Also known as: Ricinus communis oil, JBCO (Jamaican black castor oil)
Popular folk remedy for hair thickening with no clinical trial evidence for regrowth.
Castor oil is rich in ricinoleic acid (~90%), which has anti-inflammatory properties and may enhance prostaglandin E2 activity in the scalp. The oil's humectant properties may improve hair shaft appearance and reduce breakage, giving an impression of thicker hair without affecting follicular biology.
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