As a teacher earning a doctorate, Mr. Bennett moved the family often. Jana and her four sisters spent time in Kansas, Minnesota and New Hampshire before the family moved to England and settled in East Sussex, when Jana was 13.
She went to St. Anne’s College, Oxford University, and graduated in 1977 with a degree in philosophy, politics and economics. (An amateur singer, she was recruited to join a band by another Oxford student and a future prime minister, Tony Blair.) She earned her master’s degree in international relations from the London School of Economics in 1978. The following year, she joined the BBC as a news trainee.
Her early journalistic work included news documentaries, including “The Disappeared: Voices from a Secret War,” about the repressive military regime in Argentina in the late 1970s and 1980s. She and John Simpson, a fellow BBC journalist, also wrote a book, “The Disappeared and the Mothers of the Plaza” (1986), which included firsthand accounts by mothers to find the thousands of children whom the Argentine regime had “disappeared.”
While working on the BBC’s Newsnight program, Ms. Bennett met Mr. Clemmow, an editor and executive at the BBC. They married in 1995.
In addition to her husband, she is survived by a daughter, Alexandra Bennett-Clemmow; a son, Skomer Bennett-Clemmow; and her sisters Robin King and Kimberly, Candace and Shelley Bennett.
In 1999, she left the BBC and became head of TLC for Discovery in Washington, D.C. There, she introduced reality dramas and interior design programs, some of them based on popular British formats, which boosted not only ratings but revenues.
She returned to the BBC in 2002 when she was named director of television.
After her diagnosis in May 2019, Ms. Bennett initially told few people of her illness because she wanted to avoid “an extended wake,” her longtime friend and BBC colleague, Lorraine Heggessey, wrote Tuesday in The Guardian.
She threw herself into her work on the boards of the British Library and the Headlong Theater Company. She went public about her illness in December 2019, when she joined a nonprofit group, OurBrainBank, an app that allows people with glioblastoma to consult doctors around the world and promotes research into the disease.