🌿 A beauty tip shared on TikTok and Instagram scientifically validated

Social media is full of beauty advice praising the virtues of rosemary for the skin, but this time, science is getting involved with promising results. A team from the University of Pennsylvania discovered that this aromatic plant could revolutionize skin healing by preventing undesirable marks.

The researchers looked into rosemary after observing its skyrocketing success on TikTok and Instagram. Jiayi Pang, an undergraduate student, and Emmanuel Rapp Reyes, a PhD student, decided to scientifically study these popular claims under the supervision of Professor Thomas Leung. Their curiosity was rewarded when they identified carnosic acid, an antioxidant present in rosemary, as the main actor in this healing phenomenon.


Experiments conducted on mice revealed that carnosic acid accelerates wound closure while restoring hair follicles, sebaceous glands, and even cartilage. The mechanism involves the activation of the TRPA1 receptor, a nerve sensor in the skin essential for tissue regeneration. When this receptor is absent, the beneficial effect of rosemary completely disappears, confirming its central role in the process.

The team found that other herbs like thyme and oregano can also activate TRPA1, but rosemary stands out for its potency and safety. Unlike mustard oil or imiquimod which irritate the skin, rosemary offers a gentle alternative. The effect remains localized: application must be done directly on the wound to be effective.

However, scientists recommend caution and advise consulting a doctor before using rosemary-based products. This accessible and affordable plant opens up interesting prospects for patients prone to hypertrophic scars.

The TRPA1 receptor: a skin regeneration switch

The TRPA1 receptor is a protein located on the surface of nerve cells in the skin that reacts to chemical and thermal stimuli. Its activation triggers a cascade of biological signals promoting tissue repair.

This receptor belongs to the family of ion channels and activates in the presence of certain compounds, like those in rosemary. When stimulated, it allows calcium ions to enter the cells, which activates the genes responsible for regeneration.

Regarding healing, TRPA1 helps maintain the balance between fibrous tissue formation and complete skin regeneration. Its role is particularly important for reconstituting structures like hair follicles.

Previous studies had already shown that the absence of this receptor systematically leads to scar formation, even for minor injuries.