Everywhere there is the combination of vitamin D and vitamin K2. So it seems obvious that the two complement each other, right?
First of all, short: K is short for coagulation, or simply blood clotting. That sounds vital for survival. Vitamin K2 is also known as menaquinone and is produced from vitamin K1 from bacteria such as those in our gut.
You get vitamin D through the sun and it plays a crucial role in bone health.
Now it is said that vitamin D in combination with K2 is particularly good for the bones. We are sticking to what is involved in this process. But first, let’s look at what vitamin K2 itself can do.
Vitamin K2 – and beyond?
Menaquinone – or vitamin K2 – is one of the fat-soluble K vitamins. K stands for coagulation (blood clotting) because it acts indirectly on them. If you look into the respective regulation of the EU Commission, you will read that the EU also confirms the effect. K vitamins contribute to normal blood clotting and maintenance of normal bone structure .
However, it has not been entered that it also contributes to the protection against atherosclerosis, as the data situation is too weak here. Although there have been initial indications since 2004 that vitamin K can contribute to the reduction of “vascular calcification”, this study has worked too inaccurately. In 2020, researchers showed in a meta-study, i.e. in a study that evaluated several studies, that vitamin K2 does not work against atherosclerosis or improves arterial stiffness.
When it comes to dosage, as is usual with most nutrients, there is not quite agreement on what the right amount is. While the European Food Safety Authority (EFSA) assumes 1 μg per kg body weight of vitamin K , the Federal Institute for Risk Assessment for the DACH region (Germany, Austria and Switzerland) has similar values (about 1 μg of vitamin K per kg of weight), but distinguishes in detail between vitamin K1 and K2. They set the daily recommended dose for vitamin K2 by means of dietary supplements to a maximum of 25 μg.
So high doses are not dangerous for healthy people. However, some people are hypersensitive and this can lead to side effects. In general, however, there are no overdose symptoms in healthy people. EFSA therefore does not specify a maximum amount here.
In any case, you need vitamin K for proteins that are necessary for blood clotting or for blood plasma . Likewise, your kidney and bones need enough vitamin K. Research is also discussing whether vitamin K also has a positive influence on cardiovascular diseases.
But then you should definitely do without vitamin K2
There are groups of people who should definitely avoid vitamin K2 . Those who need to take anticoagulant drugs : in particular, coumarin-based. Vitamin K2 can interfere with the effect, which can lead to massive problems. Here you have to be careful.
But now to the original question:
What does science say about vitamin D and K2?
There are theoretical considerations that there are possible interacting effects between the two vitamins. They say that these effects support bone health particularly well. However, there are currently no sufficient studies to prove this.
Something similar can be said about the commonly referred to “vascular calcification”, which according to statements should be triggered by too high vitamin D dosages. Vitamin K is supposed to protect against this, for which there is evidence, but this is also not sufficiently proven.
In the case of osteoporosis , there is exactly one right answer: Your doctor can tell you exactly what makes sense.
The fact that the two vitamins complement each other well in terms of effect cannot be denied. After all, a sufficient supply of vitamin D is also necessary for normal bone stability. That is why the combination of these two vitamins is also gladly offered.
However, the following remains central: As with all nutrients and supplements , the rule of thumb is to first clarify – via a blood test – what the exact deficiency in the body is. Then you can balance them specifically and precisely and live healthy.
Only vitamin D with K2? Can work, but doesn’t have to.
Often you read that the two only work optimally in a team. From a purely scientific point of view, we do not yet know for sure that this is the case.
However, there is circumstantial evidence and in some cases this is also possible. In general, however, this is difficult to say and can also lead to problems – even if vitamin K does not have prescribed maximum levels.
Overall, it should be said again that a visit to the family doctor is recommended. After a quick test, you know exactly what you are missing and can take targeted and correctly dosed action against the deficiencies by means of dietary supplements. This keeps your body healthy.