Diego Klattenhoff started acting professionally in 2001, debuting in 2 episodes of Doc. He went on to make one-time appearances in Mutant X, Veritas: The Quest, 1-800-Missing, Smallville, and Stargate SG-1. His first recurring role was as Jacob in the Canadian show At the Hotel. In 2004, he had his first movie role as Shane Oman in Mean Girls. Later, the actor had performances in the films Cube Zero, Ice Princess, Lucky Number Slevin, and The Informers.
At the same time, he starred in the TV movies Shania: A Life in Eight Albums and Fire Serpent, among others. Also during this period, he played Derek in the TV series Whistler and Ivan Palacinke in the ABC series Men in Trees. From 2009 to 2010, he starred as Mike Callahan in the NBC show Mercy. He became further known for playing Mike Faber in the Showtime series Homeland. Following this, he joined the main cast of The Blacklist as Donald Ressler, a role he’s been playing since 2013. Simultaneously, he starred in the films Kilimanjaro, After Earth, Pacific Rim, Lavender, and most recently, Radius.
Apart from his workout routine, the actor stays on top shape by watching what he eats. Of course, part of his fitness regimen is that he also consumes the right foods. After all, proper nutrition is also crucial for him to maintain his figure and even increase his strength. The Diego Klattenhoff diet plan involves him loading his body with carbs in the morning and filling up on protein after his workouts. Not only does he watch what he eats, but he also minds what he drinks. “Lay off the suds,” said the actor. “If you do drink beer—stay light. I usually skip them altogether and go with the vodka sodas or whiskey waters.”