How to combine vitamin D and vitamin K properly
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
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.
Recommended products: