MK-4? MK-7? | Which one is the best form for Vitamin K2?
There are a few different forms of Vitamin K2, and they can be divided into subtypes. They are each abbreviated MK-number, where the number gets bigger as the tail gets longer.
To give an example, MK-4 represents short-chain vitamin K2, and MK-7 represents long-chain Vitamin K2.
Not all Vitamin K2s are equally well absorbed
When taking Vitamin K2, we need to make sure that our bodies can absorb and use it, making sure to activate two proteins: Osteocalcin and MGP (Matrix Gla Protein).
And out of all vitamin K2 forms, Vitamin K2 MK-7 has proven to be absorbed into the body most efficiently and has shown the most excellent bioavailability.
MK-4’s half-life is very short and easily decomposed in the body, meaning that it is effective when the intake amount and the number of intakes are high enough. According to a research study, the bioavailability of MK-4 was found to not reflect an increased serum concentration after administration (Halder et al., 2019). Such a short half-life and poor bioavailability of MK-4 make MK-7 stands out in terms of efficacy and efficiency.
MK- 7 matters the most
MK-7 does have an increase in the blood level concentrations and those levels are increased for several days. (Halder et al., 2019)
It’s because the portion of MK-7 that reaches our body stays active much longer before breaking down, which means that MK-7 has the highest bioavailability among vitamin K2.
MK-4(K2)
MK-7(K2)
What about MK-9 or MK-#?
If MK-7 is better than MK-4, what about MK-9? Or even above? Would it be better than MK-7 or MK-4?
MK-9 stays in the body for a long time since it has a very long half-time. But it is found to be absorbed poorly compared to MK-7.
Final Thoughts
Many research studies have proved MK-7 is best absorbed into the body and stays long. Finally, the function in the human body appears that MK-7 has all of the functions of MK-4, with a longer half-life (Schwalfenberg, 2017).
Therefore, the conclusion can be summarized simply: Vitamin K2 as MK-7 is the best form of Vitamin K2!
Reference |
Halder M, Petsophonsakul P, Akbulut AC, Pavlic A, Bohan F, Anderson E, Maresz K, Kramann R, Schurgers L. Vitamin K: Double Bonds beyond Coagulation Insights into Differences between Vitamin K1 and K2 in Health and Disease. Int J Mol Sci. 2019 Feb 19;20(4):896. doi: 10.3390/ijms20040896. PMID: 30791399; PMCID: PMC6413124.
Schwalfenberg GK. Vitamins K1 and K2: The Emerging Group of Vitamins Required for Human Health. J Nutr Metab. 2017;2017:6254836. doi: 10.1155/2017/6254836. Epub 2017 Jun 18. PMID: 28698808; PMCID: PMC5494092.