Vitamin D3 and K2, a Dynamic Duo for Your Bones
Vitamin D is probably familiar to you, but did you know that this sunshine vitamin is even more powerful when combined with vitamin K? Together, they ensure proper absorption and utilisation of calcium in your body. In this blog, discover how vitamin D3 and K2 complement each other and why you often find them together in supplements.
What is Vitamin D?
Vitamin D plays an important role in several processes in your body. It is a fat-soluble vitamin, which means it is stored in fat tissue and organs such as your liver. This allows your body to build up a reserve for times when you produce less vitamin D, such as in the winter months1.
What Does Vitamin D Do?
Vitamin D helps with:
- The absorption of calcium and phosphorus from food
- The maintenance of strong muscles
- Supporting your immune system
- Maintaining strong teeth
- The production of cells and tissues
Where is Vitamin D Found?
Your body produces vitamin D under the influence of sunlight, but you can also obtain vitamin D from food. Think of oily fish such as salmon, mackerel, and herring. Vitamin D is also found in smaller amounts in meat, eggs, and mushrooms. In autumn and winter, when you see less sunlight, a vitamin D supplement can be a smart choice!
What is the Difference Between Vitamin D2 and D3?
There are two forms of vitamin D:
- D3 (cholecalciferol): produced by your skin under the influence of sunlight and found in animal products.
- D2 (ergocalciferol): found in certain mushrooms and fungi.
Vitamin D3 is better absorbed, which is why you more often see this form in supplements. Want to know more? Read here all about vitamin D.
What is Vitamin K?
Vitamin K is less well-known than vitamin D but is just as important. Vitamin K helps with the deposition of calcium in your bones2 and also ensures proper blood clotting. Vitamin K is produced by the bacteria in our large intestine from about 3 months of age. The amount produced is often not enough to meet our full needs. Therefore, it is important to also obtain vitamin K from food.
Where is Vitamin K Found?
Vitamin K comes in two forms:
- Vitamin K1: mainly found in green leafy vegetables such as spinach and kale. Vitamin K1 is important for blood clotting.
- Vitamin K2: found in fermented foods such as cheese and natto (a Japanese dish of fermented soybeans), and in small amounts in meat and eggs. Vitamin K2 is better absorbed by your body and specifically helps with the transport of calcium to your bones.
Want to know more? Discover here all about vitamin K
Why Vitamin D and K Together?
Vitamin D3 and K2 work together to support your bones. Vitamin D3 helps your body absorb calcium from food, while vitamin K2 ensures it gets to where it is needed: in your bones.
Furthermore, studies suggest3 that this combination may be beneficial for your heart and blood vessels. Vitamin D and K can together help keep your blood vessels flexible. There are also indications that a good balance of these vitamins could contribute to maintaining normal blood pressure.
Why Vitamin D3 and K2 (and Not D2 and K1)?
While there are multiple variants of vitamin D and K, the D3 and K2 combination is the best option. But why choose these forms specifically and not D2 and K1? D3 and K2 are better absorbed by your body than vitamin D2 and K1. For a proper distribution of calcium in the body, vitamin K2 also plays an important role. Vitamin K2 differs from K1 because it not only helps with blood clotting but can also fix calcium in the bones by activating certain proteins in the body. By taking these two together, you ensure better calcium absorption and that the calcium is properly utilised in your body.
At What Dosage of Vitamin D is Vitamin K Important?
When you take a higher dosage of vitamin D3 (25 to 50 micrograms per day or more), it can be wise to also take vitamin K2. Vitamin K2 helps to ensure that the calcium absorbed by D3 gets to the right place: in your bones, not in your blood vessels. This prevents calcification of the blood vessels and supports your bone health4.
Combining Vitamin D and K for Babies
Did you know that these vitamins are also important for babies? From birth, your baby needs 10 micrograms of vitamin D daily for the normal growth and development of bones and teeth. Additionally, vitamin K is crucial, especially during the first 12 weeks. This is because your baby's intestines are "clean" at birth; they have not yet developed the bacteria needed to produce sufficient vitamin K. For children under four years, drops are usually recommended instead of tablets5. Read here more about vitamin D and K for babies.
Good to Know
Vitamin D3 and K2 are often used together in supplements due to their role in the absorption and processing of calcium. D3 supports the absorption of calcium from food, while K2 ensures that calcium is properly processed in the body.
Tip: Vitamin D and K are fat-soluble vitamins, meaning they are better absorbed with a meal that contains healthy fats. So, add some avocado, nuts, or olive oil to your meal. This way, your body benefits optimally from these vitamins!
Sources:
- Voedingscentrum. (n.d.). Vitamin D. Available at: https://www.voedingscentrum.nl/encyclopedie/vitamine-d.aspx
- Voedingscentrum. (n.d.). Vitamin K. Available at: https://www.voedingscentrum.nl/encyclopedie/vitamine-k.aspx
- Van Ballegooijen, A. J. (2017). Vitamin D and K work together for strong bones and clean vessels. Nutrition Magazine, 4, 16-19. Available at: http://edepot.wur.nl/440347
- Van Ballegooijen, A. J., & Beulens, J. W. (2017). The role of vitamin K status in cardiovascular health: evidence from observational and clinical studies. Current nutrition reports, 6, 197-205.
- Voedingscentrum. (n.d.). Vitamins for your baby alongside bottle feeding. Available at https://www.voedingscentrum.nl/nl/zwanger-en-kind/borstvoeding-en-flesvoeding/flesvoeding-geven/vitamines-voor-je-baby-naast-flesvoeding.aspx
