Best Vitamin K Supplement: Complete Guide for 2025

You’ve probably heard lots about vitamins A, C, vitamin D3, zinc, magnesium, and iron, but have you heard much about vitamin K?

Not likely.

Although equally as important as the other essential vitamins and minerals, most people forget about K—it’s pretty rare in the Western diet, and health professionals typically don’t educate us on the importance of this fat-soluble nutrient.

But vitamin K is essential for optimal physiological performance and plays a vital role in bones, the cardiovascular system, insulin regulation, and much more.

If you’re unfamiliar with this nutrient, we’re breaking down the ins and outs of vitamin K, also known as “koagulations vitamin.”

We’ll cover what it is, the benefits of vitamin K, vitamin K deficiency signs and symptoms, and how to get enough vitamin K1 and vitamin K2 in your diet to keep your vitamin K levels up to par.

Vitamin K1 vs. Vitamin K2

So, what’s the actual difference between vitamin K1 and vitamin K2? Aside from naturally existing in different foods, they elicit different functions. And in terms of supplementation, one may be more effective than the other.

As we mentioned before, naturally occurring vitamin K compounds inherent to plant foods are called phylloquinone (vitamin K1).

In contrast, vitamin K2 is naturally found in animal-based products and fermented foods—on top of several bacterial-derived menaquinones (MKs) synthesized in the gut ⁵.

Although the basic structure of all vitamin K compounds is similar, the side chains differentiate them. These side chains dictate how they are metabolized—transport, target tissue uptake, and excretion.

While vitamin K1 only comes in one form, phylloquinone, there are several menaquinones (vitamin K2).

The ones you’ll want to know about are short-chain MK-4 (eggs, meat, liver) and long-chain menaquinones MK-7, MK-8, MK-9, and MK-10 (cheese, curd, sauerkraut, natto) ⁶.

We’ll cover the benefits of vitamin K in a minute, but as we said, vitamin K1 and vitamin K2 don’t have the same functions. Menaquinones like MK-7 are more heavily involved in the blood coagulation cascade than K1 or MK-4 ⁶.

And compared to K1, MK-7 has a longer half-life, which means it elicits its effects more long-term effect. However, studies also show that K2 is involved in bone health and cardiovascular function.

The Benefits Of Vitamin K

Supports healthy bones

Calcium and vitamin D are the two nutrients that come to mind when you think about bone health.

But don’t shun vitamin K just yet! Vitamin K plays an essential role in bone integrity and strength through its involvement in calcium metabolism—yep, you read that right (it’s not just vitamin D and magnesium that are needed).

Vitamin K2 is required to activate two calcium-binding proteins: matrix GLA protein (MGP) and osteocalcin, which are involved in building and maintaining bone tissue ^{7, 8}.

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Many mechanisms drive vitamin K’s action on bone health, but there are two key ones we want to emphasize:

The gamma-carboxylation of osteocalcin, an essential protein involved in bone mineralization, and bone mineral density.

Vitamin K’s effect on calcium homeostasis

On top of these two functions, vitamin K also plays a vital role in regulating genetic transcription of osteoblastic markers⁹

• Suppressing bone resorption
• Regulating the formation of osteoclasts
• Low levels of vitamin K interfere with the activation of osteocalcin and decrease the activity of osteoblasts (bone-building cells), which increases the risk of osteoporosis and vascular calcification ¹⁰.
• Prevents vascular calcification and improves cardiovascular health

Vascular calcification refers to the deposition of minerals in the walls of blood vessels (arteries and veins).

It can take on several forms, but in any case, it’s associated with several chronic diseases, including atherosclerosis, diabetes, certain heredity conditions, and kidney disease ¹¹.

People with vascular calcification have an increased risk of cardiovascular events, which create issues with blood flow to organs and tissues.

While dietary and lifestyle factors can make a big difference in cardiovascular health, so can vitamin K supplementation. Vitamin K, specifically vitamin K2 is required by the enzyme gamma-glutamate carboxylase to convert Matrix Gla protein (MGP) into its active carboxylated form ¹².

When activated, MGP inhibits calcification. Although the exact mechanism isn’t clear, several studies support the role of vitamin K in heart health. One study found that expression of under-carboxylated MGP was linked to vascular calcification and a higher risk of cardiovascular mortality.

However, vitamin K2 supplements increased levels of carboxylated MGP, which could prevent vascular calcification and any associated risks or outcomes.

May improve insulin sensitivity

Although you may not link vitamin K to improved glucose regulation, it turns out that it can! Studies point to a beneficial effect of vitamin K on insulin sensitivity, metabolic syndrome, glucose homeostasis, and reducing the risk of diabetes ¹³.

Vitamin K has also been shown to cytokines and inflammatory markers, which are implicated in the pathology of insulin sensitivity.

The exact mechanisms as to how vitamin K influences insulin sensitivity isn’t clear, but some experts suggest that the vitamin K-dependent bone protein, osteocalcin, mediates the endocrine pathway.

This pathway then influences insulin sensitivity through pancreatic β cells, promoting their proliferation, and increasing insulin secretion.

Promotes blood coagulation

But the most popularized role—and what initially caused the discovery of the fat-soluble vitamin K—is in blood clotting or hemostasis.

It is required to form 13 proteins needed for the coagulation cascade, which is necessary to put the breaks on bleeding.

They can be broken down into four categories based on conditions they’re associated with ¹⁴:

• Only with bleeding (FX deficiency)
• Both bleeding and thrombosis (FII, FVII, and FIX)
• Only with thrombosis (protein C and protein S)
• No association with either bleeding or thrombosis (protein Z)

For your body to stop bleeding, it requires all of these proteins. A deficiency of vitamin K is classified as an acute, life-threatening condition due to excessive bleeding.

Vitamin K deficiency + signs and symptoms

Although a vitamin K deficiency is less common than a deficiency of other nutrients, it can happen—and signs aren’t the most obvious.

Here are some of the reasons for a vitamin K deficiency ¹⁵:

• Neonatal deficiency
• Hereditary combined with vitamin K-dependent clotting factors deficiency (VKCFD)
• Inadequate vitamin K absorption due to a chronic disorder
• Drug-related

Coumarin, an anticoagulant more commonly known as Warfarin, can lead to decreased production of the proteins involved in blood clotting.

At the same time, some broad-spectrum antibiotics can cause the body to produce less vitamin K or interfere with its efficacy.

A vitamin K deficiency can also occur in people with fat absorption issues, as it's part of the fat-soluble vitamins and requires the presence of fat for absorption.

Some of these disorders include:

• Celiac disease
• Cystic fibrosis
• Intestinal or biliary tract disorders (liver, gallbladder, bile ducts)
• People with a portion of their intestine removed

So, what should you look out for with a vitamin K deficiency?

Excessive bleeding is one of the tell-tale signs of a vitamin K deficiency, but it’s important to remember that bleeding can happen in areas besides a cut or wound site.

This bleeding may also be evident if someone:

• Bruises easily
• Has small blood clots underneath their nails
• Bleeds in mucous membranes that line areas inside the body
• Produces dark black, tar-like stool that contains some blood

Although vitamin K is heavily involved in blood clotting, a deficiency of vitamin K can also lead to issues with bone and heart health, such as lowered bone mineral density, slow blood clotting, an increased risk of cardiovascular disease, weak bones, and more.

The Alternative: Vitamin K Supplements

On the other hand, supplementation can also be a great way to ensure you’re meeting your daily intake of vitamin K.

Because the concentration of vitamin K is relatively low in most foods, especially plant-based foods, you’ll either end up eating a ton of leafy green vegetables or go the supplementation route.

Our advice? Make it easy and cover all your nutritional needs in one go with vitamin K supplementation.

With Performance Lab NutriGenesis Multi, you don’t need to stress about how much vitamin K you're consuming and if you're consuming enough nutrients in general to support human health (and by the way, stress actually depletes nutrients).

Multi supplies 100% RDI of 17+ vitamins and minerals for optimal full-body performance. It uses NutriGenesis technology to provide nature-identical vitamins and minerals naturally complexed with cofactors to enhance absorption and bioactivities.

Why play with fire and run the risk of a deficiency when you can pop back Multi for your daily dose?

Plus, you're also getting vitamin D3 combined with vitamin K2 to provide greater support for heart and bone health. A vitamin K supplement seems like the most logical solution to us!