Why hair-care formulations reach for rosemary
Two compounds explain rosemary's persistent place in scalp formulations: 1,8-cineole and carnosic acid. The first is a mild vasodilator (the warm tingling sensation is real and harmless at cosmetic concentrations); the second is an antioxidant that survives oil infusion. Independent randomised trials on rosemary oil and androgenetic alopecia have produced mixed but cautiously positive results - we sell rosemary products as traditional hair-care, not as a treatment.
Cosmetic versus aromatherapy concentrations
Undiluted rosemary essential oil should never be applied directly to skin. Our hair oils, balms and shampoos use rosemary at cosmetic concentrations (typically below 1% essential oil, often as warm infusion in a carrier oil base). That ratio gives the scent and the mild scalp stimulation without the irritation, sensitisation or pregnancy cautions associated with neat essential oil.