Does Vitamin D Raise Testosterone? Critical Review Of Research

Update 8/15/20. I was giving a podcast interview recently and was asked a question I don't think I've ever heard before: do vitamin D supplements raise testosterone levels? I had to say, at the time, while I was skeptical, I was not 100% sure. Curious about this, I did make a note to myself to look into it afterward. Sure enough, after the interview was over, a quick online search revealed a lot of people asking that same question and many websites giving a resounding yes, that vitamin D did raise in fact testosterone levels! With respect to those other websites, I preferred to do my own investigation on this issue.  Fortunately, there are studies on this topic. Because vitamin D is so popular, I also want to answer other common questions too. Keep reading and let's see what I discovered. Also, read the Tribulus Terrestris review. 

 

Who's Lacking Vitamin D?

Vitamin D (also called calciferol and cholecalciferol) is not in many foods so getting enough may be more difficult than some think. As I see it, those who might be at the greatest risk include:

• • Older adults and those in nursing homes

• Overweight individuals
• People who live in the north where sunlight is scarce
• Those who spend most of the time indoors
• Those who regularly cover most of their body in clothing
• People with dark skin

There are also some medical conditions and medications that can cause cholecalciferol deficiency but I wanted to mention groups that don't get enough attention in my opinion.

Vitamin D and Testosterone?

Why might vitamin D be related to testosterone levels? Well, I've said for a long time, if calciferol were discovered today, it would probably not be called a vitamin. It would probably be called a hormone.

Vitamin D (and vitamin A) looks more like a hormone than vitamins. And, like hormones, vitamin D appears to have a wide rage of effects. While cholecalciferol is well known for its role in bone health, research suggests it may also take part in helping:

• Immune health
• Cancer
• Asthma
• Depression
• Parkinson disease
• multiple sclerosis

These diverse health conditions – and others – point to vitamin D as more of a hormone than a vitamin. Since hormones tend to look like each other and have different effects depending on the tissue we are talking about, it makes some sense how people might wonder if it could in some way be related to testosterone levels.

Indeed, as we'll see below, there are some studies that point to an association between testosterone and vitamin D as well.

Association vs. Cause & Effect

As you read through the research section below, you will see the word “association” used a lot. An association or correlation does necessarily not mean two things are connected to each other. For example, many people go to work when the sun comes up, but that does not mean the sun causes people to go to work. It just so happens that both often occur around the same time.

The same might be true with testosterone and cholecalciferol too.

Keep this in mind as you read the studies that show an association between vitamin D and testosterone levels.

Instead, pay more attention to the studies where vitamin D supplements were given to people to see if they actually raised testosterone or not.

Vitamin D & Testosterone Research

The best way to know for sure if vitamin D is related to testosterone is to test it. Here is a summary of the human research that's been conducted. I'm only going to cover the people's research because we are people and that's what's most relevant to us.  See the next section for a quick summary of the research.

Researchers in 2010, noted higher levels of testosterone were associated with higher D levels. This investigation involved 2299 men.

Researchers in Malaysia confirmed the previous study noting a significant association between testosterone and sex hormone binding globulin (SHBG) and vitamin D when they looked at 382 young men.

 

Hypogonadism refers to a condition where the testes are not making enough sex hormones, like testosterone. It appears that vitamin D is needed for proper gonad functioning.

Researchers in China noted low levels of vitamin D were associated with hypogonadism in 2845 middle-aged men. The average age of the men was 53 years.

Because low vitamin D and low testosterone can also be related to being overweight, the researchers speculated this may play a role in some of the cases they observed.

Ironically, these other researchers found just the opposite – that low D levels were not associated with hypogonadism or low testosterone in 225 middle aged men. Oddly, this study also suggested that too high levels of D might actually increase hypogonadism risk.

Researchers in Korea, looking at 652 middle-aged men, noted an association between calciferol and testosterone. The lower the D, the lower the testosterone; the higher the D levels, the higher the testosterone. This association varied by a change in seasons too.

 

One study that involved 54 overweight men (non-diabetic) did show that vitamin D supplements raised testosterone levels. The study lasted 1 year. The men were given either a placebo or 3,382 IU of vitamin D per day. It's important to know that the men started the study with below normal levels of both cholecalciferol and testosterone.

While this is encouraging, keep in mind because just because cholecalciferol might work in those who are deficient in vitamin D/testosterone does not necessary mean it also works in people who have normal or above normal hormone levels.

 

In one investigation resaerchers looked at 1362 men and noticed that higher cholecalciferol levels were associated with higher levels of testosterone. The connection however was not perfect because it seemed to vary according to where the men lived, being strongest for men who lived in the northeast and south but not elsewhere.

Interesting, but other researchers saw no increase in testosterone levels when reviewing previous studies where high dose vitamin D was given to men with low testosterone levels. The number of supplements used ranged from 20,000IU – 40,000 IU per week. Likewise, these researchers saw no change in cholecalciferol levels when testosterone was given to men either.

In 2015 researchers analyzed cholecalciferol levels from 3 different investigations to see if they were related to testosterone levels. The people in these 3 studies included:

• Men with heart failure
• Nursing home patients
• Men from the Netherlands

The amount of vitamin D used in the studies ranged from 600IU per day to 2000 IU per day. Unfortunately, these 3 separate studies showed no testosterone benefits from D supplements.

Sometimes, too much testosterone can be a problem, such as seen in women with polycystic ovary syndrome (PCOS). One study, involving 12 overweight/vitamin D deficient women, noted reduced total testosterone levels and blood pressure. This investigation lasted 3 months. Women were given cholecalciferol supplements that ranged from 3533 IU to 8533 IU per day.

Summary: Testosterone/ Vitamin D research

Reading the research can be confusing so here is a quick way to see all the research next to each other to help you make your own decision.

Study Name	Study Details	Study Results
Effect of vitamin D supplementation on testosterone levels in men	54 overweight men given 3,332 IU vit D for 1 year	Vitamin D raises testosterone
Supplementation with vitamin D does not increase serum testosterone levels in healthy males.	Vitamin D used ranged 20,000IU - 40,000 IU per week	Vitamin D does not raise testosterone levels
Vitamin D supplementation and testosterone concentrations in male human subjects.	results from 3 previous studies used. Vitamin D ranged from 600IU per day to 2000 IU per day.	Vitamin D does not raise testosterone levels
Association between plasma 25-OH vitamin D and testosterone levels in men	1362 men	Vitamin D associated with higher testosterone
Vitamin D is significantly associated with total testosterone and sex hormone-binding globulin in Malaysian men	382 men studied	Vitamin D associated with total testosterone and SHBG levels
Vitamin D is associated with testosterone and hypogonadism in Chinese men: Results from a cross-sectional SPECT-China study.	2854 men	Low vitamin D associated with hypogonadism
Serum vitamin D levels and hypogonadism in men.	225 middle aged men	Vitamin D not associated with hypogonadism or low testosterone
Therapeutic implications of vitamin D and calcium in overweight women with polycystic ovary syndrome	12 overweight/vitamin D deficient women	Vitamin D lowers total testosterone and blood pressure in women
Serum 25-hydroxyvitamin D levels and testosterone deficiency in middle-aged Korean men: a cross-sectional study.	652 men over 40	Vitamin D associated with testosterone levels
Association of vitamin D status with serum androgen levels in men.	2299 men	Vitamin D associated with testosterone levels

Remember, “associated” does not necessarily mean D promotes higher testosterone levels. I recommend paying the most attention to the the studies where D supplements were given to people.

How  Is Vitamin D Measured?

The only way to know for sure if you are deficient or not is to get a blood test. Here, doctors will do what's often called a “25-hydroxy vitamin D test (also called 25-OH cholecalciferol ). The test is pretty inexpensive, costing about $50. Usually, people do not need to fast for this blood test.

At home vitamin D tests are also available.

What's a Normal Vitamin D level?

What's normal for vitamin D is a bit controversial depending on who you speak with. While a level of 30 ng/ml is often thought of as good, that amount only considers bone health. It does not take into consideration the other health benefits of vitamin D. Because of this, some set optimal ranges between 20 and 40 ng/ml while others advocate for between 30 and 50 ng/ml.

In my opinion, 20 ng/ml is not enough for most people reading these words.

The Endocrine Society lists 30 -100 ng/ml as sufficient but that is a very big range. In other words, should everybody be striving for is 100 ng/ml?

Currently, the non-profit, Vitamin D Council, recommends people aim for 50 ng/ml. To me, that sounds like a nice middle value for most. Here is a quick comparison between the Endocrine Society and Vitamin D Council recommendations.

	Endocrine Society	Vitamin D Counsel
Vitamin D Deficiency	0-20 ng/ml	0-30 ng/ml
Insufficient in Vitamin D	21-29 ng/ml	31-39 ng/ml
Sufficient Vitamin D	30-100 ng/ml	40-80 ng/ml
Too Much/ Toxic Vitamin D		>150 ng/ml

The Vitamin D Solution by Dr. Michael Holick is a great book to learn more about this nutrient.

Natural Ways To Boost Vitamin D Levels

If a blood test indicates you are low in cholecalciferol, how do you raise it? Well, some would say that the easiest way is to go outside for a few minutes when the sun is at it's highest point in the sky (10 AM-2 PM). But that might not work for everybody such as older adults and those who live in more northern regions of the world.  Also, our dermatologist friends will also rightly point out that too much sun can cause wrinkles as well as skin cancer.

Tanning beds probably won't help because most tanning beds only provide ultraviolet A rays (UVA rays). While UVA rays can cause skin cancer, they don't help the body make vitamin D. It's only UVB rays that make vitamin D.

Because vitamin D is a fat-soluble vitamin, it is stored in our fat cells. When we lose weight, those fat cells release the vitamin, which in turn improves blood levels.

Foods /products that contain cholecalciferol include:

• Salmon
• Tuna
• Milk/almond milk
• Yogurt
• Egg yokes
• Most protein powders
• Shiitake mushrooms

All that said, I think the most efficient way to raise vitamin D would be through supplementation.

When using over-the-counter calciferol supplements, a good rule of thumb to remember is that:

• 1,000 IU will raise blood vitamin D levels by about 10 ng/ml
• 2,000 IU will raise blood vitamin levels by about 20 ng/ml

Once you know your test results, you can pick a supplement that's right for you.

D3 vs D2? What's Better?

There are two types of nutrient found in supplements:

• • Vitamin D3 – also called cholecalciferol (comes from the sun)
  • Vitamin D2 – also called ergocalciferol (comes from yeast)

It's often said that D3 is better than D2 because vitamin D3 is what we make when we go outside. Studies do seem to show D3 as better than D2 at raising blood levels of this nutrient but I don't believe that means D 2 is useless. I say this because several studies have shown that vitamin D2 can reduce falls in older adults

If D2 was less potent than D3, why has it shown benefits?

While we might absorb D3 better, for the most part, I believe D2 and D3 are probably equally potent in many health benefits. This is good news for vegans who may prefer ergocalciferol.

Do You Need A Vitamin D Test?

When I give seminars, I often ask what supplements people take. For most, vitamin D is on the list. Many admit to taking the vitamin for many reasons (although testosterone is never on that list). But, when I ask the follow-up question “have you had a vitamin D test?” Most say no.

When cholecalciferol started to become sexy, many people started getting tested to see if they were lacking or not. Since then, there has been a backlash where some are saying testing are not necessary. I'm not sure if I agree with that.

Remember, cholecalciferol is a hormone-like compound. I'm usually not a fan of do-it-yourself hormone therapy  because I don't know what that will do.

I also can't tell by looking at someone who is deficient. Even the people you'd think were fine might not be. As proof of this, I remember attending a conference once where the speaker – who was training for a triathlon – admitted to being deficient in vitamin D. This person was a young white guy who was spending much of his time outside swimming, running and biking  – and yet he was still low!

Because of this, I recommend getting tested. This is especially true for those groups I highlighted at the beginning of this review.

So Does Vitamin D Raise Testosterone?

Over the years, I've met several seemingly healthy people who turned out to be low in vitamin D. While the research is intriguing, I'd still like to see a few better studies on the raising testosterone issue. For now, if I were asked the “does vitamin D raise testosterone” question again, I'd reply that if it really worked, it might be most likely to raise the hormone in those who were already low in vitamin D and testosterone to begin with.  How likely it might work I could not say because research is not as complete as I'd like. For now, I do not feel vitamin D supplements raise testosterone in those who already have enough of these compounds.

How Do You Feel About That?