Which Vitamin Deficiency Causes Hair Loss?

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Medically reviewed by Brendan Camp, MD

Many factors can contribute to hair loss, including genetics, childbirth, and certain diseases. Hair loss can result from a lack of nutrient-rich foods, restrictive eating, sudden weight loss, low-calorie intakes, and obesity—all of which can lead to nutritional deficiencies. Excessive intake of certain vitamins and minerals can also disrupt your hair growth cycle and contribute to hair loss.

Changing your diet and using supplements (or decreasing others) may help slow or even reverse hair loss. Research has found that plant-rich diets like the Mediterranean diet, which focuses on foods rich in antioxidants and anti-inflammatories, stimulate hair growth and can reduce hair loss.

If you struggle with hair loss, it may be helpful to consider your nutritional status and address areas where you may be lacking.

Vitamin and Mineral Deficiencies That Cause Hair Loss

The role that vitamin and mineral deficiencies play in hair loss is not yet well understood, but more and more evidence suggests that having certain deficiencies may lead to hair loss in some people.

Vitamin D

As a steroid hormone and fat-soluble vitamin, vitamin D plays a role in your body’s calcium absorption, bone mineralization, and immune system function. It may also play a role in hair health.

Vitamin D might affect your hair growth cycle. Vitamin D deficiency has also been linked to hair loss in people with rickets (bone softening and weakening due to extreme vitamin D deficiency) and people with alopecia areata, an autoimmune disease that attacks the hair follicles.

B Vitamins

Many people assume that a lack of biotin (B7) contributes to hair loss. However, biotin deficiency is rare and usually caused by an inherited condition. There’s little evidence that supplementation prevents or treats hair loss in people who are not biotin deficient.

Low B2 (riboflavin), B12, or folate has also been linked to hair loss, but little research indicates whether supplementation can promote hair regrowth.

Iron

Some research shows that iron plays a role in hair growth by regulating various genes in your hair follicles. Iron deficiency and anemia can cause telogen effluvium (rapid hair loss). It’s common in people assigned female at birth who experience hair loss.

Anemia is low red blood cells or hemoglobin, a protein in red blood cells that carries oxygen. The most common cause is low iron. Menstruating (especially heavy periods) can also increase your risk.

Additional research is needed to develop iron supplementation guidelines for people experiencing hair loss due to iron deficiency.

Vitamin C

Also known as ascorbic acid, vitamin C plays several important roles in the body. For example, it helps your body absorb iron. For this reason, people with hair loss due to an iron deficiency will likely need to supplement with vitamin C—or ensure they get plenty in their diet.

Scurvy is the medical term for Vitamin C deficiency. It has been linked to anomalies in body hair including:

• Corkscrew hairs: Twisted or coiled hairs
• Follicular hyperkeratosis: Follicles (tiny openings on the skin through which hairs grow) contain excessive keratin, the protein that helps form hair
• Swan neck hairs: Hairs that bend in multiple places

However, there’s still no clear evidence linking vitamin C with hair loss.

Zinc

Zinc deficiency can cause telogen effluvium as well as thin, white, brittle hair and other skin-related issues. One study of over 300 people with hair loss showed low zinc levels. However, research on zinc supplementation to treat hair loss is limited.

Taking too much zinc over an extended period can also lead to side effects like lowered immunity, reduced HDL (good) cholesterol levels, decreased ability to absorb magnesium, and a copper deficiency.

Vitamins and Hair Health

Hair follicles go through four cycles or phases:

• Anagen phase: Growth phase
• Catagen phase: Transitional phase
• Telogen phase: Resting phase
• Exogenous phase: Release of hair

The anagen phase can last anywhere from 2-7 years. During this phase, 90% of your 100,000 hair follicles should be in the process of growing. This growth requires essential nutrients like proteins, vitamins, and minerals to produce healthy hair efficiently. Factors like a poor diet, sudden weight loss, or restrictive eating can shorten the anagen phase and lead to quicker hair loss.

When you get plenty of essential vitamins and minerals, these nutrients can:

• Reduce inflammation
• Decrease oxidative stress
• Improve immunity
• Improve altered genetic expression (genetic causes of hair loss)

These factors can help prevent hair loss and restore hair growth. However, more research is needed to fully understand the roles and benefits of specific nutrients in hair loss management.

Can Too Many Vitamins Cause Hair Loss?

Taking excessive amounts of vitamins and minerals—including vitamin A, vitamin E, and selenium—can also result in hair loss.

Vitamin A

While adequate intakes of vitamin A are needed for healthy skin and hair, having too much in your system from retinoid skin treatments or excessive supplementation can cause unintended consequences like hair loss.

Once your body’s needs for vitamin A are met, supplementation can become toxic and disrupt hair growth.

Vitamin E

Little research exists on the role of vitamin E in hair growth, but some small studies show supplementation may help reduce hair loss.

That said, excess supplementation can cause hypervitaminosis E (vitamin E toxicity) and can lead to hair loss, as well as an increased risk of bleeding and thyroid issues. One study found that people taking 600 International Units (IU) per day for 28 days—30 times the daily recommended intake—experienced hair loss.

Selenium

There is a lack of research on whether selenium can prevent hair loss, yet many hair regrowth products contain this trace element. Researchers in one review note that this is surprising given the fact that selenium’s toxicity is well documented and can often lead to hair loss—as well as skin lesions, gastrointestinal issues, and memory challenges—if you take too much.

How To Find Out if You Are Deficient

Always consult a healthcare provider before trying a supplement, especially since supplementing with certain vitamins like D, A, K, and E can build up in your system and reach toxic levels. A provider can address underlying factors that may be contributing to your nutritional deficiencies. They can also run tests to determine your nutritional status.

Blood, saliva, and urine tests can detect certain nutritional deficiencies. Even your omega-3 status can be measured with a simple blood draw. These measurements can be affected by factors like infections, underlying medical conditions, and even stress. Therefore, your provider may need to consider these factors before recommending supplementation.

Treatment Tips

Other strategies can potentially help reduce hair loss and promote regrowth. Here are some things to consider if you experience thinning hair or more than normal hair loss.

Lifestyle Changes

Experiencing hair loss might motivate you to wear your hair differently to cover up thinner areas or buy products that claim to promote hair growth. However, most dermatologists recommend simple self-care tips to help protect your hair from further damage.

For instance, the American Academy of Dermatology Association (AAD) recommends the following:

• Gently wash and condition your hair, keeping in mind that hair that is thinning or falling out is fragile and easily damaged
• Choose a gentle shampoo and condition after every wash
• Wrap your hair in a microfiber towel after showering to reduce the time spent blow-drying your hair
• Limit the use of flat irons, curling irons, and other heated tools as these can be hard on your hair
• Eat a nutrient-rich diet
• Focus on managing your stress
• Ensure you are getting plenty of sleep

Supplements

Most people turn to supplements for hair loss. However, the AAD recommends avoiding supplementation until after evaluation by a medical professional. Each person is unique and what works for one person may not work for another. Hair loss is a complex issue with many potential contributing factors.

In addition, getting too much of certain vitamins and minerals might exacerbate the issue. There is no best vitamin or mineral for hair loss. Addressing hair loss with supplements requires knowing your body’s unique needs and choosing what will meet those needs.

Finally, there has been great interest in using biotin to address hair loss, but research on its benefits is limited. While a few small studies have shown that it can improve hair and nail health, the connection is unclear. Some supplements contain as much as 2,500-5,000 micrograms (mcg) of biotin. This is an extremely high dose considering the recommended amount for adults is only 30 mcg a day.

High levels of biotin in your blood can also affect some lab tests, including tests used to diagnose a heart attack. Always consult a healthcare provider before trying biotin for hair loss.

Medications and Other At-Home Treatments

Dermatologists typically treat hair loss. Dermatologists are medical doctors who specialize in skin, hair, and nail conditions. They may recommend the over-the-counter (OTC) medication Rogaine (minoxidil). This medication is applied to the scalp and can promote hair regrowth and prevent further hair loss. It can take about 6-12 months before you see results.

Other treatment options include the following:

• Laser caps and combs: These devices use low-level laser therapy (LLLT) to stimulate cell activity. While research is limited, one small study of 200 people found that using the laser devices three times a week for 26 weeks resulted in thicker and fuller hair overall.
• Microneedling: This minimally invasive procedure involves using tiny needles to make shallow, repetitive punctures into the skin. It supposedly stimulates the healing process, causing the body to produce more collagen and elastin.
• Platelet-rich plasma injections (PRP): This therapy involves injecting plasma from your blood into your scalp. Early research indicates it may be useful for treating hair loss, but more evidence is needed before it’s broadly recommended.

One study found that people with hereditary hair loss who used minoxidil twice a day alongside weekly microneedling experienced more hair regrowth than those using minoxidil only. Always consult a dermatologist before trying a device because they can worsen some scalp conditions.

When To See a Healthcare Provider for Hair Loss

See a board-certified dermatologist or a primary care physician if you notice sudden or patchy hair loss or more than usual hair loss when you’re combing or washing your hair. Hair loss can signal an underlying medical issue like a thyroid condition, stress, skin condition, scalp infection, menopause, and more.

The earlier the cause of your hair loss is identified, the sooner you can begin treatment and the better your prognosis for hair regrowth. Depending on the underlying cause, many people who experience hair loss experience hair regrowth with the right treatment and interventions.

A Quick Review

Hair loss is a common problem that affects nearly 80 million people in the United States. While many factors can lead to hair loss, it’s sometimes related to nutritional deficiencies caused by low body weight, restrictive eating, eating disorders, obesity, and other conditions. Even taking too much of a particular vitamin or mineral can lead to hair loss.

Reach out to a dermatologist or your primary healthcare provider if you suspect that your hair loss is related to a lack of certain vitamins or minerals. They can make treatment recommendations based on the underlying cause.

Read the original article on Health.com.