Multivitamins for Hair Loss: Evidence-Based Recommendation
A standard multivitamin is not recommended for treating hair loss in people without documented nutritional deficiencies, as there is insufficient evidence that supplementation helps when deficiency is absent, and some supplements may actually worsen hair loss or cause toxicity. 1
The Critical Distinction: Deficiency vs. Supplementation
The evidence consistently shows that correcting documented deficiencies is beneficial, but supplementing when levels are normal lacks supporting research. 1
When Testing and Supplementation May Be Warranted
You should first determine if specific nutritional deficiencies exist through targeted testing rather than empirically taking a multivitamin:
Vitamin D deficiency (defined as <20 ng/mL) shows the strongest association with hair loss, with 70% of alopecia areata patients being deficient versus 25% of controls, and lower levels correlate inversely with disease severity. 2
Zinc deficiency is associated with hair loss, with serum zinc levels tending to be lower in patients with alopecia areata, particularly those with resistant disease lasting >6 months. 2
Folate deficiency may contribute to hair loss given its role in nucleic acid production in rapidly dividing hair follicle cells. 3
Iron deficiency (measured by serum ferritin) is the most common nutritional deficiency worldwide and a sign of chronic diffuse telogen hair loss, though evidence specifically linking it to alopecia areata is conflicting. 3, 2
The Evidence Landscape
The current body of literature consists largely of small case-control studies and case reports that preclude definite conclusions about micronutrients' role in hair loss. 3 The American Journal of Clinical Dermatology's comprehensive 2017 review explicitly states that definitive clinical recommendations for routine supplementation require additional studies in larger populations with prospective design. 3
What the Research Actually Shows
Micronutrients play important but not entirely clear roles in normal hair follicle development and immune cell function. 4
Large double-blind placebo-controlled trials are still required to determine the effect of specific micronutrient supplementation on hair growth in those with both micronutrient deficiency and non-scarring alopecia. 4
While 60% of dermatologists in one survey recommended vitamins and minerals for at least one type of hair loss, this reflects practice patterns rather than evidence-based efficacy. 5
The Recommended Approach
For patients with no risk factors for nutritional deficiency, laboratory evaluation searching for nutritional deficiencies is not warranted, and supplementation is not recommended. 1
Risk Factors That Warrant Testing
Screen for these risk factors through medical and dietary history before considering testing:
- Restrictive diets (vegan, extreme calorie restriction)
- Malabsorption conditions (celiac disease, inflammatory bowel disease)
- Recent major physiologic stress (surgery, childbirth, severe illness)
- Medications that interfere with nutrient absorption
- Limited sun exposure (for vitamin D specifically) 3
If Deficiencies Are Documented
Vitamin D supplementation is recommended for patients with levels <20 ng/mL, though no double-blind trials have yet examined oral supplementation as a treatment strategy specifically for alopecia areata. 2
Zinc supplementation may contribute to hair health when deficient, particularly in patients with alopecia areata and telogen effluvium. 2
Correct any documented deficiency with targeted supplementation rather than a general multivitamin. 1
Critical Caveats
Some supplements carry the risk of worsening hair loss or causing toxicity. 1 For example:
- Excessive vitamin A can actually cause hair loss
- Indiscriminate supplementation without documented deficiency has no proven benefit and potential harm
Patients must be informed that research supporting supplementation in the absence of documented deficiency is lacking. 1 The tendency to spontaneous remission in many hair loss conditions (34-50% of alopecia areata patients recover within one year without treatment) makes it difficult to attribute improvement to supplementation. 2
Bottom Line
Rather than taking a multivitamin empirically, get tested for specific deficiencies if you have risk factors, and only supplement what is actually deficient. 1 If testing reveals normal levels, a multivitamin will not help your hair loss and may cause harm.