Does Vitamin K2 Increase Testosterone?

  • There is evidence to suggest Vitamin K2 raises T levels
  • However most of the available studies have been conducted on animals
  • The ideal daily dosage is no more than 120mcg

Vitamin K is probably the least known of all vitamins. It is a fat-soluble nutrient essential for coagulation. The “K” is derived from the German word Coagulant. There are several thousand forms of Vitamin K, but the two main forms are Vitamin K1 or phylloquinone and K2 or menaquinone.

While Vitamin K1 is present in almost all green leafy vegetables, Vitamin K2 is found in liver, egg yolks, red meat, and butter. We only require a small amount of this vitamin to meet the recommended daily dosage but is estimated that nearly 80 percent of the population does not get enough of it.

Health benefits of Vitamin K2

Until recently, Vitamin K1 got all the attention as far as the health benefits of Vitamin K were concerned. This was probably because we get over ten times more the amount of Vitamin K1 in our diet compared to K2. It was believed that the body would convert K1 into K2 as needed. However, latest findings have revealed that we need to source K2 separately to get the many health benefits it offers.

Research has shown that Vitamin K2 can significantly lower the risk of cardiovascular disease by helping the removal of calcium deposits from arteries. Another research has shown that Vitamin K2 supplementation can reduce the risk of prostate cancer by over 30 percent. In both the researchers, Vitamin K1 was found to have no effect.

Vitamin K2 is also known as a potent testosterone booster. That is what we are going to focus on here. Let us check out how Vitamin K2 affects testosterone levels, what the research says and how we can get enough of it.

How Vitamin K2 affects testosterone levels

Vitamin K2 is believed to help boost testosterone levels by following mechanisms:

  • Influencing testosterone synthesis: Vitamin K2 inhibits inflammation and regulates certain genes, thus protecting testosterone from potential killers.
  • Vitamin K deficiency can cause downregulation of an enzyme critical to T-synthesis. By maintaining adequate Vitamin K levels, higher T-levels can be maintained.
  • By potentially interacting with sex hormone binding globulin (SHBG).

Research on Vitamin K2’s testosterone boosting effects

Some animal studies show a strong correlation between Vitamin K and testosterone levels. Here is what these studies found:

Dietary vitamin K alleviates the reduction in testosterone production induced by lipopolysaccharide administration in rat testis

In this study, rats were divided into two groups. One group was fed a Vitamin K free diet, and the other was the control group. After 35 days, both the groups were administered lipopolysaccharides (LPS) to induce inflammation. Researchers found that:

  • Neither of the groups showed Vitamin K deficiency.
  • The rats that received Vitamin K free diet had lower levels of Vitamin K in their testis
  • Vitamin K free group had lower testosterone levels compared to the control group
  • Luteinizing hormone was unaffected by both diet and LPS administration

It was concluded that dietary Vitamin K affects the amount of Vitamin K in the testis, and also prevents testosterone depletion caused by inflammation.

Menaquinone-4 enhances testosterone production in rats and testis-derived tumor cells

In this study, eight week old male Wistar rats were fed a diet supplemented with 75 mg/kg menaquinone-4, which is one of the main Kvitamins present in the testis. After five weeks of supplementation, it was observed that:

  • Testosterone levels in the testes and plasma of MK-4-fed rats were significantly increased compared to the control group
  • No differences in plasma luteinizing hormone (LH) level
  • Secreted testosterone levels were increased by MK-4, but not by vitamin K1

It was concluded that MK-4 stimulates testosterone production in rats and testis-derived tumor cells via activation of protein kinase A (PKA).

Supplementing with Vitamin K2

The recommended daily dosage of Vitamin K2 is 120 mcg. A dosage above 45,000 mcg becomes toxic. Most supplements contain 100-150 mcg Vitamin K2. Vitamin K2 supplements are available in two forms: MK-4 and MK-7. MK-4 is more commonly used in supplements as it acts independently of the Vitamin K cycle in the body. MK-7 is more bioavailable compared to MK-4 and works within the vitamin K cycle. However, it stays in the body for a longer time, while MK-4 stays in for only 8 hours. For this reason, some prefer MK-7 over MK-4.

Possible Side Effects of Vitamin K2

Oral Vitamin K2 supplements are seldom toxic. Both menaquinone and phylloquinone are considered safe. However, Vitamin K3 or menadione is known to be toxic and should be avoided.


Vitamin K2 does seem to work as a testosterone booster. However, it has still not been tested on humans. It has only been tested on rats and that too with high doses. The same quantity if given to a human can prove toxic. We can draw definitive conclusions only after human studies are conducted.