Horsetail for Hair Loss: Evidence, Safety, and How to Use It

Seeing more strands in the drain or extra scalp peek-through can be unsettling. While genetics and hormones matter, nutrition, oxidative stress, and scalp environment play big roles too. Here’s what the research suggests about horsetail and its silica content for shedding and fullness—plus practical guidance and safety notes.

Hair loss 101: what’s modifiable

Common contributors include iron or zinc shortfalls, inadequate protein, oxidative stress, inflammatory scalp conditions, and harsh chemical or heat exposure. Reviews emphasize that oxidative stress—UV, pollution, chemicals, oxidized scalp lipids—accelerates hair fiber aging and fragility. Int J Cosmet Sci 2015; Europe PMC.

What the evidence says about horsetail & hair

• Silica improves tensile properties: In a 9-month RCT, daily stabilized silica (ch-OSA) improved hair tensile strength and morphology in women with fine hair. Although this trial used ch-OSA rather than a whole-herb extract, it supports silica’s role in stronger hair. Arch Dermatol Res 2007.
• Silicon & hair condition: Dermatology reviews point to associations between higher hair silicon content and lower hair loss rates/increased brightness, noting bioavailability differences across supplement forms. An. Bras. Dermatol. 2016 (PMC).
• Antioxidant potential of horsetail: Equisetum arvense extracts demonstrate antioxidative activity in vitro, relevant to counteracting oxidative stress implicated in hair damage. J Med Food 2010.

Bottom line: Evidence supports silica’s contribution to stronger, less breakage-prone hair; horsetail provides silica and antioxidants, making it a plausible adjunct—especially when paired with core nutrition and scalp care.

How to build a smart horsetail strategy

1. Start with fundamentals: Ensure adequate protein; check iron/ferritin and zinc with your clinician if shedding is persistent.
2. Choose quality & form: Use standardized horsetail or a bioavailable silica (e.g., ch-OSA), with third-party testing for contaminants.
3. Be consistent: Track for 12 weeks before judging results. Expect reduced breakage first, then a gradual look of fullness.
4. Layer antioxidant care: Scalp-friendly routines (UV protection, gentle cleansing, avoiding over-processing) help maintain gains. See oxidative stress background: review.

Safety: thiaminase, heavy metals & who should avoid it

• Thiaminase concern (vitamin B1): Some horsetail species can contain thiaminase, which degrades thiamine; choose reputable products and consult a clinician if pregnant, nursing, dealing with kidney issues, or on diuretics. Safety summaries: CIR 2021; regulatory review: EMA.
• Heavy-metal testing: Equisetum species can accumulate metals from soil; favor brands with transparent contaminant testing. See USGS survey of Equisetum metal uptake: USGS Bulletin.

Quick FAQ

How long until I notice changes?

Plan on 8–12 weeks for noticeable differences in breakage and texture; 3–6 months for fuller “feel.” Data from silica trials suggest gradual improvements over months. Wickett et al., 2007.

Is topical horsetail enough?

Topicals can support scalp comfort and cosmetic feel, but oral intake of bioavailable silica has the stronger evidence for tensile properties. Combining approaches plus lifestyle changes yields the best outcomes.

Sources

1. Wickett RR, et al. Effect of oral choline-stabilized orthosilicic acid on hair tensile strength & morphology. Arch Dermatol Res. 2007. Springer / Europe PMC.
2. de Morais EC, et al. Use of silicon for skin & hair care: chemical forms and efficacy. An. Bras. Dermatol. 2016. PMC PDF.
3. Cetojević-Simin DD, et al. Antioxidative/antiproliferative activities of Equisetum arvense extracts. J Med Food. 2010. Europe PMC.
4. Trüeb RM. Oxidative stress and hair. Int J Cosmet Sci. 2015. Wiley PDF; Europe PMC abstract.
5. Cosmetic Ingredient Review (CIR). Safety assessment of Equisetum arvense-derived ingredients (cosmetic use). 2021. PDF.
6. European Medicines Agency (EMA). Assessment report on Equisetum arvense L., herba. 2016. PDF.
7. USGS. Metal absorption by Equisetum (horsetail). Bulletin 1278-A.