I will discuss these two vitamins in one chapter, as their functions are partially combined.
Vitamin K2 is an enigma. It is perhaps the only nutrient whose supplementation has shown a powerful health-promoting effect, and which is simply not found in food. Some micro-quantities are found in a few foods, a little can be synthesized by our intestinal flora and some cells, but these are all very minute values compared to what has been used successfully in studies.
How…? Nature does not make such mistakes. After all, natural selection should have occurred long ago, those of us who produce more of it in the body should survive. Or those whose bodies don’t need the vitamin, can do without it. That’s what happened (and continues to happen, as its levels have only declined in recent centuries) with D3. Maybe it’s simply a matter of some source that has recently disappeared from our menus? I’ve heard of studies showing its presence in insects. Other scientists say it may have been produced in the cecum, but our species would have recently lost that ability. Nevertheless, here natural selection should already be at work.
In other words, we are dealing with something that had no right to happen. The most obvious solution is… an error in research. That is, the effects of vitamin K2 supplementation may not be so good after all.
What did the initial studies show? The benefits of using K2 were so great as to be unbelievable. It looked like a situation from some fairy tale or S-F movie. For how else to refer to the fact that in a group at high risk of liver cancer, those who received it had a risk of the disease lowered almost tenfold? In another study, the probability of bone fracture dropped by about 90% compared to the control group.
What did it turn out to be? The study in which vitamin K2 reduced the risk of fractures was withdrawn after the author was proven to have falsified the result. In fact, supplementation improved bone health, but this was true for all forms, including K1, present in the green parts of plants. Also, the regular form of K1 reduced the risk of cancer fourfold, although with such a small group of patients this may have been a coincidence:
https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0050196
The reduction in cancer risk appears to be real, although not as dramatic as in the case of liver cancer:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5958717/
Anyway, several more studies, already conducted more rigorously, have shown that even for liver cancer this vitamin has little, if any, effect.
There are a few studies in which those with the highest intake had a reduced risk of cardiovascular disease, but here it must be remembered that this vitamin naturally occurs mainly in those foods that contain other substances that protect against these diseases. Nevertheless, a preliminary clinical trial has shown some protective effect:
https://www.ncbi.nlm.nih.gov/pubmed/26176325
The effects were not stunning, the progression of the disease was slowed down by a mere 5% or so, but it was detectable in studies. Epidemiological studies suggest that regular vitamin K1 may also have this effect.
In conclusion, the effects of supplementation are not striking, which may explain the paradox I wrote about at the beginning. There was no natural selection of people whose body does not produce vitamin K2, because its role is relatively small. Slowing the atherosclerotic process by 5% will have virtually no effect on the chance of passing on one’s genes. The reduction in cancer risk in studies determining intake from the daily diet was on the order of several percent, with the results possibly falsified by the presence of conjugated linoleic acid, which has anti-cancer effects, in products that contain vitamin K2.
Information that only the MK7 form works and MK4 does not, is mainly spread by people who sell the MK7 form. All indications are that these forms are slightly different in action and complement each other. I would suggest a supplement that contains them both.
One Japanese researcher on the subject wrote that he wouldn’t take D3 if he couldn’t supplement K2 at the same time. As he put it, D3 makes calcium absorbed and also built into our body structures, but it’s K2 that makes the body “know” where to put it away. But that’s just him talking, unsupported by studies that have shown this.
We obtain D3 mainly from the sun. Here we can clearly see natural selection – under its influence whites produce several times more of this vitamin compared to black people. Recently, however, sedentary, office-based jobs have emerged, compulsory schooling has appeared, and, to make matters worse, we have begun to use creams with UV filters, completely blocking the skin’s ability to synthesize. As a result, entire populations are suffering from deficiency.
Even before clothing, sitting all day at work or school and traveling in closed cars became so fashionable (or perhaps necessary), there were problems associated with its deficiency, but not enough to lead to the extinction of weaker individuals and clear natural selection. Arguably, a white living in my country, working all day in the field until the last day of autumn and from the first day of spring would benefit only slightly from supplementation, perhaps even none at all, or would even lose out.
However, since almost no one works that way, we have massive shortages. However, it’s hard to get concrete information about their effects on health, as there is a lack of clinical trials that used high enough doses of the supplement long enough. Initial studies suggested a very high cancer-protective effect, but subsequent, more thorough studies have not confirmed this:
https://healthytreatment.org/2022/01/28/vitamin-d3-and-cancer/
The exception is melanoma, in this case association with deficiency seems to be very high.
Something that is quite rarely mentioned, but is very important: Excess D3 is quite severely harmful. Of course, cases of typical poisoning are very rare, it’s almost impossible to get acute symptoms caused by excess, but studies quite clearly show that the graph of the risk of death depending on the concentration of D3 in the blood resembles a parabola.
This means that people on both sides of the extremes are most likely to get sick and die, those with very low concentrations, but also those with very high concentrations. The level of the D(25)OH metabolite should probably be around 30 ng/ml, an increased risk of death has been associated with both values below 20 and above 40 (corresponding to a 50-100 nmol/l). The study also shows that deficiency is much more dangerous than excess. The risk of death increases twice as fast with a decrease in levels as with an increase.
In other words, by using very high doses of the supplement you are probably not only not improving your health, but actually shortening your life. Of course, it is very hard to determine the optimal dose here, but I personally would not exceed 2-4 thousand units in winter (depending on body weight), and 500-1000 units during periods when there is little contact with the sun in summer. Perhaps, but only perhaps, simultaneous K2 supplementation will push the “safe limit” a little higher and you can reap the benefits of blood concentrations above 30 ng/ml, but this is just a hypothesis, the facts are as I described.
Personally, I advise against testing its level, because first of all it is very expensive, secondly, the level changes from month to month, in order to test, for example, the effectiveness of supplementation, you need to do it four or even five times a year, which is already associated with a very serious financial and time burden. So what if I take a measurement today, if in a month’s time I won’t know anymore if, for example, the levels have dropped due to lack of sunlight, or if I have taken too many supplements?
Supplementation is associated with a decrease in magnesium levels, which are used to activate the vitamin, so you should take this element in parallel as well, at least at first. If someone has low levels in the blood and can’t raise for unexplained reasons, it’s possible that he has too low cholesterol, which sometimes happens to health fanatics. In addition, in the first stage of supplementation, one should also take vitamin A, but not in the form of provitamin (i.e. carotene), but ordinary retinol, available at the pharmacy as an ordinary vitamin A supplement.