The hunky 29-year-old actor - who plays the titular superhero in the `Captain America` movie - is losing his hair and is worried people won`t take his character seriously if he is bald in the planned sequels.
He told E! news: "I have no problem saying this, but I`m losing my hair.
"The fear is this [role] can span 10 years so I can be doing this character until I`m 40. I`m supposed to be like this superior human. He can`t be balding. How horrible would it be if this superior man has male pattern baldness?"
Although he can`t control his hair loss, Chris revealed he is a gym addict and feels like "s**t" if he doesn`t work out almost every day.
He said: "It`s a lot more than I`d like it to be, but you know, if I miss three or four days, I feel like s**t.
"Last year, I got into running and I was like, `I`m going to start running` and then I would run on the treadmill and feel great. But I`ll get too thin. I lose weight so quickly."