Which Vitamin Deficiency Causes Hair Loss? 10 Vitamins Linked to Hair Health

Medically reviewedby Dr. Amy Revene M.B.B.S.
WrittenbyLuat Duong
Last updated

Are you wondering which vitamin deficiency causes hair loss? 

You're not alone. Many people experience thinning or shedding hair due to nutritional gaps. 

Let's delve into how lacking certain vitamins can impact your hair health and what you can do about it.

How vitamin deficiency causes hair loss

which vitamin deficiency causes hair loss

Did you know that lacking certain vitamins can lead to your hair packing up and leaving? It’s true; extensive scientific research has drawn a clear line connecting vitamin deficiencies with hair loss issues like thinning and excessive shedding. Let’s unpack this a bit.

Many studies consistently show lower levels of vitamins D, B12, and other vital micronutrients among individuals experiencing hair loss. 

The real kicker? Replenishing these deficient vitamin levels often leads to a significant improvement in hair density and a reduction in shedding—good news for those of us watching our hairlines with concern.

So, how exactly do these deficiencies mess with our hair? Well, it boils down to the nitty-gritty of how vitamins influence hair follicle function, development, and hair protein production. 

The deficiency impacts can vary by gender, making it a bit more common in men or women, depending on the vitamin. 

Despite the complexities and varying individual impacts, one thing is clear: what you feed your body matters significantly to your hair follicles and overall hair growth cycle.

While some folks might think vitamin deficiencies are the main culprits behind hair loss, the story is a bit more nuanced. 

Sure, not getting enough of certain vitamins can lead to thinning hair, but loading up on too much, like vitamin A, or lacking in iron and protein can also throw your hair a curveball. 

And let’s not forget about rapid weight loss, which can overlap with vitamin deficiencies and lead to hair loss too.

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Which vitamin deficiency causes hair loss?

A lack of essential vitamins like vitamin D, biotin, iron, and zinc can really throw a wrench in your hair game, contributing to thinning and loss. If your hair is falling out and you're also battling other symptoms of vitamin deficiencies, it's probably time to consult a professional.

Here’s a rundown of the key vitamins linked to hair loss:

1. Vitamin D

Have you ever considered that a lack of sunshine could be making your hair sad? It’s true; Vitamin D deficiency is often behind hair that feels more like straw than silk. 

Not just about bone health, Vitamin D plays a crucial role in maintaining healthy hair follicles. When levels dip too low, you might notice not just excessive shedding but also premature graying.

The good news is, that boosting your Vitamin D is pretty straightforward. A simple blood test can confirm if you’re running low, and from there, it’s all about getting back into the sunshine and possibly starting a supplement regimen. 

Most doctors suggest a daily dose of around 2,000 to 4,000 IU, tailored to your specific needs to avoid any risk of toxicity. You can also ramp up your intake with Vitamin D-rich foods like fatty fish or fortified dairy products. 

So, next time the sun’s out, why not give your hair a treat?

2. Vitamin A

Ever feel like your hair’s thinner and you’re shedding more than your pet in spring? It could be a sign you’re short on Vitamin A. 

This vitamin is pivotal not just for good vision and skin but also for keeping your locks thick and lush. Low levels can slow down the regrowth of hair, prolonging the balding process and even contributing to dandruff.

To turn this around, consider increasing your intake of colorful veggies like carrots and sweet potatoes, which are loaded with Vitamin A.

 If you're considering supplements, a chat with your healthcare provider is a must to ensure you get the amount just right—especially important for pregnant women. Remember, a little boost can go a long way in bringing back that full, vibrant head of hair.

3. Vitamin E

If your hair has been feeling dry and lackluster, or you're finding more hair in your brush, a lack of Vitamin E might be to blame. 

This antioxidant-rich vitamin is key for fighting off the oxidative stress that can age your hair prematurely. It’s particularly important for those with conditions like psoriasis or alopecia areata, where hair thinning is common.

Boosting your Vitamin E is easy: munch on some almonds or spinach, or consider a supplement if your diet isn’t cutting it. 

Even applying oils like olive or rosehip directly to your scalp can infuse your hair with a direct shot of vitamin goodness, helping to keep those strands strong and resilient.

4. Vitamin C

Think of Vitamin C as your hair’s best friend. When you’re low on this essential nutrient, your hair might start to split and break more easily. 

Vitamin C not only helps build collagen, a key part of hair structure, but also aids in iron absorption, a mineral vital for hair growth.

To get your levels up, reach for citrus fruits, peppers, and strawberries. And if your diet lacks these foods, a daily supplement could do the trick. 

For those looking to double down on hair health, topical Vitamin C applications can also give your hair an extra boost, ensuring it stays strong and resilient.

5. Folic acid (Vitamin B9)

Folic acid isn't just important during pregnancy—it's also crucial for anyone looking to maintain a full head of hair. 

This vitamin helps with cell growth and division, which includes the cells that make up your hair. When you're low on folic acid, your hair growth can stall, leading to more noticeable hair loss.

The solution? Amp up your intake of leafy greens, citrus fruits, beans, and lentils. These foods are rich in folate and can help kick your hair follicle cells into high gear. 

For an extra boost, consider a daily folic acid supplement—just enough to keep your hair growing thick and healthy.

6. Biotin (Vitamin B7)

Biotin has been a buzzword in hair care circles for a reason—it’s key for keeping hair thick and voluminous. Deficiency might be rare, but if you’re noticing more hair thinning than usual, bumping up your biotin could help. 

This vitamin is a powerhouse for fueling hair growth, helping to metabolize nutrients for scalp and hair health.

You can find biotin in foods like whole grains, eggs, and nuts—easy to add to any meal for a hair health boost. For those who might need a little extra, biotin supplements are readily available and can provide a direct path back to lush, full hair.

7. Zinc

Zinc is the unsung hero of hair health. It's involved in everything from cell growth to hormone regulation—all essential for maintaining strong hair. If you’re not getting enough zinc, your hair might start to shed excessively, leaving you with thinner locks.

To combat this, load up on zinc-rich foods like oysters and pumpkin seeds. If dietary changes aren’t enough, a zinc supplement might be necessary. 

Always consult with a healthcare provider to get the right dose and confirm your deficiency with a blood test.

8. Vitamin B6

Low on Vitamin B6? Your hair might be paying the price. This vitamin is crucial for protein metabolism, which directly impacts hair health. A deficiency can leave your hair weak, brittle, and more likely to fall out.

Boosting your Vitamin B6 intake is as easy as adding more poultry, bananas, and potatoes to your diet. 

For those needing a bit more, supplements can help normalize your levels, ensuring your hair stays healthy and vibrant.

9. Iron

Iron deficiency isn’t just a concern for overall health—it can also cause your hair to thin and shed. Iron helps carry oxygen to your hair follicles, a vital process for hair growth.

If you suspect an iron deficiency, a blood test can confirm your levels. Boosting your iron intake through red meat, spinach, and lentils can help, as can iron supplements under medical supervision. 

Restoring your iron levels can reduce hair shedding and help regain a healthy growth cycle.

10. Essential fatty acids

Last but not least, omega-3 fatty acids are key for maintaining a healthy scalp and lustrous hair. A deficiency in these essential fats can lead to a dry, itchy scalp and brittle hair.

To ensure you’re getting enough omega-3s, include foods like salmon, walnuts, and flaxseeds in your diet. 

For those needing a boost, fish oil supplements are an effective way to raise your omega-3 levels, supporting a healthy scalp and preventing hair damage.

Can too many vitamins cause hair loss?

which vitamin deficiency causes hair loss

Believe it or not, too much of a good thing can be bad, especially when it comes to vitamins and hair health. Let's explore how overdoing certain vitamins and minerals can lead to hair loss.

Vitamin A

It's a bit of a paradox, but yes, the same vitamin A that supports cell growth can also cause your hair to fall out if you get too much. Adults should keep their vitamin A intake below 10,000 international units (IUs) per day to avoid hair loss. 

This level is usually well beyond what you'd find in a balanced diet, so if you're supplementing and notice hair thinning, it might be time to reassess your intake with a healthcare provider.


Selenium, a trace mineral essential for your body, follows a similar pattern. While it can support hair health and even help some people manage hair loss during chemotherapy, an excess can backfire. 

The upper limit for selenium is 400 IUs daily. Exceeding this can lead to hair loss, among other health issues, so moderation is key.

How to find out if you have vitamin deficiencies

which vitamin deficiency causes hair loss

Curious whether you're hitting the mark or missing it with your vitamin intake? Here's the best way to find out:

Consult a Healthcare Provider: Before you start popping pills, chat with a doctor. Over-supplementing can lead to toxic levels of certain vitamins, especially fat-soluble ones like vitamins D, A, K, and E.

Undergo Testing: Your doctor can order tests to check your levels. 

These might include:

  • Blood Tests: A common method that can assess a wide range of nutrients, including your omega-3 status.
  • Saliva and Urine Tests: These can help detect other deficiencies and provide a broader picture of your overall health.

Consider Other Factors: Your nutritional status isn't just about diet. Infections, underlying health conditions, and even stress can affect your vitamin levels. A healthcare provider can help you understand these nuances.

How to treat vitamin deficiency hair loss

Here are some effective ways to treat vitamin deficiency hair loss:

Bio-Pilixin® Activation Serum

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The Bio-Pilixin® Activation Serum is a game-changer for anyone experiencing hair thinning. 

Developed through advanced stem cell technology, this serum is packed with plant growth factors designed to nurture hair follicles and boost hair growth. It stimulates blood flow and delivers essential nutrients right where your hair needs them the most.

In clinical trials, the results have been promising: 77% of users reported reduced hair loss within just 45 days, and 93% saw a reduction in hair loss after 150 days. 

Even more, 73% observed a noticeable increase in hair density by the end of the trial. What's more, many users report seeing less hair fall during showers in just a few weeks.

The serum is drug-free, safe for daily use, and has left 93% of participants satisfied with their results. 

For those unsure about trying it, we offer a 150-day money-back guarantee, giving you plenty of time to see the benefits for yourself.

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Minoxidil is another popular treatment for hair loss, widely recognized for its effectiveness in both men and women

It works by enlarging miniaturized follicles and extending the growth phase of hair, which results in thicker, longer strands and more coverage on the scalp. 

Typically, results can be seen after several months of consistent use, with ongoing application needed to maintain the benefits.


Microneedling is a procedure that involves using fine needles to create tiny punctures in the scalp, which can stimulate hair growth by triggering the body’s natural healing response. 

This treatment is often used in conjunction with topical treatments like minoxidil or serums to enhance absorption and effectiveness. 

Studies suggest that when used regularly, microneedling can significantly improve hair density and strength.

Platelet-rich plasma injections (PRP)

PRP therapy involves injecting platelet-rich plasma obtained from your own blood into the scalp to stimulate hair growth. 

This method leverages growth factors in your blood platelets to promote healing and hair follicle regeneration. 

Many patients see a reduction in hair loss and noticeable growth after several sessions, with the best results appearing after a full course of treatment.


For those with nutritional deficiencies, supplements can be a cornerstone of treatment. Iron, zinc, biotin, and vitamins D and B12 are among the top choices that can help improve hair health when levels are low. 

It’s essential to consult with a healthcare provider to tailor the right supplement plan based on your specific needs and avoid overdosing, which can also lead to hair loss.

Lifestyle changes

Lastly, simple lifestyle changes can make a significant difference in the health of your hair:

  • Be gentle: Use a soft touch when washing and styling your hair. Opt for gentle shampoos and always use conditioner.
  • Reduce heat: Limit the use of blow dryers, straighteners, and curling irons which can exacerbate hair damage.
  • Nutrition: Eating a balanced diet rich in vital nutrients supports hair health from the inside out.
  • Stress management: Chronic stress can impact your hair. Engage in activities that reduce stress.
  • Adequate sleep: Ensuring you get enough sleep is crucial for overall health and by extension, hair health.


In summary, understanding which vitamin deficiencies contribute to hair loss is key to addressing this common issue effectively. 

From vitamins like D, A, and E to essential minerals such as iron and zinc, ensuring you maintain balanced nutrient levels is crucial for hair health. 

Besides vitamins, treatments like Bio-Pilixin® Activation Serum, minoxidil, microneedling, PRP injections, and simple lifestyle adjustments can also significantly help in combating hair thinning and loss.

For those looking for a targeted approach to hair regrowth, consider trying Bio-Pilixin® Activation Serum. Its clinically proven formula, designed to help nourish and rejuvenate your hair follicles, could be the solution you've been searching for.

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  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266123/
  2. https://pubmed.ncbi.nlm.nih.gov/34553483/
  3. https://www.ncbi.nlm.nih.gov/books/NBK279023/
  4. https://www.ncbi.nlm.nih.gov/books/NBK532266/
  5. https://ods.od.nih.gov/factsheets/Biotin-Consumer/
  6. https://doi.org/10.1159/000462981
  7. https://pubmed.ncbi.nlm.nih.gov/20021982/
Luat Duong

Luat Duong is a Copenhagen-based writer and content strategist specializing in hair loss and health. His work has been featured in MyHealthGuide, The Right Hairstyles, and Woman's Era. He is a graduate of Vaasa University. You can connect with him on LinkedIn.