The 21-year-old student from Darwin, who lost 31.6kg during her time in the weight loss competition, was eliminated after asking her white teammates to vote her out.
The entire team, consisting of Brown, Michelle Cortesao, Kasey Cheesman and former red team member Margie Cummins, went into the elimination room after losing a challenge.
Cummins said: "I'm so angry right now. I can't describe how angry I am. I was taken from my red team and placed with the white team. My training with [instructor] Tiffiny [Hall] has been quite disruptive because Selena can't get her head right. I've lost 5kg and yet I'm here at elimination. It's been the worst week."
Despite Hall begging Brown to give the show a chance, she asked the other three contestants to vote her out because she was missing her family and home.
Cortesao admitted that Cummins was "definitely the biggest threat" but still voted for Brown to leave The Biggest Loser competition. Cummins also voted for Brown, resulting in her elimination.
Brown said: "I'm sad about going home. I'm going to miss everyone here. What I've learned in the past few weeks I wouldn't have learned on the outside. I've got the confidence to do it. I'm a lot happier."
Brown was actually the first contestant to be eliminated from The Biggest Loser, but she was brought back in a shock twist a few days later.
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