There are several factors that relate to the formation of blood clots, such as blood coagulation factors, the level of physical activity we engage in, the use of certain medications, and even some vitamins, such as vitamin K, which we will discuss further on in this article.
One of the major problems associated with cardiovascular health is the formation of thrombi. A thrombus is a blood clot that forms within a blood vessel and can block blood flow, causing significant tissue damage, tissue destruction, and even the death of the affected tissue, a process known as necrosis.
What is vitamin K?
Vitamin K, also known as phylloquinone (K1) or menaquinone (K2) depending on its chemical form, is a fat-soluble vitamin that is very important for blood clotting, as it is required for the production of several proteins involved in the coagulation cascade, such as clotting factors II, VII, IX and X, as well as anticoagulant proteins including protein C, protein S and protein Z.
The exact requirements for this vitamin are still not fully known, as they vary greatly between individuals, but an adequate intake is estimated to be around 90-120 μg per day. Vitamin K is obtained through the diet from foods such as Swiss chard, parsley, kale, cabbage, spinach and other green vegetables. As it is fat-soluble, its absorption depends heavily on the amount of fat in the diet; a diet higher in fat will promote better absorption of this vitamin.
However, this vitamin is also important for maintaining optimal bone mineral density. This is because vitamin K also regulates the production of a hormone that is crucial for bone health: osteocalcin. Maintaining adequate levels of this vitamin ensures proper osteocalcin homeostasis and therefore supports good bone health. Nevertheless, according to large studies, supplementation does not appear to provide clinical benefits in terms of preventing bone fractures.
Is supplementation the only solution?
So, problem solved, if we have clotting issues, we simply eat more foods rich in vitamin K or take a supplement containing this vitamin, right? The answer is clearly no.
Increasing the intake of this vitamin through foods or supplements is completely contraindicated unless prescribed by a doctor. This is mainly because when a person has coagulation-related problems, they are usually placed on daily medication such as warfarin, which is designed to counteract the action of vitamin K. Therefore, increasing vitamin K intake can reduce the effectiveness of the medication and significantly complicate treatment. In addition, scientific evidence does not show clinically meaningful improvements in studies where this vitamin has been supplemented.
Even today, technology is using multivariable models in an attempt to determine precise dosing based on large datasets, which can currently explain up to 60% of the variability observed.
Does this mean we should stop consuming vitamin K if we have a clotting disorder?
Once again, the answer is no. This is because the pharmacological dose is adjusted to the levels of this vitamin that you usually have in your blood; in short, no changes to diet are recommended.
Other medications can also affect the total amount of vitamin K we typically have, such as antibiotics (which reduce the amount of vitamin K produced by the gut microbiota), bile acid sequestrants (which lower blood cholesterol levels and therefore hinder the transport of this vitamin), or orlistat (which blocks pancreatic lipases, proteins necessary for fat digestion, thereby reducing fat absorption and, consequently, the absorption of this vitamin).
In addition to all these factors, genetics also plays a role. The metabolism of this vitamin partly depends on genetic variants that can influence its function, transport and even its breakdown. These genetic variants can be found in genes such as APOE4, VKORC1, GGCX or CYP4F2.
Finally, it is worth emphasising that vitamin K is very important, as we have seen. However, this does not mean that we should significantly modify its intake or supplement it (unless advised by a doctor), since according to current evidence, this does not translate into meaningful health benefits.
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