Former Bachelor contestant Ali Oetjen explains how the show "messes you around in the head".

Former Bachelor contestant Ali Oetjen has described how appearing on a program like The Bachelor “really does mess you around in the head”.

Oetjen, who appeared on the very first season of The Bachelor Australia with Tim Robards at the helm, told Adelaide’s Mix 102.3’s Jodie & Soda on Wednesday morning contestants are frequently provided with an oversupply of alcohol and rarely make contact with anyone outside the mansion while on the show.

“Being in the house for about two to three months, not being able to speak to anyone else, your mind is completely focused just on this man,” the former contestant told the radio show.

“My advice would be to someone considering going on The Bachelor, make sure you’re in for a mental roller coaster … it’s not all fun and games.”

Oetjen also revealed it didn’t take long for the producers to learn how alcohol could make their power more pronounced, with contestants “drinking so much, all the time”, and subsequently more likely to listen to a producer’s demands.

“They [the producers] did cotton on as the show went on to give us more drinks so that we would relax and we would do more of what the producers asked of us.”

Oetjen added Richie Strahan's season of the show may not have been the only one with contestants finding love with each other, rather than the designated Bachelor himself, conceding there were suspicions two contestants in her own season were getting up to something together.

“Everyone had bunk beds. There were about six huge bedrooms and each had our own bathrooms and each had our own dressing rooms," she told the show.

“We did suspect two girls [were hooking up] because they would always stay in their room and never come out together ... we all thought something was going on.”

And as for whether she would've done it all again - despite the experience being a "roller coaster" - Oetjen revealed she was approached twice to be The Bachelorette and would have "definitely" done it all again if she wasn't in a relationship.

“The head producer actually rang me six to 10 months later [after the first season aired]," adding she would have considered doing it because it made her "so strong as a person, mentally [and] physically".

“In the house you didn’t have to worry about your bills, it was like being at school you didn’t have to worry about anything. I don’t regret going on. I learnt so much about myself.”

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