By Kurtis Frank and Sol Orwell from Examine.com
What is Vitamin K?
Vitamin K is one of the four fat soluble vitamins in the body, and alongside Vitamin D, works to support bone integrity and structure while also controlling calcium in the body. It is commonly known as a synergist of vitamin D (increasing the benefits of vitamin D on bone tissue), but even by itself vitamin K appears to be highly beneficial to the body.
Why is Vitamin K Important?
Vitamin K is most involved in controlling blood clotting (a deficiency of vitamin K causes hemorrhages) and controlling calcium in the body. High supplemental dosages of vitamin K appear to support bone mineralization and possibly increase bone size alongside definite increases in strength and reductions in fracture risk, and vitamin K can additionally reduce calcification of soft tissue. Calcification of soft tissue is when calcium gets deposited where it should not, and this can lead to instances such as hair loss (if calcium is deposited in hair follicle cells) and stiffened arteries (if deposited on the blood vessel wall) amongst other things.
Vitamin K works through a series of proteins known as ?vitamin K dependent proteins. When vitamin K levels go up, these proteins tend to be more active and the benefits they contribute to the body are what we refer to as the benefits of vitamin K supplementation.
Why Should I Supplement with Vitamin K?
Vitamin K is traditionally recommended to be taken in a variable dose of 60-120mcg daily (depending on where you are located in the world). This recommendation is based on eliminating hemorrhages (historical note: the original RDA for vitamin D was to eliminate rickets. The RDA for Vitamin D at least has been upped as we realize how important it is).
That being said, the above recommendation is just based on one goal. When looking at other goals, such as calcification of soft tissue and bone health, these tend to be maximized at an oral intake of 1,000mcg daily. This is about 10-fold higher than the current recommended intake, and is both safe and appears to maximize the benefits of Vitamin K supplementation.
Like Vitamin D, Vitamin K in the ?ideal? levels is very hard to get via food. In order to get sufficient levels of vitamin K in the diet one must either puree/juice large quantities of kale (fun note: eating kale straight up would not be as effective as it wouldn’t get absorbed well; you need to damage the plant tissue to free it up) or consuming the fermented soy product known as natto. If neither of those are eaten daily, supplementation would be required to bridge the gap.
What Benefits should I Expect?
Over the short term, no noticeable benefits should occur with Vitamin K supplementation. Over the long term there appears to be a greatly reduced risk of fractures and increase in bone integrity that is most potent when paired with Vitamin D and calcium, and the rates of calcification of the arteries are significantly reduced with daily vitamin K supplementation. Since arterial stiffness appears to be a very effective predictor of cardiovascular death, it is reasonable to assume that vitamin K reduces the risk of dying from cardiovascular diseases.
Basically, it’s not a short-term bandaid. But for the long term, it has an amazing set of benefits.
Is it Safe?
Vitamin K appears to be remarkably safe. A large body of research from Japan had people using 45mg of vitamin K2 daily for up to two years. Even at 45,000% of the recommended daily intake, there was no toxicity issues.
So yes, 1mg/day is very safe.
What Form do I Need?
Vitamin K comes in two forms, K1 and K2.
K1 is known as phylloquinone, and is the plant based form of vitamin K.
K2 is a series of molecules known as menaquinones, and are based in animal or bacterial products. They differ by how long a side-chain is, and these menaquinones (MK) are designated as such. MK-4 is a menaquinone with four groups in its sidechain, MK-7 has seven groups.
All forms of vitamin K appears to be effective in increasing vitamin K status of the body, and the 1000mcg recommendation was based on K1. Either K1 or MK-7 are recommended for daily supplementation, as, although MK-4 is also effective, it spends less time in the body and needs a higher dose to be equivalent to MK-7.
Our General Recommendations
Vitamin K (by virtue of being a vitamin) is an essential part of anyone’s diet. Similar to how the RDA for vitamin D was found to be too low, the RDA for vitamin K is too low to fully unlock its optimal benefits.
Unless one is eating natto or frequently blending kale-drinks, supplementation is the way to go to fully unlock vitamin K’s benefits. We recommend you take it with vitamin D, and calcium if you don’t get enough of that (calcium is a lot easier to get via diet).
We’ve been making sense of scientific research on supplementation and nutrition for the past 2.5 years. An independent organization, we recently released The Supplement-Goals Reference Guide, which lets you quickly and easily identify supplements that would be a useful addition to your particular health goals. All backed and cited with scientific papers.