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Can Vitamin D Deficiency Cause Hair Loss?

Written by Dr. Michael Ruscio, DC on July 19, 2023

Written by Dr. Michael Ruscio, DC on July 19, 2023 — Reviewed by Aimee Gallo

One of Vitamin D’s Lesser Known Uses Could Be Healthier Hair

• A Quick Take|
• Types of Alopecia|
• Vitamin D and Alopecia Areata|
• Vitamin D and Androgenetic Alopecia|
• How Vitamin D Might Help Hair|
• Vitamin D, Hair Loss and Hypothyroidism|
• How to Increase Vitamin D|
• Does Vitamin D Treat Existing Hair Loss?|
• Other Ways to Help Hair Loss|
• Vitamin D Is a Factor in Hair Health|

Losing your hair is more than just a physical problem: it can be emotionally distressing and leave you feeling insecure about your appearance. 

Aging, hormones, stress, and inflammation are all factors that contribute to hair loss or a receding hairline. However, your nutrient status, including whether you have sufficient levels of vitamin D, is also thought to have a bearing on hair health.

Can vitamin D deficiency cause hair loss is the specific question we’re going to consider in this article. But we’ll also look at the topic within the wider context of diet and lifestyle tips for healthier hair, plus why preventable hair loss might occur. 

Let’s delve into the issue and come up with some answers.

Can Vitamin D Deficiency Cause Hair Loss? A Quick Take

The short(ish) answer is that it’s not clear whether a dietary vitamin D deficiency directly causes hair loss [1, 2, 3, 4, 5]. 

However, from a handful of correlation studies we know that men and women with alopecia areata (an autoimmune condition that causes hair fall), and women with female-pattern hair loss, tend to have lower vitamin D and/or a greater likelihood of vitamin D  than people without hair loss [1, 2, 3, 4, 5]. 

We also know that topically applied vitamin D and certain phototherapies (using UV light/sunlight) can improve some types of hair loss.

This points to a lack of vitamin D definitely having a link with hair loss. However we’re not sure as to the nature of the association (i.e. whether vitamin D deficiency is a direct cause of hair loss), nor whether low vitamin D precedes alopecia or vice versa [1].

Types of Alopecia

Before going into more depth on the possible role of vitamin D in hair loss, let’s briefly identify the common types of hair loss, known medically as alopecia [6]. 

• Androgenetic alopecia (also known as male-pattern baldness or female-pattern hair loss) is the commonest type of hair loss. In men, with this type of hair loss. hair recedes from the temples, but in women, androgenetic alopecia begins with gradual thinning at the part line, followed by more diffuse hair loss over the head. 
• Alopecia areata accounts for nearly a fifth of hair loss causes in men and women globally [6] and is caused by an autoimmune attack on the hair follicles.

• Telogen effluvium is a type of hair loss that occurs when too many hairs move into a “resting phase” within the hair growth cycle. This means that there is more hair shedding than hair regrowth. It usually occurs as a result of physical or psychological trauma.
• Scarring alopecias occur when hair follicles are destroyed and replaced with scar tissue. Again this type of alopecia is often due to autoimmunity — the body’s immune system turning on itself. Different types include lichen planopilaris and folliculitis decalvans. 

The types of hair loss from the above list that are most likely impacted by vitamin D are androgenetic alopecia and alopecia areata.

Vitamin D and Alopecia Areata

From a handful of meta-analysis studies, we know that vitamin D levels tend to be lower in autoimmune-related hair loss conditions like alopecia areata than they are in healthy individuals without hair loss. In one of these meta-analyses [2]:

• People with alopecia areata were almost 5 times more likely to have vitamin D deficiency. 
• About two-thirds (65.4%) of alopecia areata patients were low in vitamin D.

Though we can’t infer any cause/effect relationship between vitamin D and alopecia areata, the correlation is an interesting one. 

In any case, it’s always good to take action if your vitamin D level is low (more practical tips on this later).

Vitamin D and Androgenetic Alopecia

A couple of small studies have also shown a clear correlation between the incidence of female-pattern hair loss and lower vitamin D levels. In one of these [4]:

• Vitamin D and ferritin (a form of stored iron) were both significantly lower in women with hair loss than in controls. 
• As hair loss worsened, vitamin D (and ferritin) levels dropped even more. 

This suggests that low vitamin D may contribute to female-pattern hair loss in some way. 

However, vitamin D appears to play no role in male-pattern baldness, at least from the data that exists to date [7].

How Vitamin D Might Help Hair

There are a couple of potential mechanisms by which vitamin D could encourage healthy hair growth (and, conversely, how a vitamin D deficiency may cause hair loss).

One proposed mechanism relates to how much vitamin D there is available to plug into vitamin D receptors in the hair follicle. This action is thought to stimulate new hair growth, so if there is a scarcity of vitamin D, some of those receptors could be left high and dry, failing to promote new hair growth [4, 5].

In the case of autoimmune-related hair loss, vitamin D regulates the immune system and may help us tolerate potential self-antigens better [1, 2, 3]. On the other hand, low vitamin D levels may make room for the immune dysregulation that precedes autoimmune disease.

Vitamin D, Hair Loss, and Hypothyroidism

Research suggests that vitamin D deficiency, hair loss, and poor thyroid health may be quite closely interrelated. Consider these facts:

• About 30% of patients who have hypothyroidism also experience hair loss [8]. 
• Vitamin D deficiency is common in both alopecia areata [1, 2, 3, 4, 5] and hypothyroidism [9, 10, 11].
• Alopecia areata patients also often have thyroid antibodies [12] and poor thyroid health [13, 14]

The common link here is autoimmunity, i.e. the tendency for the immune system to overreact, which can show itself in an attack on both the thyroid gland (Hashimoto’s hypothyroidism) and on the hair follicles (alopecia areata).

Though, the research isn’t there to prove it yet, optimizing your vitamin D levels may give your immune system and hair follicles the extra support they need to help avoid hair loss and thyroid problems.

Resolving vitamin D deficiency is one of the steps I recommend as part of an overall self-help program to tackle hypothyroidism. Optimizing vitamin D has certainly been useful for many of my patients who have hypothyroid symptoms, including thinning hair. Increasing vitamin D levels is also a fairly simple thing to do for most people.

How to Increase Vitamin D

I’m not a fan of doing lots of blood tests for no reason, but getting your vitamin D levels tested is advisable as it is usually simple, not very expensive, and will immediately tell you whether or not you need to take vitamin D supplements or spend more time in the sun.

Keeping your vitamin D levels at 30–50 ng/ml [15] will benefit your whole body, including your immune system, bones, muscles, thyroid [1, 2, 3, 16, 17, 18] and hair health [4, 5].

If your vitamin D test results indicate levels on the low side you’ll likely benefit from taking a vitamin D3 supplement in a dosage somewhere between 600 and 4000 ius per day (more than 4000 iu is not generally recommended) [19]. You can also get vitamin D by eating more egg yolks and omega 3-rich fatty fish such as salmon and mackerel, which is also a useful anti-inflammatory food.

Calculators such as this one are useful to estimate your recommended vitamin D dosage as they take into account your body weight, your current level of vitamin D, and the level you want to achieve. 

Remember that sunlight is also a good source of vitamin D, and excessive use of sunscreen because of skin cancer concerns is likely a big contributor to chronically low levels of vitamin D among the population.

Of course, it is important to protect yourself from sunburn and sun damage, but on sunny summer days, you may need only around 3–15 minutes of sun exposure (with bare arms, face, and neck) to make the equivalent of 1000 IU vitamin D [20, 21]. 

However, season, latitude, and skin pigmentation all affect vitamin D synthesis in skin. In latitudes above 40 degrees north (Boson is 42 degrees North) you can safely assume you will be making no vitamin D from sun exposure between October and April. In this case, vitamin D supplements become more important.

Does Vitamin D Treat Existing Hair Loss?

We don’t know if oral vitamin D can treat existing hair loss or not as to date there is no research on this topic.

However, a few studies have looked at topically applied vitamin D and UV therapy and found both of these to be useful in treating hair loss. 

In one study, that used either synthetic vitamin D ointment, UVB phototherapy (which stimulates the production of vitamin D by the skin ), or both of these treatments together, the severity of alopecia areata significantly improved in all cases, compared with placebo.

Other Ways to Help Hair Loss

While vitamin D may play an important role in treating some cases of hair loss, it’s not the only nutrient linked with healthy hair.

Other vitamin deficiencies that have been related to hair loss include riboflavin, biotin, folate, and vitamin B12 [22]. Low levels of the minerals iodine and iron can also cause hair loss, as well as symptoms such as brain fog and fatigue

Making Diet Improvements

Improving your diet will help to ensure you don’t have the nutrient deficiencies that can contribute to hair loss. 

Eating foods that are gut-healthy and anti-inflammatory will also help you maintain a healthy head of hair. They can help improve a dysregulated immune system [23], thereby reducing the chance of autoimmune-related hair loss.

I don’t make rigid recommendations to my patient about what type of anti-inflammatory /gut-healthy diet to try, but many of my patients have good results with either the Mediterranean diet or a Paleo-style diet, supplemented with a few different strains of probiotics to give an extra boost to gut health.

For example, my patient Ana turned around symptoms that included hair loss, bloating, and fatigue with the Paleo diet, probiotics, and by following the protocol in Healthy Gut, Healthy You.

If you aren’t ready for a complete overhaul just yet, any move towards a less processed diet will be good for your hair. It should include plenty of quality protein such as fish and some red meat, which is a good source of iron, as well as plenty of vegetables, nuts and seeds. It may have varying amounts of whole grains and dairy depending on your tolerances and preferences.

Managing Stress

Stress is linked with some types of hair loss including alopecia areata and telogen effluvium. 

From animal studies we know that stress hormones may impair stem cells necessary for hair growth [24]. 

Reducing stress, as much as you practically can, will therefore help protect your hair. If you’ve been through traumatic experiences that are causing residual stress, it can be really helpful to work with a therapist.

Otherwise, some more generally helpful stress-busting techniques include.

• Relaxing with meditation, deep breathing, or yoga
• Doing some regular exercise, especially outside in nature [25]
• Spending time with family and friends who can support you both physically and emotionally [25, 26] 

If your hair loss doesn’t turn around within a few months, it’s worth getting medical advice, or seeing a trusted functional health practitioner to investigate potential underlying causes. 

Vitamin D Is a Factor in Hair Health

Whether your hair loss is related to vitamin D or not, making sure you get enough of this vitamin is vital for many aspects of health so it’s a no-brainer to keep your levels optimal.

But vitamin D isn’t the only thing to look at if you have hair loss — a gut-healthy anti-inflammatory diet, in general, will help to provide the nutrients you need to protect against hair loss, as well as keep your immune system healthy so you’re less likely to develop autoimmune forms of alopecia.

You can get more help for any concerns you might have around hair thinning, gut health, or indeed any other health issues by reaching out to us at the Ruscio Institute of Functional Health.

The Ruscio Institute has developed a range of high-quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.