Nyad has written four books: Other Shores (1978) about her life and distance swimming, Basic Training for Women (1981) describing a physical fitness program for women, Boss of Me: The Keyshawn Johnson Story (1999) about NFL wide receiver Keyshawn Johnson, and Find a Way (2015) about her quest to swim across the Florida Straits. She has also written for The New York Times, Newsweek, and other publications. Nyad and former professional racquetball player Bonnie Stoll formed a company called BravaBody which is aimed at providing online exercise advice to women over 40.

Nyad succeeded Rudy Maxa as host of the public radio program The Savvy Traveler, produced by Minnesota Public Radio, in July 2001 and remained host until the show ended in 2004.

Nyad was the subject of a short documentary "Diana" by the digital channel WIGS in 2012. As of 2006, she was a (long-time) weekly contributor to the National Public Radio afternoon news show All Things Considered (appearing on Thursdays), as well as the "business of sport" commentator for the American Public Media public radio program Marketplace business news. She was also a regular contributor to the CBS News television show Sunday Morning.

An analysis of Nyad's ability to dissociate during her marathon swims was covered by James W. Pipkin.

The documentary film The Other Shore was released in early 2013, some months before Nyad's swim from Cuba to Florida. In her 1978 autobiography, Nyad described marathon swimming as a battle for survival against a brutal foe—the sea—and the only victory possible is to "touch the other shore".