What nutrient deficiencies are known to cause hair loss?

Reviewed by Yoshinori Abe, MD

Internal Medicine

Hair loss is often linked to nutritional deficiencies, particularly low levels of iron, zinc, vitamin D, and B vitamins (such as biotin and B12). These nutrients play a critical role in hair follicle health, growth cycles, and scalp function. When your diet lacks them, hair may become thin, brittle, or shed more than usual.

Because hair loss can also signal thyroid issues, hormonal imbalances, or other underlying conditions, identifying the root cause is key. Take a free, instant, online symptom check to better understand what may be driving your hair loss and get clear guidance on your next steps—no appointment or sign-up required.

Reviewed for medical accuracy: 07/15/2026

Quick answers

Frequently Asked Questions

4 answers

The most common questions people search after this page

Concerned about your symptoms?

Start a symptom check

Explanation

Hair loss can happen if you don't get enough of certain nutrients in your diet.

Key Nutrients Associated with Hair Loss:

Iron: Iron is very important for healthy hair. When you don't get enough iron, it can make your hair fall out. This is because iron helps your blood carry oxygen to your hair roots, which is needed for hair to grow.
Zinc: Zinc helps your hair grow and stay healthy. Without enough zinc, your hair might become weak and fall out.
Vitamin D: Vitamin D is also important for hair health. Not having enough vitamin D can make your hair thin or fall out.
B Vitamins: B vitamins, like B12 and biotin, help your hair grow. If you don't get enough of these, you might notice more hair falling out.

Eating a balanced diet with these nutrients can help keep your hair strong and healthy. If you're experiencing hair loss and want to understand what might be causing it, try our free AI symptom checker or talk to a healthcare provider.

(References)

Trost LB, Bergfeld WF, & Calogeras E. (2006). The diagnosis and treatment of iron deficiency and its .... Journal of the American Academy of Dermatology, 16635664.
Rushton DH. (2002). Nutritional factors and hair loss. Clinical and experimental dermatology, 12190640.
Almohanna HM, Ahmed AA, Tsatalis JP, & Tosti A. (2019). The Role of Vitamins and Minerals in Hair Loss: A Review. Dermatology and therapy, 30547302.

Tell your friends about us.

We would love to help them too.

For First Time Users

What is Ubie’s Doctor’s Note?

We provide a database of explanations from real doctors on a range of medical topics. Get started by exploring our library of questions and topics you want to learn more about.

Was this page helpful?

Purpose and positioning of servicesUbie Doctor's Note is a service for informational purposes. The provision of information by physicians, medical professionals, etc. is not a medical treatment. If medical treatment is required, please consult your doctor or medical institution. We strive to provide reliable and accurate information, but we do not guarantee the completeness of the content. If you find any errors in the information, please contact us.