Colleen Ann Fitzpatrick (born July 20, 1972) is an American pop music singer, songwriter, record producer, dancer, and actress better known by her stage name, Vitamin C. Her singles include "Graduation (Friends Forever)", "As Long As You're Loving Me", "The Itch", and her most successful hit the Top 20 Gold certified "Smile". Vitamin C is also the former lead singer of the alternative rock band Eve's Plum. As an actress, she has appeared in the films Hairspray, Get Over It, Da Hip Hop Witch, Scary Movie 2, and Dracula 2000.

She was ranked #76 on the Maxim Hot 100 Women of 2001. Mattel released a Vitamin C doll in 2000. She was a video game character in the game EA Sports Triple Play by EA Sports. Vitamin C has her own Tommy Hilfiger lipstick color developed after her signature yellow and orange hair.