How to combine vitamin D and vitamin K properly

Q: Why should you take vitamin D with K2?

Vitamin D3 ensures that your body absorbs calcium better. K2 then directs this calcium into the bones and prevents it from being deposited in the blood vessels.

Q: Why should vitamin D3 always be taken together with vitamin K2?

Because although D3 increases calcium, without K2 there is no mechanism to incorporate it into the bones. The interaction makes it sensible to combine the two.

Q: Why should vitamin D3 and K2 not be taken together?

There is no real reason to separate them. Some say it is not absolutely necessary to take them at the same time. But there is no disadvantage to taking them together. On the contrary, it is usually more practical.

Q: When should vitamin D3 K2 be taken (time of day)?

Preferably in the morning or at lunchtime with a meal containing fat. In the evening, it can disturb sleep in some people.

Q: Can vitamin D3 and K2 be taken every day?

Yes, this is actually common practice. Some people take higher doses of D3 weekly, but daily intake ensures more consistent levels.

Q: What are vitamin D3 K2 drops good for?

They stabilize vitamin D levels and support bones, teeth, muscles, and the immune system. K2 also reduces the risk of calcium deposits in the blood vessels.

Q: What is the recommended dosage of K2 with vitamin D3?

A common recommendation is to take about 10 to 20 micrograms of K2 (MK-7) per 1000 IU of vitamin D3. If you are taking very high doses of vitamin D, you should also increase your K2 intake.

Q: What happens if you take too much vitamin D3 and K2?

An overdose of vitamin D3 can lead to too much calcium in the blood, which can cause nausea, kidney problems, or calcification. It is difficult to overdose on K2 because the body excretes any excess. It only becomes dangerous in extremely high amounts over a long period of time.

Q: Is the combination of vitamin D3 and vitamin K2 safe?

Yes, it is safe for healthy people in normal doses. However, anyone taking anticoagulants should only take K2 after consulting their doctor.

Prof. Dr. Elmar Wienecke

24 лют. 2022 р.

Reading time: 3 minutes

How to combine vitamin D and vitamin K properly

Recent studies clearly demonstrate that vitamin D3 and vitamin K2 are essential to good health. Deficiencies in both these vitamins are extremely common, which is why more and more people are taking vitamins D3 and K2 as a daily dietary supplement.

It's very important to know that if you take vitamin D3 regularly over a long period, you definitely need to take vitamin K2 as well. This raises the question of how these two key vitamins should best be combined in order to promote health and vitality.

Topics in this article:

Why You Need Both Vitamin D3 and Vitamin K2
The Synergistic Relationship
EFSA nutrient intake reference values for vitamin D and vitamin K
The Science Behind Vitamin K2

Why You Need Both Vitamin D3 and Vitamin K2
The Synergistic Relationship
EFSA nutrient intake reference values for vitamin D and vitamin K
The Science Behind Vitamin K2

Why You Need Both Vitamin D3 and Vitamin K2

Vitamin D3 helps your body absorb calcium from the diet. But without enough vitamin K2, that calcium may not be directed where it’s needed such as your bones and teeth and can instead end up in soft tissues like arteries, potentially leading to calcification and arteriosclerosis.

Vitamin K2 activates specific proteins such as osteocalcin and matrix Gla-protein (MGP) that:

Direct calcium into bones and teeth
Prevent calcium buildup in arteries and soft tissues

In short: Vitamin D3 increases calcium availability, while vitamin K2 ensures it’s used properly.

The Synergistic Relationship

Taking vitamin D increases the body’s production of vitamin K2-dependent proteins. But without enough K2, these proteins remain inactive, and calcium can go to the wrong places. Together, D3 and K2:

Strengthen bones
Support heart and vascular health
Reduce the risk of osteoporosis and arteriosclerosis

EFSA nutrient intake reference values for vitamin D and vitamin K

The European Food Safety Authority (EFSA) has developed recommendations for adequate nutrient intake.

These nutrient intake reference values are intended for healthy people and should not be understood as direct recommendations for individuals. Individual requirements for vitamin D and vitamin K can vary considerably depending on personal circumstances.

If in doubt, consult your doctor or a specialist to find out your individual requirements.

Reference values for vitamin K according to EFSA

Target group	Adequate intake
Adults aged 18 and over, both sexes	70 µg / day
Children aged 15 to 17, both sexes	65 µg / day
Children aged 7 to 10, both sexes	30 µg / day
Children aged 4 to 6 years, both sexes	20 µg / day
Children aged 1 to 3 years, both sexes	12 µg/day

These estimated values indicate the average intake of the nutrient that is considered sufficient based on observations or experimental studies.

Source: EFSA DRV Finder

Reference values for vitamin D according to EFSA

Target group	Adequate intake
Adults aged 18 and over, both sexes	15 µg / day
Children up to 17 years of age, both sexes	15 µg / day

These estimated values indicate the average intake of the nutrient that is considered sufficient based on observations or experimental studies.

Source: EFSA DRV Finder

The Science Behind Vitamin K2

Vitamin K2 activates two vital proteins:

Osteocalcin – helps bind calcium to the bone matrix
Matrix Gla Protein (MGP) – prevents calcium from depositing in arteries

Without vitamin K2, calcium can accumulate in the wrong places—even when taking vitamin D3. This imbalance can contribute to:

Arterial calcification
Weakened bones
Higher cardiovascular risk

Conclusion

Vitamin D3 and vitamin K2 are a powerful team that work best when taken together. If you’re supplementing with vitamin D3, don’t overlook K2. The right balance supports your bones, heart, and overall health while avoiding the risks of misplaced calcium.

Frequently Asked Questions About Combine Vitamin D and Vitamin K

Which vitamin D3 K2 is the best?

There is no “best” product for everyone. It is important that D3 comes from a high-quality source, preferably cholecalciferol. K2 should be in the form of MK-7 all-trans because it is the most stable. Drops are practical because you can dose them precisely, while capsules are more convenient for on the go. Also, make sure that the supplement is dissolved in oil, as D3 is fat-soluble.

Why should you take vitamin D with K2?

Why should vitamin D3 always be taken together with vitamin K2?

Why should vitamin D3 and K2 not be taken together?

When should vitamin D3 K2 be taken (time of day)?

Can vitamin D3 and K2 be taken every day?

What are vitamin D3 K2 drops good for?

What is the recommended dosage of K2 with vitamin D3?

What happens if you take too much vitamin D3 and K2?

Is the combination of vitamin D3 and vitamin K2 safe?

When is the best time to take vitamin D and vitamin K?

Can you get enough vitamin D and vitamin K from food?

Should you have a blood test before taking vitamin D and K2?

What should you look for in a vitamin D3-K2 supplement?

Which nutrients additionally support the effect of vitamin D and vitamin K?

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