Tom Arnold has lost 89 lbs. since his wife gave birth to their first child last year.
The 54-year-old comedian and his wife Ashley Groussman, 37, welcomed a baby boy, Jax Copeland Arnold, in Los Angeles in April after years of infertility struggles, and his son inspired him to start working out and watching his diet.
The 'Sons of Anarchy' star, who previously weighted 287 lbs. after struggling with depression and overeating, told People magazine: "Something inside of me changed. I knew I needed to live as long as I could."
He added: "The moment I saw [Jax] I realised he deserves the best."
Tom admitted that he used to be embarrassed by his body.
He said: "There was a lot of shame. One time I had a tailor come over and sew the weights into my suits - this is what you wear when you are 210, 220, 240, 300. That saved me the time of going into my closet and getting so upset and frustrated."
The actor is thrilled with the results after eliminating bread and cake from his diet, and hitting the gym for circuit-training and regular cardio sessions.
He said: "I have tons more energy to play with my son."
Tom, who was married three times, including to Roseanne Barr, before tying the knot with Ashley, 37, in 2009, previously credited his "miracle" baby for instantly improving their relationship.
He said: "When I held him, I accepted he was real and though he is obviously too good for me, he will never doubt that his father loves him very much. I also felt a kind of super love for Ashley. An intimacy and partnership and accomplishment I did not know possible."