The shocking reason behind Survivor NZ contestant's huge 18kg weight loss

Adam O’Brien was the latest contestant to join the jury on Survivor NZ.

Catching up with the show’s host Matt Chisholm and Estelle Clifford, Adam revealed something truly shocking about his time on the game.

He didn’t go to the bathroom for 22 days!

"I was quite fat when I started, I was quite chubby, I was like 105kgs. So, you know, I had a lot of fat stored up to call energy upon and I think that’s just what happened," Adam admitted.

"I didn’t go toilet for a while either, so my body probably just stored everything I had and all the rewards."

Adam – who dropped a massive 18kgs while competing in Thailand – says he "could see [his] whole Survivor journey" in the toilet once he finally did relieve himself.

Thanks for that visual, Adam …

Speaking more about the weight he dropped - Adam noted to Estelle and Matt that he "couldn't believe it".

The Survivor star also took to Instagram to share the way his body had transformed.

• READ MORE: How this Survivor star fell victim to the show's most epic blindside

"I lost 18kg," he wrote alongside a before and after photos.

"Day before I flew to Thailand [on the left], night I was eliminated [on the right]! Thank you, everyone, for your support! I’ve had the best time of my life playing."

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