Can Vitamin D Deficiency Cause Hair Loss

Ever run your fingers through your hair and notice more strands than usual? If you're a male, you might blame stress, genetics, or even your shampoo. However, there may be another factor you haven't considered: vitamin D deficiency. 

Yes, the same "sunshine vitamin," which is excellent for bone and immune health, also plays a role in your hair biology. And it's not just a wellness buzzword – there's growing scientific evidence that links low vitamin D levels to various types of hair loss in men, including the dreaded male pattern baldness. 

This is particularly concerning because vitamin D deficiency is more common in men. Don't believe us, believe the stats:

• Over 1 billion people have insufficient vitamin D levels, and men are not exempt.

• Research shows that men are more likely to have lower levels than women

• In one U.S. study, over 40% of men were found to be vitamin D deficient.

So, can vitamin D deficiency cause hair loss? This article will help you explore how this essential vitamin ties into hair biology and what you can do about it.

Understanding Vitamin D & Hair Biology

Vitamin D is known as the "sunshine vitamin" because your skin produces it when exposed to sunlight, specifically, UVB rays. However, it also comes from:

• Dietary sources (e.g., fatty fish, eggs, fortified milk)

• Supplements

Once produced or consumed, vitamin D is first converted in the liver to 25-hydroxyvitamin D [25(OH)D], the form used to measure your vitamin D status. 

Then, it's converted in the kidneys (and some other tissues) to the active form called calcitriol (1,25-dihydroxyvitamin D).

The Vitamin D Receptor (VDR): The Key to Hair Growth

Calcitriol binds to Vitamin D Receptors (VDRs) found in various tissues, including hair follicles. This receptor plays a crucial role in transitioning your hair from the resting phase (telogen) to the growth phase (anagen).

Animal studies provide some of the strongest clues. In VDR knockout mice (genetically modified mice that lack the VDR), researchers observed that they failed to regrow hair after it was shaved, despite being born with hair. 

This suggests that VDR is essential for hair follicle regeneration.

Men-Specific Hair Loss Patterns & Vitamin D

Hair loss in men is common; however, the causes and patterns vary. The three most common types that men experience include:

• Androgenetic Alopecia (AGA): Often called male pattern baldness, this is the most prevalent form of hair loss in men. It typically starts with a receding hairline and thinning at the crown. AGA is largely genetic and linked to sensitivity to a hormone called dihydrotestosterone (DHT), which causes hair follicles to shrink over time.

• Telogen Effluvium: This form of hair loss typically occurs suddenly and results in excessive shedding. It can be triggered by physical or emotional stress, illness, surgery, or nutritional deficiencies, including low vitamin D. Unlike AGA, this type is often temporary, especially if the underlying cause is addressed.

• Alopecia Areata: This is an autoimmune condition in which the immune system mistakenly attacks hair follicles, resulting in patchy, round bald spots. It can affect men of all ages and may be linked to immune dysregulation influenced by vitamin D levels.

What the Studies Say

A growing number of case-control studies have found that men with these types of hair loss tend to have lower vitamin D levels than those without.

A study published in the International Journal of Research in Dermatology found that men with AGA had 56% lower vitamin D levels compared to controls. Another study showed a direct correlation between AGA severity and lower vitamin D levels.

In simple terms, the more advanced the hair loss, the lower the vitamin D levels tended to be. Check out the table below that compares average vitamin D levels with AGA severity in men:

Scientific Evidence

Many systematic reviews confirm a consistent trend: men with different hair loss conditions, especially telogen effluvium (TE) and alopecia areata (AA), have lower levels of vitamin D than those without hair loss. 

For instance, one large review found that more than 70% of individuals with alopecia areata had insufficient or deficient vitamin D levels. 

RCTs & Case Reports

If you experience any of these conditions, fret not, as various randomized controlled trials and case reports show promising outcomes.

In a 2022 case report, researchers administered a high-dose vitamin D supplement to men with telogen effluvium, specifically 50,000 IU once a week for 8 weeks. 

By the end of the treatment, most participants experienced a noticeable reduction in hair shedding and an improvement in hair texture. This suggests vitamin D may help reset the growth cycle.

For alopecia areata, several randomized controlled trials (RCTs) are ongoing. Early reports suggest that vitamin D supplementation may help stabilize the immune response and support hair regrowth in patchy baldness.

Moreover, various observational studies also show that it's not just vitamin D levels that matter, but also how well your body uses it. 

Men with low VDR activity in their hair follicles often experience slower or incomplete hair regrowth, even if their vitamin D levels are technically within the normal range.

Who's at Risk? (Focus on Men)

When it comes to vitamin D deficiency and hair loss, certain men are at a higher risk than others. Numerous biological and lifestyle factors make men vulnerable to low vitamin D, and in turn, the hair issues that may come with it.

Here are a few risk factors you should know:

• Indoor jobs: Many men spend most of their day indoors, especially if they work in offices, drive for a living, or spend their leisure time inside. Since sunlight is the primary source of vitamin D, limited sun exposure means your body doesn't produce enough.

• Higher melanin levels: Men with darker skin tones (more melanin) are also at greater risk. Melanin naturally blocks UVB rays, which your skin needs to produce vitamin D. That means even if you spend time in the sun, your body may still make less vitamin D.

• Obesity: Obesity is another key factor. Vitamin D is fat-soluble, meaning it can get stored in fat tissue and become less available for the rest of your body. Men with higher BMIs may have lower active levels of this crucial vitamin.

• Age: As men age, the skin's ability to synthesize vitamin D decreases, adding to the risk.

Lifestyle Contributors for Men

Certain lifestyle habits can also make men more prone to hair loss linked to vitamin D deficiency. 

Many men are less likely to take daily supplements, which means they may go years without correcting low vitamin D levels. Popular grooming trends, such as buzz cuts or shaving, can also make it harder to notice early signs of thinning or shedding, delaying treatment.

Another key factor is testosterone and DHT (dihydrotestosterone). Men naturally have higher levels of these hormones, which are known to fuel androgenetic alopecia (male pattern baldness). 

When combined with low vitamin D receptor (VDR) activity, the risk of hair loss can be even greater. This makes managing vitamin D levels especially important for men concerned about hair health.

Diagnosing Vitamin D-Related Hair Loss

If you're a man noticing more hair in the shower drain or a thinning hairline, it's worth checking your vitamin D levels.

The most accurate way to diagnose a deficiency is through a 25-hydroxyvitamin D blood test, often written as 25(OH)D on lab reports. This test measures the stored form of vitamin D in your blood, providing a clear picture of your vitamin D status.

Check out the 'Vitamin D status categories’ table below to understand what the levels mean:

Note: Doctors may consider treatment if levels are under 30 ng/mL and you show signs of hair thinning.

Treatment & Supplementation Strategy

If your vitamin D levels are low and you're noticing hair thinning or shedding, don't worry; there are several ways to boost your levels and support hair health, such as:

Sun Exposure: Your Free Vitamin D Source

Spending time outdoors is the most natural way to make vitamin D. Your skin produces it when exposed to sunlight; however, most men today spend their days indoors under artificial lights.

Here are a few tips to increase sun exposure:

• Aim for 15–30 minutes of direct sun on your face, arms, or legs at least 2–3 times a week.

• The best time is mid-morning or early afternoon, when UVB rays are strongest.

• Skip sunscreen during those 15 minutes (then apply it to protect your skin).

In winter or cloudy climates, you may need to rely more on food and supplements.

Dietary Sources & Fortified Foods

If the sun isn't enough, your diet can help fill in the gaps. While few foods are naturally rich in vitamin D, these are some of the best options:

• Oily fish – salmon, sardines, mackerel, and tuna

• UV-exposed mushrooms –  maitake and portobello

• Fortified foods – milk, orange juice, breakfast cereals, and plant-based milks

These can help you maintain healthy levels, especially when combined with moderate sun exposure.

Supplementation: How Much to Take

There are two main approaches to supplements, and the one you choose depends on your blood test results.

• Conservative Dosing (Safe for Daily Use): If your levels are slightly low or you want to maintain them, 1,000–2,000 IU per day is generally safe and effective.

• Therapeutic High Dosing (For Deficiency): If your levels are increasingly low, you may take 50,000 IU once a week for 8 weeks (only under doctor supervision). This should be followed by a maintenance dose of 1,000–2,000 IU of vitamin D daily. 

Note: Although Vitamin D toxicity is rare, too much can raise calcium levels, which may lead to nausea, weakness, or kidney issues. So, always check calcium levels and re-test your vitamin D after 2–3 months of high dosing.

To better understand it, here's the suggested regimen with a monitoring schedule: 

Holistic Perspective on Hair Loss

Believe it or not, Vitamin D doesn't work in isolation. Your body needs a team of nutrients and lifestyle habits to keep those hair follicles functioning at their best.

Listed below are a few other vitamins and minerals that work alongside vitamin D to support healthy hair:

• Iron: This is crucial for transporting oxygen to your hair follicles. If your ferritin (iron storage) levels are low, your body may pause hair regrowth, which may lead to thinning.

• Zinc & B12: These are essential for DNA production and cell turnover, which happens rapidly in hair follicles.

• Selenium: It helps protect hair cells from oxidative stress and supports thyroid function, which also affects hair growth.

If you're low on any of these, your hair may struggle, even if your vitamin D levels are fine. Like vitamins and minerals, your daily habits can either help or hurt your hair health, such as:

• Stress: High cortisol levels from chronic stress can prematurely push your hair out of the growth phase.

• Sleep: Deep, restorative sleep helps regulate the hormones that control your hair cycle.

• Exercise: Workouts and exercise help increase blood flow to your scalp, bringing nutrients and oxygen where they're needed.

• Grooming: Daily heat styling, harsh shampoos, or tight hairstyles can weaken hair and damage follicles. Be gentle!

• DHT Management: DHT is a hormone linked to male pattern baldness. If you suspect hormonal imbalances, consult a doctor or dermatologist, especially if you're experiencing rapid hair loss.

Remember, a holistic approach not only treats symptoms, it builds a healthy foundation from the inside out.

Prevention & Long-Term Maintenance

Want to protect your hair over the long run? Follow this step-by-step plan:

• Get tested: Start with a 25-hydroxyvitamin D blood test. This provides a clear baseline of your vitamin D levels and helps determine if a supplement is necessary.

• Tweak your lifestyle: Small daily habits make a big difference. Aim for 10–30 minutes of sunlight exposure (depending on your skin tone), add more vitamin D-rich foods like salmon or fortified milk to your meals, and prioritize restful sleep.

• Start a supplement: If your levels are low, consider taking a daily vitamin D3 supplement (1,000–2,000 IU/day), or follow a doctor's advice for a higher dose.

• Track your progress: Hair doesn't change overnight. Take monthly photos to visually monitor changes, and consider using hair density apps or visiting a dermatologist every few months to measure real results.

• Retest regularly: Check your vitamin D levels every 3–6 months. If your levels improve and hair loss slows, you're on the right track. If not, you may need to adjust your approach.

Bonus Tip: Try Spartan Hair Products – a line tailored for male hair loss. With ingredients such as biotin, caffeine, and vitamin D-enriched scalp serums, as well as other products, they support both hair strength and scalp health.

Common FAQs

Want to know more about ‘Can a vitamin D deficiency cause hair loss?' Here are frequently asked questions:

Can too much vitamin D cause hair loss?

Not directly. However, vitamin D toxicity can cause calcium imbalance, which could impact overall health and indirectly affect hair.  Therefore, stick to safe dosing ranges.

How long will it take to see results?

Hair grows in cycles. You can typically expect improvements after 3–6 months of consistent supplementation and lifestyle changes.

Should I take vitamin D if I'm already on hair supplementation?

Yes, but check your supplement label to avoid double-dosing. Ensure that your total intake is under 4,000 IU/day, unless advised otherwise.

Is topical vitamin D effective?

There's limited evidence. Unlike topical treatments, oral supplements are better studied, reliable, and easier to dose accurately.

Final Thoughts

While vitamin D plays an important role in hair health, it's not a magic cure for hair loss. 

Instead, think of it as a supportive nutrient, especially if you deal with male pattern baldness, telogen effluvium, or alopecia areata. Low vitamin D can exacerbate these conditions, but correcting it can help stabilize or even improve your hair situation over time.

And before you start taking supplements, it’s always best to talk to a healthcare professional. A simple blood test can tell you where your levels stand and whether supplementation is needed.

Still confused? Here’s what you should do:

• See your GP and request a vitamin D test

• Review your results with a doctor or specialist

• Follow a safe supplementation plan

• Add a hair treatment product, such as Try-Spartan, for a more comprehensive approach

If hair loss persists, consider consulting a dermatologist for a comprehensive evaluation and personalized treatment plan.