Carnosic acid [CA, (4aR,10aS)-5,6-dihydroxy-1,1-dimethyl-7- propan-2-yl-2,3,4,9,10,10a-hexahydrophenanthrene-4a-carboxylic acid] is a phenolic diterpene found in the leaves of the rosemary plant (Rosmarinus officinalis) and is used routinely as a food and cosmetic additive due to its antioxidant and antimicrobial properties. Carnosic acid as a food additive has a good safety profile and does not pose a health concern. Carnosic acid has demonstrated anti-inflammatory, anticancer, photoprotective, and antiadipogenic activities in vitro. Carnosic acid was shown to induce significant weight loss and reduced visceral adiposity in ob/ob mice fed a diet supplemented with carnosic acid. Carnosic acid is used as a preservative or antioxidant in food and nonfood products (e.g. toothpaste, mouthwash and chewing gum) -in which it has an antimicrobial effect on the microbes responsible for bad breath- or in skin care products.