Adah was born in Palakkad districtKerala. Her father was a captain in the merchant navy and mother is a dancer. Adah did her schooling from Auxilium Convent in Pali hill where she also lives. She later graduated from Mumbai University with a degree in psychology. She is a gymnast and is currently completing her graduation in Kathak from Gopi Krishna’s Dance Academy.
Sharma's acting in the film 1920 earned her enthusiastic reviews from Bollywood film critic Taran Adarsh praising her performance saying "Adah gets the meatier part and she takes to it like a fish takes to water. She's excellent!" while Times of India's Nikhat Kazmi commented "Adah Sharma delivers a consummate, skillful performance. She rolls up her eyes, speaks like a man, flings people around, eats raw flesh, crawls up pillars and generally keeps you glued to your seats.