John Ruiz, physician, son of Quintin Ruiz and María Ruiz Fernández, was born in Huatusco, Vera Cruz, Mexico, on September 25, 1903, into a family of thirteen children. He attended high school at St. Mary's in Kentucky and graduated from the University of Texas Pharmacy School in Galveston in 1925 and the University of Texas Medical Branch at Galveston in 1936. His internship was at Methodist Hospital in Houston in 1936–37. Ruiz practiced pharmacy in Houston at the Prescription House on Fannin Street and later at his own pharmacy on Canal Street from 1925 to 1932. From 1937 to 1974 he practiced medicine, at first on Navigation Street and later on Park Place Boulevard in southeast Houston. He was founder and president of the League of United Latin American Citizens in Houston and served on the board of directors of Ripley House (see SETTLEMENT HOUSES). He gave freely of his time to charity clinics and was known for encouraging, promoting, and often financing education of the underprivileged. His contributions to the community earned him Houston's Orchid Award. Ruiz's memberships included the American Medical Association and the Harris County Medical Society. He belonged to St. Christopher's Catholic Church, and Golfcrest County Club. He was married to Luz Stranahan in 1929, and they had three children. He resided in Houston all his professional life and died there on April 11, 1974, of an aortic aneurysm. He was buried at Garden of Gethsemani in Houston.