The 42-year-old told People that he was disappointed when he had to change his appearance for a movie recently.
"They dyed the grey out for We Bought A Zoo, but I was like, 'I like my grey hair!'" he said. "I'm proud of it."
Damon also revealed that his hair has become the subject of jokes with his four daughters Isabella, Gia, Stella and Alexia.
"I point out all of the grey and I say to my daughters, 'You did this and you did this and you did this'," he explained. "They really think it's funny."
Damon reportedly recently got 'spanked' at his 42nd birthday party in London.
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