Marya Justine Hornbacher is an American author and freelance journalist, born on April 4, 1974. She gained widespread recognition with her book Wasted: A Memoir of Anorexia and Bulimia, an autobiographical account of her struggle with eating disorders, written when she was only twenty-three. The book has been translated into sixteen languages and sold over a million copies in the U.S.

Her second book, the acclaimed novel The Center of Winter, published in 2005, has been praised as "masterful," "gorgeous writing," and "a stunning achievement of storytelling." The novel is told in three voices: by six-year-old Kate, her mentally ill brother Esau, and their mother.