Smith attended the University of Alabama from 1997 through 2000 and played at defensive tackle for the Crimson Tide (UA college football team). He made a total of 177 tackles, 60 quarterback pressures, 10.5 sacks and blocked three kicks in his playing time. From 1998 - 2000 he was a All-Southeastern Conference second-team choice
In 2001 the New Orleans Saints drafted Smith in the third round of the 2001 NFL Draft. In his rookie season with the Saints he played in only six games as a backup defensive lineman and made a total of eight tackles. In 2002 he appeared in nine games and 19 total tackles and 3.5 sacks. The following season, 2003, Smith played in 15 games, with nine starts, and made 42 total tackles and one sack. He was injured before the start of the 2005 season and ended up not appearing in a single game in 2005. In 2006, the Oakland Raiders signed Smith to a contract but he once again was injured and was forced to sit out the 2006 season on the Raiders injury reserve list. On June 8, 2007 the New England Patriots signed Smith to a one year 510,000 thousand dollar contract. The Patriots released Smith before the beginning of their 2007 regular season on August 22, 2007.