Christina Aguilera shows off make-under on 'The Voice,' out with boyfriend Matthew Rutler

The Voice mentor Christina Aguilera has taken some hits in the press for her weight gain and trademark Hollywood glamour look, but her new demure look has heads turning!

Aguilera looks as if she slimmed down a bit, and she transformed her bleach-blonde locks into a more chic, polished style. Her extensions seem to be long gone, as her natural hair looks better than ever.

While out to dinner with her boyfriend Matthew Rutler in Los Angeles on Tuesday night, Aguilera, 31, showed off her new look, E! Online reports.

Accompanied by Rutler, Aguilera wore a figure-hugging dress in blue and grey with no cleavage in sight, and her makeup is significantly toned down, Celebuzz reports.

According to The Daily Mail, Aguilera responded to her critics recently when she maintained As long as I'm happy in my own skin, that's all I need, that's all the confirmation I need. I'm happy where I am, I have a boyfriend that loves my body, I love my body, my son is healthy and happy. That's all that matters.

Aguilera debuted her new look on this weeks episode of NBCs The Voice, where she eliminated two singers.

I have a special place in my heart for all of you, but I have to go with my instinct and my gut and my heart, and thats Ashley, she said before eliminating Moses Stone and Sera Hill.