Do you need Calcium, or something else

In fact, we don't need so much Calcium, how much we need other two things that are closely related how well we bound Calcium in our bones and not deposit it where we definitely don't need it - like in our kidney or inside of the arteries. That is a very bad place for the C to go, and nobody wants it there - but, it happens if it doesn't get bounded.
And it happens also to the people who lead extra healthy life-styles and believe they are following the best practices.
The two things that are needed for the C to go to the right place, and not to wreck havoc, are K2 and D3.

Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D₃ and vitamin D₂.

I heard for this D vitamin and how we soak it somehow from the sunlight ( skin is creating it), but I didn't know there was D2 and D3. So, one of them is the one we need for Calcium to do it's job.
You can easily purchase D3 in almost any store as a food supplement. Now the hard part.

Vitamin K2 or menaquinone is both a tissue and bacterial product (derived from vitamin K1 in both cases) and is usually found in animal products or fermented foods.

Sources for this vitamin in food sound so easily to be acquired - like meat, dairy, fish, patte, eggs... you name it. But! While D3 is really cheap, K2 is horribly expensive.
So, how does something that is easily acquired through the food is so horribly expensive while searched in the store??

It is also said that more than half of the population lacking in these two! It means that either our food is getting increasingly poor in nutrients or we simply can't get enough of it from the natural sources.

Vitamin D3 and vitamin K2 ensure that calcium is absorbed easily and reaches the bone mass, while preventing arterial calcification. Helping to keep your heart and bones healthy. Separately, K2 regulates normal blood clotting, whilst D3 supports a healthy immune system and supports muscle function.

It really doesn't make any sense, but I will investigate further on.