful is with vitamin K supplementation. Though it’s great for filling in nutritional gaps, vitamin K supplementation should be done under your doc’s supervision, as overdoing it in pill form can interact negatively with some drugs. For example, vita K supplements can interfere with every-day prescriptions like blood thinners, antibiotics, and cholesterol-lowering meds.
So, if you’re on one (or more) of the aforementioned or, for that matter, any prescription meds, check with your doctor first to get the all clear. Once you and your doctor have determined that a supplement is appropriate for your situation, look for a combination supplement for optimal benefits like one with Vitamin K2, vitamin D, calcium, and magnesium.