Vitamin D has long been heralded (or believed) to be a potent supplement that could pose numerous health benefits. One of those benefits is to assist the body with the production of testosterone.
While there have been many testosterone boosting products that have professed to the benefits of Vitamin D, there have also been numerous questions regarding this vital nutrient and its ability to benefit older males who have noticed a decrease in energy levels, focus, strength, stamina, and even sexual drive; all side effects of low testosterone.
The General Importance of Vitamin D on the Body
Growing up, many of us were told about the importance of getting plenty of Vitamin D in our daily diet. Most children are reminded to drink their milk because it contains a significant amount of this vital nutrient. So what is the importance of Vitamin D for the average individual?
Essentially, Vitamin D is responsible for encouraging strong, healthy bones as well as ensuring that muscles, including the heart and brain, work the way they are supposed to. It is also important in helping the body to fight infection.
The Changing Nature of Vitamin D
There are two essential ways that a person’s body gets Vitamin D. The first is through diet. The second is through the sun’s ultraviolet radiation. In both cases, this nutrient must undergo numerous changes within the body before it’s ready to be utilized properly.
Vitamin D is used by the body to regulate the level of calcium in the system, including blood, organs, and bones, and it helps cells throughout the body to communicate with one another properly.
The Connection between Vitamin D and Testosterone Levels
For many years, it has been believed that testosterone production in the body is connected to the level of Vitamin D in the system. For this reason, many different testosterone boosting supplements have included Vitamin D as one of their primary nutrients.
As men age, they experience a decrease in the levels of testosterone in their body naturally. Once a man reaches the age of 25, he will begin to experience a decline in the production of this male hormone. Vitamin D consumption is also commonly associated with a natural process of aging; men spend less time in the direct sunlight, consume less milk and therefore Vitamin D, and so on.
Numerous studies have been conducted in recent years to determine the impact that Vitamin D actually has on the body. The results of several are highlighted here.
Conducted by Pilz, Frisch, et al. at the University of Graz in Austria, the team focused on the finding direct evidence linking supplementation of Vitamin D with an increase in testosterone levels.
The study consisted of 54 healthy overweight men who consumed 83 micrograms of Vitamin D daily for 1 full year. It was a randomized, placebo controlled study and found that this nutrient supplement actually did have a ‘significant increase in total testosterone levels.’ The increase found to be approximately 25% among the control group in the study.
The study further determined that bioactive testosterone levels increased by 20% and free testosterone levels increased by 20%. The conclusion that the team found was that Vitamin D might increase levels of testosterone, but due to the fact that the study focused on healthy but overweight men, they couldn’t determine whether these findings were isolated to this population.
(Read more about this study at Thieme Hormone and Metabolic Research.)
The second study to focus on was conducted at the University of Utah in Salt Lake City, Utah by Hammond, Meikle, et al. These researchers were testing the impact that 25-hydroxy-vitamin D would have on men with regard to seminal potency and hormonal parameters.
170 healthy men took part in this study and did not receive any direct Vitamin D supplementation. The researchers were focused on measuring testosterone levels and hormonal parameters while also measuring the levels of vitamin D that each man was consuming or had in his system.
The results did not find any direct correlation between Vitamin D levels and testosterone levels, therefore no direct conclusions associated with these two were drawn.
(Read more about this study at Asian Journal of Andrology.)
Conducted by the University of Tromso in Norway, researchers Jorde, Grimnes, at al. focused on determining if daily supplementation of Vitamin D was directly correlated to an increase in testosterone levels in men. 893 men took part in this study and were given 20,000 to 40,000 IU (International Units) of Vitamin D for 6 to 12 months for the control group.
This was measured against the group using a placebo. The researchers determined that no significant effect was found with regard to serum total or free testosterone levels in the control group.
(Read more about this study at NCBI.)
One study listed here found a direct link between increased testosterone levels, including free testosterone and Vitamin D supplements while another found no correlation between the two. The study that found a correlation was conducted with healthy yet overweight men, which could have impacted their findings.
According to research, Vitamin D by itself may not have the intended impact on testosterone levels in the body except for men who are considered overweight. Other research has been conducted, but did not provide supplementation but rather determined levels in the body and correlation between Vitamin D present and testosterone levels (ie. Study #2).
Since Vitamin D is actually a steroid hormone (its labeling as a ‘vitamin’ is somewhat misleading) that is responsible for many functions in the body, it is very likely that a deficiency in Vitamin D would result in lower testosterone levels. Most people in the West are deficient in this vitamin due to lack of time spent in the sun and poor dietary habits, and thus supplementation with around 5000IU of Vitamin D per day would likely result in increased testosterone up to ‘normal’ levels for most people when taken continually over a period of time.
It makes sense that study #1 found an increase in testosterone, due to the subjects actually taking a Vitamin D supplement (remember, no supplementation occured in studies #2 & #3), and these subjects being deficient in the vitamin in the first place.
Continued research will be evaluated to determine if Vitamin D does have a direct impact on boosting testosterone levels.