Allium Cepa Bulb Extract
You probably meet this guy more often in your kitchen than in the bathroom, but yes, onion extract is also used as a skincare ingredient. Its major skin benefit seems to be that it can improve the cosmetic appearance of postsurgical scars (there is also a scar-fading gel called Mederma, that has hardly anything else in it but onion extract).
We also saw some manufacturer claims that onion is not only a scar healer, but it has also antibacterial and antifungal activity, it can help to reduce acne and stimulate hair growth.
Show me some proof
- Journal of Cosmetic Dermatology, Draelos, Zoe Diana, Volume 7 (2) - Jun 1, 2008, The ability of onion extract gel to improve the cosmetic appearance of postsurgical scars
- Draelos, Zoe D., Leslie Baumann, and Alan B. Fleischer. "A new proprietary onion extract gel improves the appearance of new scars: a randomized, controlled, blinded-investigator study." The Journal of clinical and aesthetic dermatology 5.6 (2012): 18.