Hair loss supplements target different mechanisms of hair thinning. Understanding whether your hair loss is driven by DHT (male/female pattern), nutritional deficiency, or stress determines which ingredients to look for.
- Saw palmetto: 320 mg/day of liposterolic extract reduced hair loss and improved hair density in a 2012 Journal of Alternative and Complementary Medicine RCT. Works as a 5-alpha reductase inhibitor (blocks DHT conversion) — the same mechanism as finasteride, but milder.
- Biotin (B7): Effective only when you are deficient (which is rare in well-nourished adults). At 2,500–5,000 mcg/day, biotin improves hair quality in deficient individuals. Supplementation above 10,000 mcg may interfere with thyroid lab tests.
- Marine collagen peptides: 500 mg/day of marine-derived collagen improved hair thickness by 31% after 6 months in a 2015 Journal of Cosmetic Dermatology study. Provides amino acids specific to keratin synthesis.
- Iron (ferrous bisglycinate): Critical for women with hair loss — ferritin levels below 40 ng/mL are associated with telogen effluvium. 18–27 mg/day of chelated iron corrects deficiency-related shedding within 3–6 months.
- Zinc: 15–30 mg/day supports hair follicle health. Deficiency causes telogen effluvium. Zinc picolinate is the best-absorbed form.
- Pumpkin seed oil: 400 mg/day increased hair count by 40% over 24 weeks in a 2014 Evidence-Based Complementary and Alternative Medicine RCT. Mild 5-alpha reductase inhibition without hormonal side effects.
For androgenetic alopecia (pattern baldness): saw palmetto + pumpkin seed oil + zinc. For telogen effluvium (stress/deficiency shedding): iron + biotin + marine collagen. For thinning hair without clear cause: a comprehensive formula covering both pathways.
Hair grows approximately 0.5 inches per month. Any supplement addressing hair follicle health requires 3–6 months of consistent use before visible improvements. Claims of "results in 2 weeks" are not supported by the biology of hair growth cycles.