Nakahara was born in Honolulu. Before becoming an actress, Nakahara moved to San Francisco to pursue a career in art. In 1967, she married David Wallett and moved to Los Angeles where she began a career as an actress. Halfway through the first season of M*A*S*H, she landed the part of Nurse Kellye in which she appeared in more than 150 episodes of the long-running series. Following the series finale of M*A*S*H, Nakahara appeared in television commercials as a spokesperson for IBM. Additionally, she appeared in several other television shows, had a small part in the films Clue (1985) as Mrs. Ho, the domestic cook, and in 1995’s Black Day Blue Night. She also played a labor and delivery nurse in the 1988 John Hughes film She’s Having a Baby.

Nakahara died from cancer at her home in Pasadena, California, on February 16, 2020. She is survived by her husband, two children and four grandchildren.