An old faithful! Tea tree oil is an essential oil sourced from the leaves of the Australian Melaleuca tree. It can usually be found as part of a skincare formula for blemish-prone skin. Tea tree oil helps to nix acne-causing bacteria and fungus. A word of warning: tea tree oil should always be diluted and never used alone.
Fact checked by Hannah English, B Pharm Sci (Hons), Skincare Expert & Digital Creator