How to Choose the Best Vitamin K2? What to Look for in a Supplement

Vitamin K2 is a compound that was little known a few years ago, but today it is considered one of the key elements in the prevention of heart, bone, and dental health problems. However, not all K2 is the same – differences in form, source, and supplement quality can have a major impact on its effectiveness. In this article, we explain how to choose the best vitamin K2 supplement, what to look for when buying it, and why combining it with vitamin D3 is the gold standard of modern supplementation.

What Is Vitamin K2 and Why Is It So Important?

Vitamin K2 (menaquinone) belongs to the group of fat-soluble vitamins. Its main role is to activate proteins responsible for calcium transport and utilization in the body – primarily osteocalcin and Matrix Gla Protein (MGP). Thanks to this, vitamin K2 supports bone health and prevents calcium buildup in blood vessels, which helps protect the cardiovascular system.

“Studies show that vitamin K2 supplementation (especially in the MK-7 form) may reduce the risk of osteoporotic fractures and vascular calcification by up to 50%.”

MK-4 or MK-7 – Which Form of Vitamin K2 Is Better?

Vitamin K2 exists in various chemical forms – most commonly as MK-4 and MK-7. These are the two forms most often found in supplements, but they differ significantly in terms of stability and bioavailability.

• MK-4 – naturally found in meat, egg yolks, and butter. However, it has a very short half-life in the body (about 1–2 hours), so it needs to be taken more frequently.
• MK-7 – produced through the fermentation of soy or chickpeas (for example, in the traditional Japanese food natto). It has a long duration of action (up to 72 hours), high bioavailability, and excellent stability, making it the best choice for supplementation.

Therefore, if you value effectiveness and convenience, choose a supplement containing vitamin K2 in the MK-7 form derived from a natural source – preferably from natto fermentation.

Natural vs Synthetic Sources of Vitamin K2

There are two main types of vitamin K2 available on the market:

• Natural Vitamin K2 (MK-7 from natto) – obtained through the fermentation of soy or chickpeas by the bacteria Bacillus subtilis natto. It has the highest bioavailability and is well tolerated by the body.
• Synthetic Vitamin K2 – produced chemically, often in the MK-4 form. Although it works similarly, it has a shorter active time and may be less stable.

When choosing a supplement, it’s worth paying attention to the source – natural MK-7 from natto guarantees higher quality and better absorption.

What Else Should You Pay Attention to When Buying Vitamin K2?

In addition to the form and source of K2, several other factors often determine the quality of a supplement:

• Purity of composition – choose products without artificial colorings, preservatives, palm oil, or unnecessary fillers.
• Capsule form – plant-based (vegan) capsules are a better option for those who value natural ingredients and high tolerance.
• Combination with vitamin D3 – K2 works synergistically with D3, together regulating calcium-phosphorus balance. This is why the best products combine these two vitamins in one capsule.
• Dosage and stability – make sure the supplement provides a stable dose of K2 (usually 100 µg MK-7 per day) and is stored in a tightly sealed, dark container protected from light.

Vitamin K2 and D3 – Why This Duo Matters

Vitamin D3 increases calcium absorption from the digestive tract, but it’s the presence of K2 that ensures calcium goes where it’s needed – to the bones and teeth, not the arteries. A lack of K2 during D3 supplementation may lead to unwanted effects, such as calcium deposits in the vessels.

Therefore, the best solution is to choose a supplement combining vitamin D3 with K2 (MK-7) in optimal proportions. An example of such a product is UNUVI D3 + K2 – a clean formula based on natural vitamin K2 MK-7 and vitamin D3, without unnecessary additives.

Summary: How to Choose the Best Vitamin K2

• Choose the MK-7 form – preferably naturally derived from natto fermentation.
• Avoid supplements with synthetic MK-4, which has a short active time.
• Pay attention to purity of composition and absence of artificial additives.
• Opt for a K2 + D3 combination for synergistic effects.
• Check the origin – natural forms are more stable and bioavailable.

Making an informed choice of a vitamin K2 supplement is an investment in strong bones, healthy teeth, and a well-functioning heart. Choose quality, natural origin, and a carefully designed formula – and your body will thank you with vitality and long-term health.