Vitamin D Deficiency: Does It Cause Hair Loss?

Can a vitamin D deficiency cause hair loss? One reader's anecdote and a growing body of literature suggests yes. This article explores how lacking vitamin D can hinder hair growth, and how to safely raise vitamin D levels. Note: supplementation isn't always the answer. In many cases, it's actually dangerous.

Edited and reviewed by:
Rob English, Medical Editor

The Vitamin D-Hair Loss Connection

When it comes to the causes of hair loss, most people never suspect a vitamin D deficiency.

Here’s a story about why you should, and why vitamin D can sometimes make the difference between hair loss and hair recovery.

Jared’s Story

You might’ve seen Jared’s photos on the site. Jared and I started communicating in May of 2014. We exchanged emails to clarify the massage techniques and supporting evidence, then kept in touch for troubleshooting and research-sharing.

Anyway, here are photos of Jared’s hair regrowth over the full year:

Natural hairline regrowth

His hair recovery is encouraging, but his photos don’t tell the full story. Because around the five-month mark, Jared actually lost most of the hair he’d recovered. The question was: why?

Jared’s Story Of Hair Recovery

Jared started the book’s protocol in the spring and saw signs of thickening relatively quickly. But around winter, his regrowth had stalled. Then came thinning at his hair line, and two months later, his hair was receding again.

This didn’t make sense. In the summer and fall months, Jared saw tremendous regrowth. He hadn’t changed his massage technique. He hadn’t changed his diet. And on top of his hair loss, Jared now also felt depressed.

Jared decided to find out why, so he ordered some blood work – including a 25-hydroxy vitamin D test.

25-hydroxy vitamin D is (debatably) the standard for measuring how much vitamin D is in our body. For anyone who’s done the test, a deficiency is labeled as anything below 30 ng/ml. Depending on your doctor, some even say readings below 40 ng/ml should be marked as a deficiency.

So what were Jared’s 25-hydroxy vitamin D levels? 8 ng/ml. He was severely vitamin D deficient.

Who Cares About Vitamin D?

Vitamin D is critical for hundreds of functions in the body – from wound healing to hormone production to immune functionality. And in winter time, a vitamin D deficiency is extremely common – a clear indicator being depression. There’s even a name for it: Seasonal Affective Disorder.

Jared was definitely symptomatic, and his hair was no longer progressing. Was a vitamin D deficiency contributing? He decided to address the deficiency and find out.

Was Jared’s Recent Hair Loss Caused By Low Vitamin D?

Jared changed his diet to include more foods rich in vitamin D. He also started supplementing with vitamin D3 (and its adjuncts – including, but not limited to, vitamins A and E).

Within a month, Jared felt better. By spring, he was experiencing hair gains beyond his initial progress. And by month eleven, Jared had made a near-complete pattern hair loss recovery.

So what can we glean from this story?

For Some People, Vitamin D Might Be Critical For Hair Regrowth

If Jared hadn’t tested his vitamin D levels, he might not have regrown any hair. He probably would’ve seen the thinning at month five and thought, “Well, I guess this protocol doesn’t work me.”

Instead, Jared analyzed his symptoms, tested his vitamin D, discovered a deficiency, then took action to increase his vitamin D intake. The end-result: a better mood and significant hair recovery.

So just how important is vitamin D? For Jared, vitamin D was the missing link for success. And for many others, the same could be true.

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Vitamin D Deficiency Is A First World Epidemic

Forty years ago, you’d be hard-pressed to find anyone with a vitamin D deficiency. Nowadays over 40% of Americans are severely vitamin D deficient – including me at one point.

This isn’t good. Vitamin D receptors are found in nearly every cell inside our body. Vitamin D is a prerequisite for brain function, hormonal balance, and even the prevention of certain cancers. And in a recent study, over 70% of heart disease patients were found to have low levels of vitamin D.

Given heart disease’s relationship to male pattern baldness, could a vitamin D deficiency also cause pattern hair loss?

The answer is a strong maybe.

The rest of this article uncovers a few (of many) pathways that a vitamin D deficiency can exacerbate hair loss, and what we can do to get our vitamin D levels back on track.

What Is Vitamin D?

Vitamin D is a fat-soluble vitamin. There are a few different kinds, but in its active form, vitamin D isn’t actually considered a vitamin – it’s considered a hormone.

How Do We Get Vitamin D?

We get vitamin D from eating certain animal products (like eggs and fatty fish). But we actually make the majority of our vitamin D when our skin comes into contact with the sun’s UVB rays.

Our skin contains a steroid called 7-dehydrocholesterol. When UVB light connects with this steroid, the photons break apart one of 7-dehydrocholesterol’s chemical bonds, which then converts the steroid into vitamin D3 (an inactive form of vitamin D).

Vitamin D3 then makes its way to the kidneys and liver where it gets converted into the active form of vitamin D – calcitriol. The active vitamin D then gets transported to any cells, tissues, and organs in need – influencing gene expression, immune function, calcium uptake, neural signaling, and everything in between.

All else equal – when our vitamin D levels are adequate, our bodies are well-equipped to keep our health and hormones in check. But if we’re vitamin D deficient, things can start going wrong… Things like decreased immune function, autoimmunity, reduced bone density, and even hair loss.

Low Vitamin D Is Associated With Hair Loss In Both Men And Women

When it comes to vitamin D and hair loss, the research is clear:

  1. Women 18-45 suffering from sudden onset hair loss tend to have low vitamin D2 levels.
  2. In men and women, a vitamin D deficiency is closely associated with hypothyroidism – of which a commonly reported symptom is hair loss.
  3. In premenopausal women, insufficient sun exposure (and likely low vitamin D) is associated with an increased risk of autoimmune thyroid disorder. And the lower your vitamin D, the worse your thyroid condition. In fact, 92% of Hashimotos sufferers – the autoimmune form of hypothyroidism –  have low serum vitamin D markers.

But while low vitamin D is associated with both hair loss and hypothyroidism, does a vitamin D deficiency actually cause hair loss?

This is a little harder to answer.

Low Vitamin D Is Related To Hair Loss, But It’s Unclear If It Causes Hair Loss

I’ve yet to find a study showing that a vitamin D deficiency directly causes hair loss (association and causation are two different things).

However, there’s plenty of evidence showing that a vitamin D deficiency contributes to the conditions that precede a balding scalp:

  1. Fibrosis
  2. Calcification

Let’s start with fibrosis – what it is, how it contributes to pattern hair loss, and where vitamin D comes into play.

Fibrosis-Hair Loss-Vitamin D Connection

What Is Fibrosis?

Fibrosis is another term for “excess collagen”. It’s when our bodies over-accumulate connective tissue, and it often occurs during cases of 1) large wounds, or 2) chronic inflammation. The end-result of fibrosis: scarring.

Fibrosis is found all around thinning and miniaturized hair follicles. In the scalp, fibrosis is called perifollicular fibrosis, and to put it simply, it’s when our hair follicles become entrapped in scar tissue.

This scar tissue (fibrosis) then restricts blood flow to the hair follicles, thereby lower its oxygen levels. The follicles then shrink, which causes the hair to thin, until it eventually disappears – leading to pattern baldness. (Note: here’s an article explaining how fibrosis and calcification precede hair loss).

Low Vitamin D Promotes Fibrosis

There are two ways that a vitamin D deficiency promotes fibrosis:

  1. A vitamin D deficiency increases the expression of the protein toll-like-receptor 4
  2. A vitamin D deficiency increases the expression of the protein transforming growth factor beta

Mechanism #1: Toll-Like-Receptor 4

The causes of fibrosis are elusive, but researchers may have just recently discovered a mechanism: the activation of toll-like-receptor 4 (TLR4).

TLR4 is a protein that helps activate our innate immune system (our body’s immediate defense to threatening bacteria, pathogens, or toxins). It turns out that TLR4 is higher in areas where there’s fibrosis. Moreover, TLR4 is higher in patients with scleroderma – a condition where the body rapidly accumulates scar tissue for no clear reason.

In a recent study on mice, researchers uncovered that if they modified a gene so that mice could not express TLR4, they could make those mice immune to scleroderma. These TLR4-absent mice developed very little – if any – fibrosis during treatment.

Without Vitamin D3, TLR4 Expression Skyrockets

Vitamin D3 has been found to significantly decrease the expression of TLR4. In some human studies, vitamin D3 decreases TLR4 by nearly five-fold – depending on D3 dosage and time elapsed.

What does all this mean?

Vitamin D3 modulates TLR4 expression. The higher the D3, the less TLR4 expression, the less fibrosis.

The lower the D3, the more TLR4 expression, the more likely fibrosis develops.

Mechanism #2: Transforming Growth Factor Beta (TGF-β)

Transforming growth factor beta (TGF-β) is a signaling protein. Nearly all our cells use TGF-β for one process or another, and in normal amounts, TGF-β is critical for cellular repair.

However, when TGF-β runs rampant, fibrosis soon follows. And the more TGF-β, the more fibrosis. Knowing this, it should be no surprise that TGF-β is elevated in the scalps of balding men.

Vitamin D Receptors Downregulate TGF-β

Interestingly, vitamin D receptors decrease the expression of TGF-β. The more vitamin D receptors present, the lower the TGF-β. And unfortunately this works the other way too. In the absence of vitamin D receptors, TGF-β skyrockets with fibrosis soon following.

Our goal is keep our hair, which means we want to minimize the development of any fibrotic process. Without vitamin D, we’re far less equipped to keep fibrosis at bay.

To make matters worse, vitamin D’s role in hair loss extends far beyond fibrosis – and even to the promotion of calcification.


Calcification-Vitamin D-Hair Loss Connection

What Is Calcification?

Calcification is the build-up of calcium deposits in the body.

Dr. Frederick Hoelzel first published the connection between scalp calcification, restricted blood flow, and baldness over 70 years ago. While studying cadavers, he found that areas of baldness occurred in regions where the scalp was calcified:

“Baldness occurred in persons in whom calcification of the skull bones apparently had not only firmly knitted the cranial sutures but also closed or narrowed various small foramens through which blood vessels pass most prominently in persons with a luxuriant crop of hair.”

Fibrosis Calcification Hair Loss

Just like fibrosis, calcification precedes hair miniaturization. Arterial calcification acts a blockade to proper blood flow. Since blood carries oxygen, this lowers the oxygen levels of tissues that any “calcified” capillary supports (namely, our hair follicles). Without enough oxygen, our follicles begin to shrink – and eventually disappear entirely.

So where does vitamin D come into play?

Low Vitamin D Is Associated With Increased Vascular Calcification

In some populations, a vitamin D deficiency is associated with increased rates of arterial calcification and even heart disease. Moreover, evidence shows that calcification is higher in those with fewer vitamin D receptors (receptors are activated through vitamin D metabolites – meaning the more vitamin D you have, the more receptors are active).

There’s even evidence of the specific mechanisms by which low vitamin D increases calcification.

Mechanism #1: Low Vitamin D Increases Prostaglandin D2 Expression

You might’ve heard of prostaglandin D2 (PGD2) before. Prostaglandin D2 (PGD2) is a fatty acid derivative, and in 2012, it made headlines when hair loss researchers discovered that

  1. Prostaglandin D2 is elevated in the scalps of balding men
  2. When PGD2 increases too much, human hair stops growing and even recedes

It should be no surprise that PGD2 induces calcification… Meaning that the more PGD2 present, the more likely you are to develop calcification in the affected tissue.

Interestingly, vitamin D3 decreases PGD2 expression – and thereby may prevent calcification (the same calcification that precedes hair loss). And of course, without vitamin D3, the opposite is true. PGD2 increases, and resultantly, so too might calcification.

But PGD2 isn’t the only mechanism by which low vitamin D encourages calcification and (indirectly) hair loss.

Mechanisms #2 And #3: Vitamin D Deficiency May Increase Calcification-Inducing Proteins

In the absence of vitamin D, our arteries begin to over-express proteins associated with inflammation and calcification induction. If over-expressed for too long, these proteins (known as calcification inducers) tend to promote tissue calcification.

Two sets of calcification-inducing proteins that increase in the presence of a vitamin D deficiency are…

  1. Pro-inflammatory cytokines
  2. Matrix metalloproteinases (MMP)

The net: if you’re vitamin D deficient, you’re more likely to over-express PGD2 and these proteins, which puts you at a higher risk for arterial calcification… The same calcification implicated in pattern hair loss.

Summarizing The Triggers – How Low Vitamin D Causes Hair Loss

In men and women, infrequent exposure to sunlight and/or low vitamin D is associated with hair loss. Interestingly, low vitamin D is also associated with fibrosis and calcification – two chronic, progressive conditions that may precede hair loss and trigger hair miniaturization.

Low vitamin D might indirectly trigger pattern hair loss by encouraging…

  1. Fibrosis (by increasing the expression of TLR4 and TGF-β).
  2. Calcification (by increasing the expression of PGD2, pro-inflammatory cytokines, and MMP).

Now that we know the mechanisms, let’s ask the question that really matters…

Will Increasing Our Vitamin D Status Help Prevent Or Reverse Pattern Hair Loss?

The answer is a strong maybe, and the research is encouraging.

How Adequate Vitamin D Protects Against Pattern Hair Loss

Benefit #1: Vitamin D May Prevent Arterial Calcification

I’ve previously written about the importance of hormonal health, and how testosterone and estrogen are both implicated in not only hair loss, but arterial calcification.

To summarize: evidence shows that testosterone and estrogen (or our testosterone:estrogen ratio) might help mediate the accumulation of calcification.

In men, lower testosterone levels are associated with higher rates of calcification and stroke. Moreover, men with higher estrogen levels are also more likely to develop arterial calcification.

With heart disease and arterial calcification reaching epidemic proportions, it should be no surprise that men’s testosterone levels today are 22% lower than they were 30 years ago.

If men want to protect themselves from arterial calcification, heart attacks, and even hair loss – there’s plenty of evidence to suggest that increasing testosterone levels (naturally) is protective.

So where does vitamin D come into the equation? Well, it turns out that vitamin D has a huge impact on testosterone.

In Men, Vitamin D Increases Testosterone Levels

Men with healthy vitamin D levels have significantly higher testosterone than men who are vitamin D deficient.

Another study shows that men supplementing with vitamin D3 for one year increased testosterone levels 25% higher against the placebo.

Even more surprisingly, one study revealed that exposing men’s chests to UVB radiation for a few minutes per day for five days straight increased total testosterone by a whopping 120%. And even more interestingly… When the genitals were exposed, total testosterone increased by 200%.

The relationship seems clear: the more UVB radiation (without burning), the more vitamin D, and the higher the testosterone. Given endogenous testosterone’s protective effects against calcification, it should be no surprise that serum vitamin D status is inversely correlated with arterial calcification.

If we want to protect ourselves from arterial calcification (and hair loss), it’s in our best interests to start getting more vitamin D.

Benefit #2: Vitamin D Might Directly Encourage Hair Regrowth

Some research suggests that UVB radiation (from the sun) and vitamin D3 might be a necessary mediator for the generation of new hair follicles. See these studies here and here.

In other words – sunlight and vitamin D might be a prerequisite for new hair follicle proliferation. If we’re not getting enough of either, hair growth might be harder (or impossible) to achieve.

Summarizing The Benefits Of Vitamin D

Vitamin D may be a critical (and overlooked) factor in fighting hair loss. Here’s a summary of its benefits:

  • Vitamin D prevents fibrosis by reducing TLR4 and TGF-β
  • Vitamin D prevents calcification by reducing the expression of PGD2, pro-inflammatory cytokines, and MMP
  • Vitamin D and UVB radiation increases testosterone levels in men
  • Vitamin D and UVB radiation increase hair follicle proliferation, and may even be necessary for hair regrowth

Given the above evidence, and given the fact that the majority of Americans are vitamin D deficient, it’s time to start upping our levels. But if we’re going to increase our vitamin D, we need to be smart about it.

How To Increase Our Vitamin D Status (And Support Our Hair)

Recommendation #1: Be Careful About Vitamin D3 Supplementation

Before you start popping D3 supplements at 50,000 IU’s daily, please know there is an upper limit to vitamin D. And if there’s anything we’ve learned in the last two decades of vitamin research, it’s this:

Nutrients and vitamins in their isolated forms don’t always behave the way we expect. Why?

Many of these nutrients and vitamins require other nutrients / vitamins for proper synthesis. Supplementing one nutrient in the absence of its cofactors can lead to problems.

Fifteen years ago, doctors used to recommend supplementing with vitamin D3 alone. Then after a few years, researchers realized that supplementing with vitamin D3 without the proper amounts of vitamin A, vitamin K2, and magnesium actually increased patients’ risk for arterial calcification.

The take away: if you’re going to supplement with any vitamin or nutrient, make sure you’re also including that nutrient’s adjuncts and cofactors.

Too Little And Too Much Vitamin D Can Trigger Arterial Calcification

That’s right. In its supplemented form, too little and too much vitamin D can cause inflammation and arterial calcification. The only difference? The mechanisms.

Here’s a visual showing the relationship between vitamin D dosage, the risk of under- or over-supplementing, and the purported mechanisms of action:


Long-story short: be careful about vitamin D3 supplementation.

Still Want To Supplement With D3?

If you’re going to supplement with vitamin D3…

  1. Don’t go wild with the dosage. Evidence shows 2,000 – 5,000 IU’s per day is safe for most people.
  2. If you’re going to go wild, make sure you’re including vitamin D’s proper adjuncts – vitamin A, vitamin K2, and magnesium (among others) – and also through food sources. (Jared did mega-dose on vitamin D, but he was smart about it!)

But there’s an even better (and safer) way to optimize your vitamin D levels: UVB radiation. Or in other words, the sun.

Recommendation #2: Start Getting Into The Sun

If you want to increase your vitamin D safely and naturally, your best bet might be to expose yourself to the sun and as often as possible (without burning).

A few years ago, I decided to reorient my entire schedule toward getting healthy amounts of sun. Even though I live in San Francisco, this wasn’t easy. San Francisco gets some sun throughout the year, but I also work a full-time job outside of this site. I’m inside an office at least forty hours per week, and my commute to work is about ninety minutes total per day. When I leave my apartment each morning, there’s little to no sun. When I arrive home each night, there’s little to no sun.

Why is this a problem? Well, evidence shows that our ability to synthesize vitamin D is directly dependent on the sun’s angle on the Earth. That means that even if it’s a sunny cloudless day, vitamin D synthesis still depends on:

  1. Latitude. Anyone above 33 degrees North of 30 degrees south (in latitude) might not be able to produce vitamin D during winter months.
  2. Time of day. 10am to 3pm is when the sun is highest and there’s more potential for UVB radiation.
  3. Time of year. The sun’s angle shifts with the seasons, and summer time is your best bet for maximum vitamin D synthesis.

A good rule of thumb: if your shadow is as tall or shorter than you, there’s usually enough UVB radiation present for vitamin D synthesis.

When I took into consideration all of this – my location, working hours, and lifestyle – I realized the only way I was going to make any natural vitamin D was if I could get daily sun exposure during working hours.

What did I do? I started packing a lunch. Then I stopped scheduling meetings during my lunch break. Then I started jogging and walking everyday at noon. I found quiet areas to walk with fewer walkers around, and to maximize my sun exposure, I wore shorts and went shirtless. I ended up getting 30-45 minutes of near full body sun exposure daily… Something I still do to this day.

But I didn’t stop there. Each weekend, I made an effort to hike or exercise wherever the sun was shining. Sometimes that meant driving 45 minutes out of the city. Sometimes that meant going to the beach with friends. Whatever the case, it didn’t matter to me – so long as I was getting daily sun exposure between the hours of 10am and 3pm.

A few months in – I felt happier, looked healthier, and even found myself recovering faster from the scalp massages.

But with all that sun exposure, am I now at risk for too much vitamin D, and thereby the same calcification risks we see with those supplementing aggressively on vitamin D?

Can We Get Too Much Vitamin D Through Sun Exposure Alone?

Theoretically, it’s possible. One study on Israeli lifeguards showed that excessive sun exposure (three-five hours per day, most days per week, for years) increased the lifeguard’s serum 25(OH)D3 levels to near mega-supplementation levels, and that these lifeguards have a near 20-fold increased incidence of kidney stones (read: calcification).

But that’s an extreme example – and something no one with an office job could even dream of achieving. On top of that, there’s a good chance that if these Israeli lifeguards supported their high serum 25(OH)D levels with adequate vitamin A, vitamin K2, and magnesium – that incidence of kidney stones would’ve dropped dramatically.

For 99.99% of us, vitamin D toxicity through sun exposure alone is highly unlikely. The reason why? Our bodies have a built-in mechanism that prevents vitamin D toxicity through sun exposure… It’s called a sunburn.

Sunburns: Our Built-In Protection From Vitamin D Toxicity

After a long enough exposure, the sun’s heat on our skin “photo-degrades” the precursors for vitamin D3. This stops our bodies from overproducing vitamin D3 – which is especially important if we’re absent of vitamin D3’s proper adjuncts and cofactors. This is the major difference between supplementation and natural vitamin D3 synthesis. Supplementation is unchecked, whereas our natural D3 synthesis is carefully regulated.

Beyond Vitamin D: Sunlight Also Improves Blood Pressure

The benefits of actual sunlight extend far beyond vitamin D alone. It turns out that sunlight may also stimulate the production of nitric oxide – a known vasodilator – in our blood vessels, which can significantly lower blood pressure and improves blood flow.

Net – if you can do it, sunlight is better than supplementation… which brings up another question. What about sunscreens?

If You Want To Raise Vitamin D Levels With Sunlight, Avoid Sunscreens

For one, sunscreens block UVB light, and UVB light is the spectrum we need to synthesize vitamin D3. The more UVB blocked, the less vitamin D3 created, the less benefit you reap from the sun.

Secondly, sunscreens are full of the same ingredients we’re trying to avoid in shampoo – phthalates, parabens, and other endocrine disruptors. When you put on sunscreen, you’re rubbing these compounds into your largest organ – your skin – and all over your entire body.

Thirdly – and this is a big one – studies show that sunscreen users are actually more likely to burn than non-sunscreen users! Why? It’s simple: sunscreen gives people a false sense of “long-lasting” sun protection… But most sunscreen users never reapply. After an hour or so, sunscreen’s effectiveness wears off, but sunscreen users continue to sit in the sun without reapplying and assume they’re still protected. The end result? They get burned, and often badly. Non-sunscreen users are able to gauge the sun’s intensity more easily – because they can literally feel its heat on their skin (when you apply sunscreen, this sensation slightly dissipates). As a result, they’re more aware of when they’re starting to burn, and thereby more likely to cover up before a burn turns severe.

If you feel like you’re burning, cover up or sit in the shade. When I’m outside and my skin starts to feel too hot, I cover-up with a large hat and sometimes a sarong (light towel). The combo makes me look ridiculous, but who cares?

With that said, please be cognizant about your sun exposure. Know your limits.

Final Vitamin D Takeaways – For Heart Health And Hair Growth

On the one hand, low vitamin D levels are associated hair loss and hypothyroidism. Those with low vitamin D also suffer from increased rates of arterial calcification and fibrosis. Both calcification and fibrosis precede hair loss. It’s likely that low vitamin D contributes to hair thinning through the mechanisms by which it promotes calcification and fibrosis.

On the other hand, high vitamin D levels – achieved through either mega-supplementation or inhuman amounts sun exposure – also promotes calcification and through entirely different mechanisms. This is especially true when vitamin D is supplemented blindly and without its proper adjuncts.

If you have the choice, always opt for sunlight exposure over a vitamin D3 supplement. Get sunlight between the hours of 10am-3pm when our bodies are capable of synthesizing vitamin D3 from the sun. Aim for 15-45 minutes per day, with as much skin exposure as possible, but adjust this depending on your comfort level and your likeliness to burn (don’t overdo it).

If you can’t reorient your schedule, don’t have access to sunlight, or it’s winter time, you can take a D3 supplement… But don’t abuse that supplement, and be sure to also consume with vitamin K2 and magnesium. On top of that, ensure that you’re getting enough vitamin A in your diet through beef and chicken liver.

Lastly – and it bears repeating – I don’t suggest you bake in the sun for six hours each day. With most work schedules, that’s not really possible anyway. However, getting 15-45 minutes of sun exposure daily will help lift your levels significantly – so shoot for whatever is manageable and without overdoing it.

Questions? Please reach out in the comments section!

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62 thoughts on “Vitamin D Deficiency: Does It Cause Hair Loss?”

    • Absolutely. I think that nutrition (and thereby the fat soluble vitamins A, D, E, and K) is critical not only for our hair but for health in general. Vitamin A has been found to have regulatory effects on sebum production (which is the basis for the drug Accutane). Vitamin K2 is a cofactor for vitamin D and a key mediator for calcium movement. The challenge lies in determining – for each individual – how much of a factor any one vitamin is in regards to the causes of a person’s hair loss. What the research shows lately is that a vitamin’s “recommended dose” established by the FDA isn’t necessarily the “therapeutic dose”. So we might all be under-consuming an overwhelming amount of vitamins and minerals. Couple this with less-than-stellar diets, lifestyles, gut flora, lacking sleep, etc. – and it gets very difficult to pinpoint what’s causing a person’s hair loss – even in the presence of a few vitamin deficiencies!

      • Hello,
        This post gives me hope. I have similar hairloss on the temple and also alopecia areata. Checked my vitamin D levels and it was 7.8 ng/ml ! Now I’m supplementing and eating a proper diet.

      • Hey Neo,

        Thanks for your message. With vitamin D levels that low, I’d also be sure to check for hyperparathyroidism (a condition highly correlated with some forms of hair thinning). I’d recommend another round of tests for serum vitamin D, calcium, TSH, and PTH. You can read more here:


        I’d be careful about supplementation before ruling out hyperparathyroidism — as vitamin D supplementation in the presence of hyperparathyroidism can actually exacerbate arterial calcification.


  1. Phaneendra, you can get blood tests to check your vitamin d level
    This was a very informative article
    I always supplement with vitamin d and k with organic sea iodine in winter months, we don’t get much sun here in England then!!

  2. Wow, quite comprehensive, detaile article but simple to understand! Coincidentally, I read some other research regarding sunlight and hair growth, I wondered if that’s true and here’s the other answer.

  3. I live in the northern part of Sweden so I have to rely on supplementing with vit D3. If I eat 2.500 iu/day..do I have to supplement with A, K2 and Mg or is that only necessary with higher intake of D3? And also….in a diet deficient in omega 6 (wich is good ofc), it’s really difficult to get enough vit E! How to get enough vit E??? Supplementation needed?

    • Hey Cammi – if you’re minimizing your omega 6 intake, you’re also likely reducing your need for vitamin E:


      In any case, you should still try to get vitamin D’s adjuncts – especially if you’re supplementing. You can eat liver for vitamin A (retinol), certain cheeses for K2 (or a supplement), and maybe consider a supplement for vitamin E.

    • I’m sorry to hear about your situation, Denise. Alopecia areata often has a different etiology than pattern hair loss. And I’m terribly sorry to hear about your health. I wish you the best in your recovery.

    • Scalp massage, vitamin D supplementation (with cofactors / adjuncts), Ray Peat-inspired diet, and a handful of other dietary / lifestyle changes focused on minimizing systemic inflammation and supporting the thyroid. He’s one of the videos interviews included in the book, so if you’ve got it, the video plus the transcript covers the full 80-minute interview.

  4. Rob. Could this be the reason that vegans find it hard ?? As Vitimin d is present in a lot of dairy food.

    Another question about demographics and diet. Japanese people are known to have the highest lifespan, and minimal hair loss in their history.. could this be due to their diet highe in super foods such as , sweet potato, fish, green tea ??


    • It’s definitely possible. Vegans have significantly lower levels of serum 25(OH)D versus omnivores because of 1) a low vitamin D diet and 2) low vitamin D synthesis (driven by lacking ingestion of fat and fat-soluble vitamins).

      Surprisingly, the difference for males in Japanese versus American life expectancy is only four years. What’s more important to focus on is quality of life – of which the Japanese are reigning champions. This is due to a multitude of factors – diet being one of them (including the foods you’ve listed). Other unmentioned factors: 1) daily movement, 2) sun exposure, 3) microbiome, and 4) a sense of community. So you’re probably right, though diet is just one (of many) factors.

  5. Hi rob,
    This might not be a good question but do you plan to make your book free in the future just as danny did with his hair like a fox (i got that for free).

    • Hey Piyush – I don’t have plans to make the book free, at least any time soon. Danny Roddy’s income model is much different than mine. Danny runs a Patreon campaign where he promises weekly content to those who support him. To my knowledge, his full-time focus is energy / hair loss research – and so he’s able to fulfill those content demands on a regular basis. I work a full-time job in addition to running this site, so I can’t run the same model. When I get busy at work, I have less time to devote to new content, which means I can’t produce new articles or videos on a regular basis. That’s why I’ve decided on my current model.

  6. Hello Rob
    If ur doing the DT massages as explained in ur video and also on lipogaine or minoxydil would we expect
    to lose any hair regained? Shouldnt the massage be breaking down the fibrosis and calcification so when enough regrowth has been achieved one can drop the minoxydil without losing gains? People who make gains on minoxydil do so because it acts as a vasoconstrictor in the telogen phase of any particular hair strand at any given moment. Therefore when you stop the medication, of course u lose gains if the scalp is still calcified or fibris. Would there be any other reason why stopping minoxydil while doing DT cause shedding? That would just tell me the DT regimen is not working. DT and minoxydil should b working hand in hand without any shed? !

    • It’s a tough question to answer – the reason being that no one’s exactly sure how minoxidil works. Here’s just a short list of minoxidil’s mechanisms:

      1) It increased blood flow (vasodilation)
      2) It’s a potassium channel opener
      3) It increases PGE expression

      The issue is that no one’s really sure how to weight these purported mechanisms. As in, no one’s really sure which one is helping the most for hair regrowth.

      On top of that, no one’s entirely sure why many people shed when they first start taking minoxidil. And when you stop using minoxidil, you typically lose any hair you grew from the drug within four months.

      Now if minoxidil’s MAIN mechanism of action is increased blood flow, then most people shouldn’t shed if they’re doing DT + Rogaine, then after seeing regrowth, just switch only to DT.

      We’re also only beginning to understand all the mechanisms involved in mechanical stimulation. So unless the mechanisms of DT and the mechanisms of Rogaine line up perfectly, there’s always a chance you might experience some shedding once dropping Rogaine. There’s just not enough literature in either case – even with Rogaine being one of the most studied hair loss drugs.

      With that said, I dropped Rogaine when I started doing DT, and I’d used Rogaine for ~7 years straight. I did shed (to what degree was from massaging versus Rogaine withdrawal is debatable, and there’s no way to prove it either way). But I also later recovered the hairs I shed.

      Your shed probably depends heavily on when you stop using Rogaine. If it’s many months into regrowth via DT, then you’ll probably shed less as you’ve hopefully cleared away some fibrotic tissue. If it’s the second you start DT, then you’ll probably shed a bit more.

  7. Rob,
    If we were to supplement with Vitamin D3 what should it’s ratio be with Vitamin A, E, K2, and Magnesium? Should I just aim for the daily recommended value in each or scale upwards due to hair loss? (I’m considering supplementing with 4,000 IU of Vitamin D3.)

    • Hey Jamey – it’s tough to say what the correct ratios of vitamins A, E, K2 and magnesium should be (which is why I like to stick to food versus supplementation as often as possible). I’d aim for a minimum of the daily recommended value (the therapeutic dose is often much higher). If you’re taking 4,000 IU’s of D3 daily throughout winter, I’d also suggest eating a few ounces of liver weekly for vitamin A and K2, along with any other sources of K2 listed in the book. For vitamin E – if you’re also minimizing omega 6 fatty acid intake, you generally require less vitamin E. But it won’t hurt to supplement with E throughout winter and at whatever the recommended dose is. With that said, I’d focus most on K2 and A.

  8. Hi Rob.

    Here’s a possible theory:

    Men get pattern baldness, including the crown. Not all over the head, generally all at the top.

    Men were/are the hunter/gatherers, the women stayed home.

    Women generally don’t go bald. They certainly don’t go bald in the way we do.

    So maybe Mother Nature invented MPB to allow men, especially in northern latitudes where the sun doesn’t give the vitamin D a bald head to taken in more UV!


  9. If balding is from sebum buildup and calcification, how do you explain hair thinning in the temple and front hairline where the skin is more loose and pliable? And I don’t suppose you can stop or reverse hairloss in these areas from massaging?

    • Great question, and something that a few others have asked. Please see this comment:


      Your question about hairline regrowth is also addressed there. Many readers have reported regrowth at the hairline from the mechanical stimulation exercises, and all the evidence suggests that regardless of relative elasticity, recoveries in those areas are still very possible.


      • You also mention in your book to wait 12 hours between each 20-40 min massage to heal the inflammation, correct? What happens if you massage too much constantly?

      • Hey Ken,

        These questions are answered, in detail, inside the book. They’re a bit tough to answer without also explaining a chapter’s worth of material – how to do the massages correctly, what other mechanical stimulation exercises are effective, how to evenly space and rotate massage locations as to maximize the time between wounding-healing, etc. In short – you want to avoid over-massaging at all costs, and instead find the balancing point between inflammation generation and healing.

        I’d provide more details if I could, but out of respect for readers who’ve financially supported the site, I don’t feel comfortable as doing so undermines their purchases (where the information is found). If you do end up grabbing the book someday, shoot me an email and we can build a protocol catered toward your lifestyle and comfortability.

  10. Hey Rob, this feels promising.
    I ran across your website when i was searching for treating MPB without drugs.
    I am 25 and experiencing rapid miniaturisation all over my scalp. I feel i still have time to go bald entirely, should i wait till then or should i start with these massages by going ahead and buying your book?


    • Hey Vicky, thanks for reaching out. When it comes to treating hair loss, it’s best to act sooner than later – the reason being that hair loss tends to be progressive, and miniaturizing hairs are easier to recover than completely dormant (visibly disappeared) hair follicles. Regardless of your treatment choice – whether it be the methods inside the book, low-level laser therapy, PRP, or something else – I recommend not waiting until you’re bald to start any therapy.

      I wish you the best of luck with your recovery and please keep in touch (email is in the book if you have questions).

      • Hi Rob,

        I have severe vitamin-d defiency, 21nmol (European standards).
        The thing is I live at the 57 north latitude, Scandinavia. So dark winters for 6 months every year.
        I also work in a office all day.
        To make it worst the weather is almost foggy and rainy all year around.

        I don’t really want to take supplements.

        So how much eel, wild salmon and sea bass, which has the highest amount of natural d-vitamin content in any food source, would I need to eat on a regualry basis to get much higher vitamin-d levels?
        If I understand correctly the hormon stays in your body for a couple of days right?

      • Hey James,

        There are delays in the consumption, metabolism, and excretion of vitamin D. There was a study done on Turkish communities that showed fluctuations in serum 25(OH)D levels from summer to winter, with vitamin D “reserves” being utilized in late winter months and serum levels falling dramatically. In short, you might find some benefit in “loading” vitamin D when the weather is nice – especially in anticipation of times when the weather is poor.

        The amount of wild salmon, sea bass, etc. required to maintain healthy vitamin D levels varies too greatly to comment with accuracy. Animals, just like humans, have varying degrees of vitamin D. And we have varying degrees to process that animal-derived vitamin D. So it’s tough to give you an answer here.

        What I will say is that you might be one of the cases that would benefit from supplementation. It sounds like the environment you live in doesn’t provide ample opportunity for vitamin D loading. You can try wild salmon and other foods high in vitamin D. But in your case, I don’t think it’d hurt to supplement – so long as you supplement safely (as suggested in the article).


  11. Hey Rob

    I have a few problems with sun-derived vitamin D. First something about skin.

    By the way, if you feel like extending your scope at some point, I might suggest researching how to repair damage done by side effects from minoxidil, finasteride, etc. I ended up on your site after having had sides from both of those products, and I’m sure I’m not the only one with that story here.

    Minoxidil has affected my face. Long before I had even heard of the sides I went without minox for a period (can’t remember if I was out of money or what) and during that time I was astonished to notice that the lines in my face, that I had thought were signs of aging, had almost vanished. Even when the lines eventually returned after I continued minox the connection didn’t occur to me, until I read about it.
    And by that time I had already quit finasteride for sides, ending up losing lots of hair. So it was a choice between hair and face, but I couldn’t know what the end results would look like in comparison, of course… so I chose to stick with minox for the time being.
    I’m now well into middle age so I guess I’ll never be able to tell how much my face would have aged without, as opposed to with, minoxidil. In my life I’ve often been mistaken to be much younger than I am, but I doubt if it’s so by now…

    Sunlight is said to age the skin. Here http://www.prevention.com/beauty/skin-care/how-get-younger-looking-skin it says “nothing is more important than wearing sunscreen every day if you want younger-looking skin”.
    So, sun exposure is a bit of an iffy subject for me, and your “If You Want To Raise Vitamin D Levels With Sunlight, Avoid Sunscreens” makes me want to focus on the “if”.

    You seem to stress the importance of sunlight as a source of vitamin D. I live in Finland where you get high sunlight only for short periods during the summer, and none for most of the year.
    In your book you say “We can also find vitamin D in food sources like dairy or in supplements, but the best way to receive vitamin D is naturally”, but you never explain why food-derived D is so unnatural. I eat mackerel, sardines, cod liver and lots of eggs weekly, all of these are supposed to be sources of vitamin D. Do you think I should still supplement on top of these (if I can’t or don’t want to get lots of sun exposure)?

    • Hey David,

      Thanks for your comment. Your anecdote about minoxidil possibly increasing your aging isn’t out-of-scope. Minoxidil has been shown to increase PGE2, which some studies suggest is associated with skin aging. There’s a discussion about it in the comments section of this article:

      Why Most Hair Loss Drugs Are So Ineffective

      In terms of sunlight exposure aging our skin, this is a harder question to answer. There’s some research suggesting that sunlight may contribute to skin aging, but that it’s the ratio of UVA/UVB radiation exposure that matters most. UVA penetrates through glass and is present during most hours when the sun is up. UVB is present less frequently — when the sun is at its peak during the summer time, between the hours of 10am and 3pm.

      In the cases I’ve seen where sun exposure has lead to a dramatic difference in skin aging, these cases have all been people who worked in an office next to sun-facing glass windows, or truck drivers who spent years driving with the sun shining through their window glass. The relationship here: no UVB exposure, and lots of UVA exposure. Just look at this photo of this trucker:


      Sunscreen companies clearly took to the opportunity to make this man a symbol of the importance of sunscreen, but this really is misconstruing the reality of the situation. Why? Because look at Laird Hamilton, a Hawaiian-raised, white, professional surfer — who never wears sunscreen and is 53 years old:


      You can also look into photos of indigenous peoples in the South Americas who also have never worn sunscreen. Many of them have near-flawless-looking skin, even into old age.

      So in short, the sunlight-aging connection is more complicated than sunscreen companies actually make it seem. And the benefits of (healthy) sunlight exposure appear to far outweigh the potential for skin aging — especially in regards to cancer and disease prevention.

      I can’t comment on whether you should try supplementation. It depends on hundreds of factors — including how much other fat-soluble vitamins you’re absorbing. I’d recommend first finding out if you’re vitamin D deficient on your current diet. And if that’s the case, then maybe consider a supplement if sunlight exposure is not an option.


  12. Thanks Rob – but I’m not David 😉

    I really appreciate your info on UVA/UVB, all new to me. I’ll take this into consideration.
    (However I checked some more pics of Hamilton and he doesn’t always look quite so young to me… http://beachgrit.com/wp-content/uploads/2015/02/Laird.jpg )

    Actually I already bought Vitamin D pills, because I’d been very tired recently, anyway… So I’ll see if I get more energetic within some weeks. If I do, I could then quit them and see if they made a difference, or something…

  13. For vitamin D it is always advisable to expose to the solar peak because on the one hand there is less UVA rays on the one hand and on the other we are sure that the spectrum of erythema is always lower than the spectrum of vitamin D.
    sorry for my English

  14. Hey Rob,
    I just got my blood test done and I am severely deficient in Vitamin D , Vitamin B12 and thyroid stimulating hormone is at 1.38 . So I guess I have quite similar condition like Jared. I was thinking my recent hair fall was due to use of rosemary ; but it turns out it is due to vit D.
    I wanted to ask did Jared went for gluten free? I mean I love grains and milk especially. Though I can cut grains, missing milk makes me anxious. I read in your blog somewhere about it..so I am now gluten free(though not completely) for 3 months.
    So I have these questions for you:
    1. How important do you think is cutting down diary like cow milk for hair growth. Also gains.
    2. Do you think arresting vitamin D deficiency can help me to regrow hair?
    3. Also what is your opinion on B12 deficiency and thyroid state.

    Thank you in advance

    • Hey Adi,

      Jared went gluten-free. Before you take a vitamin D supplement, please check your blood calcium levels and PTH to rule out the possibility of hyperparathyroidism. Only then should we consider vitamin D or B12 supplementation.

      In terms of milk, it all depends on the individual. Some people do great with dairy! I’m not one of them. I’d recommend a substitution test. Try cutting out milk + gluten for a few months, and see how you feel.


  15. Hi Rob,
    Really value your view on my condition. I tested my calcium levels and they are at 9.52 mg/dl . So I guess that’s normal. And I have less idea about PTH test ; but I have done thyroid test and I am normal. I recently consulted a dermatologist about vitamin D supplementation , and he prescribed me 60000 iu vitamin D .And when I asked about role of vitamin A and vit K , he told not needed. So I still have these doubts.
    1. As my calcium and thyroid state is normal, would you suggest me to do PTH test or I am good to start vitamin D and Vitamin B12 supplementation.
    2 . And while supplementing with vitamin D , how do I ensure I get enough vitamin A and vit K .
    3. Also any other thing I need to be careful about or take into account for better results.
    Thank you for being so helpful throughout.

    • Hi Adi — that’s good news re: calcium levels. In this case, you probably don’t need PTH testing, and vitamin D supplementation is probably fine. I’d recommend trying to increase your vitamin A and K2 intake by eating more meats — specifically organ meats like liver — alongside supplementing with vitamin D. And keep us posted with how you progress!


  16. Hi Rob,

    I am 17 and I am suffering from hair loss since 1 year as I don’t what was the cause…After consulting doctor…He prescribed me minoxidil 5%… I used it and there is no regrowth and hair loss is still being even after using it for 8 months . Then I stopped using it and went to calcium and vitamin D test.I found my calcium level normal but my Vitamin d ( d2 and d3) were jus 6. It was a serious deficiency..My doctor prescribed me 60,000 IU vitamin D tabs. He asked me to take these tabs 15 days once. And i did as he said…Still my hair is falling…And i started to eat vitamin D rich foods and spending little time at sunlight . But still my hair is falling. But there is also a another point to say about me… I have hyperinsulinemia . My levels are 435 for insulin (pp)

    • Hey Arjun,

      Insulin resistance, metabolic syndrome, and hair loss are all associated with one another because of each condition (or symptom) is related to chronic, systemic inflammation. Addressing your vitamin D deficiency may help, but if you’re supplementing with that much vitamin D, you should also supplement with vitamin K2, A, and any other vitamin D adjunct. See if your levels rise over the next few weeks, and then retest. If they’re still low, that would suggest something else is going on — potentially hyperparathyroidism (in which case you should test PTH and TSH alongside retesting calcium and vitamin D).


  17. Thanks Rob. But I have read in many websites including wiki that a vitamin D deficiency would cause hyperparathyroidism. So would it be a problem if I try taking vitamin D supplements for a month and see if my vitamin D levels rise ? Actually, I consulted a doctor right after my vitamin D test and started taking 2000 iu per day and am also getting a lot of sunshine. Anyway i will do a test soon for thyroid as well as vitamin D. Thank you. And by the way, did Jared actually face male pattern baldness ? it seems like diffused thinning to me. Not an expert just a doubt 🙂

    • Hey Neo,

      In this scenario, I think it’s better to test versus guess. Those biomarkers (PTH, TSH, calcium, vitamin D) should give you an indication of whether you have primary or secondary hyperparathyroidism, or no hyperparathyroidism at all. Only with that data should you consider supplementation.

      In terms of Jared’s hair loss — he considers it AGA, but there’s always the possibility that it could be telogen effluvium.


  18. Hy Rob,
    I am suffering from hair loss from past 1.5 years. Initially it started with hair thinning and then it went. It
    Has most affected my frontal part this area is got less denser, yesterday I got my vitamin D checked up and it is only 9.5 ng/ml, which is quite low of minimum requirement of 30 ng/ml. Now what should I do to grow back my hair do I still need to look for dht blocker like finasteride (I have not yet started consuming it) is there any connection of vitamin D and DHT. What should be the ideal treatment
    Thank you in advance Rob

    • Hi Suyash,

      I’d first recommend reading through the comments of this article, since your case is similar to others with low vitamin D. The first thing you should consider is ruling out hyperparathyroidism. The second is treating the vitamin D deficiency. And the third is to understand the risks and benefits of a DHT reducer like finasteride, and then evaluate whether you want to take one for the rest of your life. There are a lot of articles on this site that should help you get started.


  19. Rob, your work is awesome mate, you are a legend for doing all this. Your insights and dedication to the science and replying to the community is outstanding. Huge respect and thanks.

    I started the head massages about 4 months a go…no results as of yet but gonna be patient. I am not being a disciplined with the removal of grains as I’d like (beer just tastes too good!) but i’m gonna make more of an effort and be prepared to be extra patient with results due to this. Being a vegetarian makes it hard to get protein when your cutting our the legumes. Ive been using hemp powder protein but I guess this falls under the bastard gain category too… not sure how to address this really…

    I also just took a temperature test of my mouth and surprise surprise it’s too low (96.4) so gonna book in a doctors test to check for thyroid issues, and then follow that with vit D one too. Thanks again!

  20. Hello Rob, I have gone through the whole article which was very educating . I would say the work is amazing yet in modest manner.
    Actually i’m suffering from excessive hair loss form the past 4 years. Just 2 years earlier my problem was diagnosed to be of low thyroid(hypothyroidism ) and low vitamin D level(less than 16). I have been taking thyroid medication from past 9 months. nearly 50% of my hair is growing. but still my hair is very coarse and dry,brittle and often huge amount falls in between. In between doctor gave me Vit. D -60K , once in a week. I’m not taking it now.
    Kindly guide me regarding my hair loss and recovery from it.
    Thanks a lot

  21. Hey, I have been losing hair from age of 18 and now at 20 my hair on the front became thin and sometimes in bright light my scalp is a little visible and also my crown hair is also thinning. I have a low vitamin D of 16 ng/mL. Also I did not really took care of my hair and my father, grandfather had full hair same with my maternal grandfather.

  22. Hello Mr Rob. I am Dimitris . My last blood tests are…
    Zinc 98.6 (50-120)
    D3 31 (30-90)
    B12 375 (211-911)
    Ferritin 65,6 (30-400)
    TSH 1,87 (0,35-4,8)(last year was 4,6)
    Folic acid 11,4 (3-19,9)
    Do you see something wrong? Where can I send you photo?

    • Hey Dimitris,

      Legally, I can’t interpret these lab results for you (as I’m not a medical professional, and even if I were, there are limitations of online interpretations depending on someone’s place of residence). In addition, interpreting someone’s lab results are all context-specific, and with limited information, we run the risk of making false interpretations.

      A perfect example of this is low vitamin D levels, which can be low due to (1) low sunlight exposure, or (2) a parathyroid tumor (which is relatively rare). If the former, the right approach is just to get more sun or supplement with vitamin D. If the latter, vitamin D supplementation might actually worsen your health.

      It seems like all of your results are in-range. Despite borderline low vitamin D3, these ranges here can’t be applied to all people. For instance, the darker someone’s skin, the more likely they are to have lower vitamin D, but this doesn’t always correlate to symptoms of a deficiency.


  23. I checked my vitamin D level last year in April and it was 25, which makes sense because I had not been getting any sunlight. Anyway I started taking 5000iu of vitamin D3 every day for 3 to 4 months and then I later learned that you need K2 as well, so I started taking it with K2 and now it’s been 5 months since I added the K2. 4 months without 5 months with K2. Do you think my hair is going to grow back? I have hair loss around the crown. My hairline is still intact.


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