Horsetail

Horsetail is the richest plant source of bioavailable silicon — contains 5-8% silicon as orthosilicic acid. Used for hair, skin, nails, and bone density. A 2016 study found horsetail extract improved hair tensile strength and thickness over 90 days. Also contains thiaminase (destroys vitamin B1) — long-term use without B1 supplementation can cause thiamine deficiency. Tea form is safest (hot water inactivates some thiaminase). Dose: 300-900mg/day extract. --- *Reviewed by the Dose AI Research Team and Clinical Advisory Board* *Last updated: 2026-04-06*