Carrie Underwood Debuts Dramatic New Hair Color While Supporting St. Jude

Carrie Underwood revealed a dramatic hair transformation in a new

post.

Underwood, 42, shared a selfie wearing a t-shirt in honor of St. Jude’s on Friday, Dec. 12 — and she revealed her new brunette hair.

“Every child deserves hope.  Become a Partner in Hope with@stjudeand get your@musicgivesshirt at musicgives.org and help kids facing cancer. ❤️,” Underwood wrote in the caption.

The country star, known for her blonde locks throughout her career, made the reveal while wearing a black-and-white t-shirt that read “Music Gives to St. Jude’s Kids.” Fans of the “Before He Cheats” singer were shocked at the hair transformation in the comments.

“Didn’t even look like Carrie,” one Instagram user wrote.

Underwood previously tested out going brunette in August, before ultimately returning to the blonde tresses that she has had since herAmerican Idoldays. Underwood shared the

on Aug. 5, and explained at the time that she hadn’t been brunette in 30 years.

“Well, the last time I saw my natural hair color, I was probably about 12 years old,” the Grammy winner wrote, “but I thought it might be time to give it a second chance.”

Underwood had an assist from Nashville hairstylist Katelin Megert, who cut, colored and styled her hair into a brown mid-length cut with golden highlighted layers.

“Thanks,@hairbykatelin_at@parlour3beautyfor helping me get back to my roots!#NewOldMe#Bronde,” she added.

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In a 2012 interview with Refinery29Underwood explained her reasoning for always being blonde. Despite wanting to experiment with her hair color, she felt it was tethered to her music career at the time.

“I’d love to do a little with hair color. I’ve always been blonde! The problem is, I don’t want to shock people — like if I dyed my hair brown, I don’t want people think I’m turning dark and serious. I wish I had started changing my hair around in the beginning, then it wouldn’t be such a big shock if I did something like that now,” she said.

Underwood will soon join Alan Jackson on tour.