The actor filmed a full-frontal nudity scene in 2008 comedy Forgetting Sarah Marshall
Asked if fans shout movie quotes at him in the street, Segel told ShortList: "Paul Rudd gets 'Slappa da bass'.
"I get, 'Hey, it's Sarah Marshall - show your d**k!' Super-awkward when you're with your parents."
Segel added of the scene: "That was a very specific choice and it wasn't for shock value. That scene is meant to be dramatic, but you're watching a comedy.
"If there was no nudity in that scene, it's a drama scene. But I thought, 'Any time it feels a little too intense, let's just cut to my penis'."
American Reunion star Jason Biggs recently quipped that Segel "just loves flumping his [penis]" in movies.
> Jason Segel on Sarah Marshall nude scene: 'People laughed or threw up'
Watch the Forgetting Sarah Marshall trailer below: