Rosemary extract has been a viral trend in skincare routines on social media platforms like TikTok and Instagram, and now, scientific research from the Perelman School of Medicine at the University of Pennsylvania is backing up the hype. A recent study published in JCI Insight revealed that a compound found in rosemary leaves has the potential to significantly improve the healing of skin wounds and reduce scarring.
Senior author, Thomas Leung, MD, Ph.D., an associate professor of Dermatology at Penn, explained the significance of the findings, stating that many skin injuries can result in scars, leading to long-term cosmetic and functional issues. The research suggests that rosemary extract, particularly the antioxidant carnosic acid, can shift the healing process from scarring to healthy skin regeneration, a feat that has not been consistently achieved in humans before.
The study was led by Penn undergraduate student Jiayi Pang and Ph.D. candidate Emmanuel Rapp Reyes, who were inspired by the widespread use of homemade rosemary extract serums and products containing rosemary in the beauty community. They decided to investigate the healing properties of rosemary in the lab to uncover its potential benefits.
Using a cream containing carnosic acid, an antioxidant primarily found in rosemary, the researchers conducted experiments on mice to accelerate wound closure and restore various skin structures. They discovered that a specific nerve sensor in the skin, TRPA1, known for its role in scarless healing, played a crucial role in the healing process induced by the carnosic acid cream.
Interestingly, when the cream was tested on mice lacking the TRPA1 sensor, its healing effects were diminished, emphasizing the importance of this particular sensor in the process. While other herbs like thyme and oregano were also found to activate TRPA1, rosemary stood out for its potency and safety compared to other natural ingredients that can cause irritation and inflammation.
The researchers observed that the scarless healing effect of rosemary was localized to the site of the injury, highlighting the importance of targeted application. They recommend consulting healthcare professionals before incorporating rosemary skincare products into daily routines or creating homemade concoctions.
Despite the need for further research on human subjects, the accessibility and cost-effectiveness of rosemary make it a promising candidate for wound care, particularly for individuals prone to excessive scarring. Thomas Leung expressed pride in the young scientists who led the research, emphasizing the importance of seeking answers to everyday questions through scientific inquiry.
In conclusion, the study sheds light on the potential of rosemary extract, specifically carnosic acid, in promoting healthy skin regeneration and reducing scarring. The findings open up new avenues for exploring the use of rosemary in skincare and wound healing, offering hope for improved outcomes in skin injuries.

