A self-described troublemaker in her youth, she eventually became a model after being discovered by a talent scout while working in a bakery. She started as a model for the men's magazine Slitz, for which she has been featured multiple times hence. She has also appeared in many other magazines, including Imagine, Magazine Sweden, Sizzle Magazine, Babes Magazine and Most Wanted. She has also participated in the Baywatch summer tour and Summer 2000 Swedish Bikini Show, along with some Swedish television work. Additionally, she was a spokesmodel for TAKI casuals at the Sundance Film Festival.
While popular in Sweden, she has earned little exposure outside of Europe in spite of her wishes to become more internationally well-known.
In 2004, Janna's official website closed down and Swedish media websites reported Janna had quit the modelling scene and regretted posing nude. She currently resides in Sweden, helping her partner run his restaurant.