Actor Johnny Galecki is celebrating after finally kicking his smoking habit after 25 years.

The Big Bang Theory star has been a nicotine lover since he was a teenager, but he ended his addiction cold turkey earlier this month (Sep14).

He tells U.S. late night host David Letterman, "I smoked for about 25 years and with utter reckless abandon; I didn't keep track of how much. It was terrible..."

And he's already noticing the health benefits of being nicotine free.

He adds, "I feel great. I'm running twice as much as I used to, my taste buds are returning, I had an orange Tic Tac at work the other day (and) it was nearly orgasmic. I was like, 'Oh my God, that's the best! What is that, a $100 gourmet Tic Tac? That's incredible'.

"It was never a social thing for me, it kind of served my anti-social tendencies. Now I have to sit through dinners for the entirety of them without the excuse to go cater to my filthy addiction outside on the corner for a minute."