Hair Loss and Vitamin D: Clues, Tests, and Next Steps

Vitamin D deficiency is one possible contributor to increased shedding, but the way your hair looks cannot confirm that vitamin D is the cause. Diffuse thinning or more hair in your brush may also follow illness, stress, childbirth, or a change in medication, while a widening part can point toward pattern hair loss.

If you suspect a deficiency, ask a health care professional whether a 25-hydroxy vitamin D blood test makes sense for you, especially if you have risk factors such as limited sun exposure or a condition that affects nutrient absorption. Share when the shedding began, any other symptoms, your medications and supplements, and any recent major health changes so they can interpret the result in context.

A low vitamin D result does not prove it is the only reason you are losing hair; depending on your symptoms and history, your clinician may consider other causes, including iron deficiency or thyroid problems. Our guide to hair loss and nutrient deficiency can help you organize questions about nutrition, and our team also offers Understanding Hair Loss from the Inside Out, a digital eBook on hair loss and nutrient deficiency.

Check the product’s listed specifications when evaluating look beyond vitamin d.

If testing shows a deficiency, work with your clinician on an appropriate vitamin D plan rather than taking high doses on your own, since too much vitamin D can be harmful. If the shedding is sudden or severe, you have bald patches, or your scalp is painful or inflamed, seek an evaluation instead of assuming a supplement will address it.