It may come as a shock to anyone who watches late-night commercials, but testosterone interests medical science for far more reasons than “feeling younger” or “performing better” in the bedroom. In fact, testosterone plays a role in everything from muscle-bone tissue binding to, as we’ll discuss, blood clotting.
All of which brings us to a discussion of a rarely-talked about nutrient: Vitamin K. I’ve been researching some of the more alternative testosterone supplement ingredients, and a few weeks ago I felt compelled to shed some light on how another overlooked nutrient, Vitamin D, is actually quite effective at stimulating testosterone increases. Now, I’ll explain how Vitamin K can be another secret weapon of anyone looking for natural testosterone answers.
Key Findings
✲ Vitamin K has been conclusively shown to correlate to testosterone production in laboratory animals.
✲ These animals have the exact same testosterone/Vitamin K mechanism as humans.
✲ Most human studies of Vitamin K revolve around a form of testosterone called sex hormone binding globulin (SHBG), wherein Vitamin K plays an essential role.
✲ Another study finds that Vitamin K can improve Vitamin D results in active men.
A Brief Overview of SHBG and Vitamin K
Most people researching testosterone are aware of the difference between free testosterone and blood testosterone. The main difference is that most testosterone in the blood is “bound” to blood cells, becoming SHBG. These cells can be broken up if the body is in dire need of testosterone, but otherwise are called upon during blood clotting.
How SHBG and blood clotting are related has only been recently explored, through the mechanism of something called protein S. Conventional wisdom has been that Vitamin K is essential for blood clotting, and that SHBG plays a role, as well. This all sets the stage for the studies we’ll look at, next, where scientists have looked into whether Vitamin K’s role in blood clotting may also relate to SHBG (testosterone).
Human Studies
First we’ll look at two important in vitro studies that explored the relationship between Vitamin K, protein S, and testosterone.
The first study was conducted a while ago, but has become foundational to the understanding of Vitamin K. In it, researchers determined that protein S is Vitamin K dependent (cannot exist without it), and that it is present in the Leydig cells of the testis (which also produce testosterone).
Secondly, and also proving to be fundamental to all future research, protein S has been shown to have “considerable” similarity to SHBG.
The rest of the studies have built on that understanding to conduct trials experimenting with adjusting Vitamin K levels and screening for SHBG and testosterone.
Animal Studies
Research on Vitamin K and animal testosterone goes back for a couple of decades; I won’t cite the half-dozen or so studies, because that would become tedious to read. Instead, I’ll highlight the most recent and rigorous trials.
In one study, researchers looked to determine if testosterone production could be stimulated with Vitamin K in animals that had been given warfarin (an anticoagulant). Scientists were interested because it has appeared that warfarin thins the blood through breaking up small clots that form from blood cells flowing through the body–but to the point that excess bleeding occurs. Scientists have then hypothesized that Vitamin K can boost testosterone, forming more SHBG, and preventing excess bleeding.
In short, the study was a success. Testosterone levels in all the subjects significantly increased, including in the warfarin subjects. Some of the researchers (on a previous team) even found that Vitamin K was specifically able to promote testosterone production in the testes of these animals.
These results, and the many other studies conducted, have been strong enough to be quoted by other Vitamin K researchers as conclusive that Vitamin K does stimulate testosterone production.
Back to the Humans
Taking the entire literature into account, scientists are now simply studying protein S, SHBG, and another protein called Androgen Binding Protein, which is the primary transporter of testosterone in the body. Research indicates that all of these mechanisms are Vitamin K dependent.
These determinations have led to longitudinal studies of peripubertal children, where Vitamin K levels are directly linked to testosterone levels.
And lastly we see a study of Vitamin D and Vitamin K in active adults. This is a very recent study that requires follow-up research, but it indicates that Vitamin K may be an important helper-vitamin in the body's use of Vitamin D for testosterone production.
Final Thoughts
This article has taken us down the testosterone-path-less-traveled. Most people associate the male sex hormone with bulging muscles and youthful energy, but it also plays a role in other body function, like blood clotting.
Because Vitamin K is so pivotal for blood clotting, a potentially life-saving mechanism, almost all Vitamin K research is in that field. That research has yielded proof of testosterone production–just not the kind most people are looking for out of “male enhancement” products. Instead, Vitamin K significantly increases protein S related testosterone–in the form of sex hormone binding globule. An essential, if not necessarily wildly popular, testosterone function in the body.