Docus: AI-Powered Health Platform

Which Vitamin Deficiency Causes Hair Loss? Info and Tips

Apr 12, 2024 | 6 min read

Question on this topic? Get an instant answer from AI Doctor.Instant answer from AI Doctor.

Hair loss can often be attributed to deficiencies in specific vitamins and minerals, such as riboflavin, biotin, folate, vitamin B12, iron, and zinc. According to an NCBI publication, deficiencies in riboflavin, biotin, folate, and vitamin B12 have been specifically linked to hair loss. This article delves into these essential nutrients, explaining their roles and how insufficient levels can lead to hair loss. 

which vitamin deficiency causes hair loss

Understanding Hair Loss

The Hair Growth Cycle

Hair growth occurs in a dynamic cycle, consisting of three phases: 

  1. anagen (growth phase)
  2. catagen (transition phase)
  3. telogen (resting phase)

Each hair follicle independently cycles through these stages at different times. Typically, 90% of our hair is growing, while the rest is preparing to shed. Disruptions in this cycle can lead to noticeable hair loss, which might be a sign of underlying health issues, including nutritional deficiencies.

Common Causes of Hair Loss

Hair loss can stem from a variety of sources:

  • Genetics: Hereditary patterns of baldness or thinning hair, known as androgenetic alopecia, affect both men and women and are the most common cause of hair loss.
  • Environmental Factors: Pollution, exposure to certain chemicals, and even hard water can damage hair and disrupt growth cycles.
  • Nutritional Factors: A poor diet lacking essential vitamins and minerals can significantly impact hair health. For instance, deficiencies in iron, vitamin D, and biotin are known to cause hair loss.

To better understand how your symptoms align with possible vitamin deficiencies, consider using Symptom Checker, which offers insights but should not replace professional medical advice.

Docus AI Symptom Checker

Docus AI Symptom Checker

Just 3 simple steps to efficiently understand and manage your health symptoms online.

Role of Vitamins in Hair Health

Proper hair health hinges significantly on maintaining adequate levels of specific vitamins. Each vitamin plays a unique role in supporting hair growth and preventing hair loss. Below we outline the crucial vitamins, their benefits, sources, and the impact of their deficiencies.

Vitamin D

  • Importance: Vitamin D is critical for new hair follicle growth and helps prevent existing hair from entering the resting phase too quickly.
  • Deficiency Effects: Insufficient vitamin D can lead to hair loss, particularly conditions like telogen effluvium and alopecia areata.
  • Sources: Sun exposure for 10-15 minutes a few times a week, fatty fish, fortified dairy products, and egg yolks.
  • Supplementation: Recommended if you have limited sun exposure or dietary intake.

Vitamin B12

  • Role: Vital for DNA synthesis and red blood cell production, which are essential for healthy hair growth and scalp health.
  • Deficiency Signs: Hair loss, fatigue, and anemia, particularly in vegetarians or those with poor absorption.
  • Sources: Primarily animal products such as meats, dairy, and eggs.
  • Supplementation: Essential for vegetarians or people with absorption issues.

Riboflavin (Vitamin B2)

  • Function: Supports cellular function and energy production, contributing to healthy hair growth.
  • Deficiency Effects: Leads to brittle hair and hair loss.
  • Sources: Almonds, eggs, milk, and green vegetables.
  • Advice: A balanced diet generally provides sufficient riboflavin; supplements are rarely needed but can be useful in certain cases.

Vitamin E

  • Benefits: An antioxidant that enhances scalp circulation, reducing oxidative stress and improving hair health.
  • Sources: Nuts, seeds, spinach, and broccoli.
  • Supplementation: This can help if your diet lacks these nutrients.

Vitamin A

  • Importance: Essential for cell growth, including hair follicles. Helps regulate the hair growth cycle.
  • Risks: Both deficiency and excess can lead to hair loss.
  • Sources: Carrots, sweet potatoes, spinach, and kale.
  • Advice: It’s crucial to maintain a balanced intake as too much can be harmful.

Biotin (Vitamin B7)

  • Role: Well-known for promoting hair strength and thickness.
  • Deficiency Signs: Thinning hair, which is rare but can occur.
  • Sources: Eggs, nuts, whole grains, and meat.
  • Note: Be cautious with dosage when using supplements, as high levels can interfere with certain lab tests.

Niacin (Vitamin B3)

  • Function: Improves blood flow to the scalp, promoting hair health and texture.
  • Sources: Turkey, chicken, beef, and mushrooms.
  • Advice: Usually sufficient through diet, but supplements can assist in deficiency.

Folate (Vitamin B9)

  • Role: Essential for cell division and healthy hair growth.
  • Deficiency Effects: Hair loss, graying, and slowed growth.
  • Sources: Leafy greens, beans, legumes, and fortified grains.
  • Supplementation: Often recommended for pregnant women and those at risk of deficiency, always consult with a healthcare provider.

Other Factors Influencing Hair Health

Key Minerals Essential for Hair Health


Iron is crucial for producing hemoglobin, the protein in red blood cells that carries oxygen to tissues, including hair follicles. Proper iron levels support vibrant and healthy hair growth.

  • Signs of Deficiency: Include fatigue, paleness, and noticeable hair thinning.
  • Sources: Best obtained from red meat, spinach, lentils, and fortified cereals.
  • Supplementation: May be necessary, especially for women with heavy menstrual cycles or those following a vegetarian diet.


Zinc is vital for tissue growth and repair, playing a significant role in keeping hair follicle health.

  • Deficiency Impact: Can lead to hair loss, which is often reversible with proper zinc intake.
  • Sources: Include meat, shellfish, legumes, and seeds.


Selenium is crucial for the maintenance of healthy hair follicles and plays a role in preventing cellular damage from free radicals.

  • Deficiency Impact: While selenium deficiency is rare, it can lead to hair loss and weakened hair structure.
  • Sources: Brazil nuts, seafood, and grains are rich in selenium.
  • Caution: Excessive selenium intake can lead to toxicity, which may also cause hair loss, so moderation is key.

Lifestyle Factors Affecting Hair Health

  • Diet and Nutrition: Eating a balanced diet rich in vitamins and minerals is essential for hair health. Ensure you're getting enough protein, iron, and vitamin C, which are particularly important for hair growth.
  • Stress: Chronic stress can push hair follicles into a resting phase, skipping growth and leading directly to shedding.
  • Age: As we age, hair naturally begins to thin and lose its color; however, nutritional support can slow this process.
  • Hormonal Changes: Hormonal changes, such as those during pregnancy or menopause, can significantly affect hair growth and health.

Environmental Impact on Hair Health

  • Pollution: Environmental pollutants can damage hair by degrading hair proteins and causing scalp irritation, which impedes hair growth.
  • Hard Water: High mineral content in water can weaken your hair, making it more susceptible to breakage.

Hormonal Imbalances and Medical Conditions

  • Hormonal Changes: Conditions like pregnancy, menopause, and thyroid imbalances can dramatically affect hair health due to hormonal shifts.
  • Medical Conditions: Autoimmune diseases, such as alopecia areata, where the immune system attacks hair follicles, can cause hair loss. Scalp infections and diseases like lupus also significantly impact hair health.


If you want to read more about vitamin deficiency, we have articles:

Preventing and Treating Hair Loss Through Nutrition

Proper nutrition plays a pivotal role in maintaining healthy hair. Here's how you can use diet and supplements to enhance hair growth and prevent hair loss.

Diet Tips

  • Protein-Rich Foods: Hair is primarily made of protein, making adequate protein consumption crucial. Include chicken, turkey, fish, dairy products, and legumes in your diet.
  • Iron-Rich Foods: Foods like red meat, chicken, turkey, pork, spinach, and legumes help prevent iron deficiency, a major cause of hair loss.
  • Vitamins and Minerals: Consume a variety of fruits and vegetables. Citrus fruits for vitamin C, carrots and sweet potatoes for vitamin A, nuts and seeds for vitamin E, and seafood for zinc.


  • Iron and Zinc: Supplements can be helpful if you're deficient in these minerals. Always check with a healthcare provider before starting, as excessive intake can be harmful.
  • Vitamin D: Consider a supplement, especially during winter months or if you have limited exposure to sunlight.
  • Omega Fatty Acids: Omega-3 and Omega-6 supplements can enhance hair texture and prevent dry scalp.

Common Mistakes in Treating Hair Loss with Diet

  • Over-Supplementation: More is not always better. High doses of vitamins like A and E can actually cause hair loss.
  • Quick Fixes: While a healthy diet can support hair growth, it’s not a cure-all. Hair growth is a slow process, and changes in the diet will take time to show results.
  • Neglecting Other Factors: Diet alone might not be the reason for hair loss; consider genetic factors, stress levels, and health conditions.

When to See a Professional

  • Rapid or Unusual Hair Loss: If you’re experiencing sudden hair loss or shedding in large amounts, it’s important to seek professional advice.
  • Patchy Hair Loss: This can be a sign of alopecia areata, a treatable medical condition that requires specialist care.
  • Scalp Changes: Any changes in the scalp, such as scaling, persistent itching, or redness, suggest that you should consult a healthcare provider.

Frequently Asked Questions

Have more questions?Ask AI Doctor


Addressing vitamin deficiencies is essential for maintaining and restoring hair health. Here are key takeaways to consider:

  • Identify Key Nutrients: Vitamins such as D, B12, and A, and minerals like iron and zinc are essential for hair health. Deficiencies in these nutrients can lead to hair thinning and loss.
  • Be Proactive: Regularly assess your diet and lifestyle to ensure you're supporting your hair health adequately.
  • Seek Balance: Ensure a balanced intake of essential nutrients through a varied and balanced diet.
  • Monitor Hair Health: Keep an eye on your hair's condition and growth, and take action if you notice changes.
  • Consult Professionals: If dietary adjustments and over-the-counter solutions don’t seem to help, consult with a healthcare provider or a trichologist.
  • Explore Treatments: Consider advanced treatment options if conventional methods are insufficient.
AI Assistant

Have Questions?

Have a question on this topic? Submit it here and get an instant answer from our AI Doctor.

Please Note! This tool is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always consult a professional before taking any actions.

Make Informed Health Decisions

Talk to Docus AI Doctor, generate health reports, get them validated by Top Doctors from the US and Europe.

Make Informed Health Decisions

You’re only one click away from a life-changing journey

Virtual health assistant powered by AI
350+ world-renowned Doctors