Holt told her story as part of an investigation into binge-drinking among young New Zealanders, especially women.
Her revelations were quickly applauded by Survivor host Matt Chisholm, who revealed his own battles with alcohol recently.
Holt, the star of TV shows like Dancing With the Stars and Crowd Goes Wild, has reportedly been sober for two-and-a-half years.
She told Sunday she drank heavily throughout her 20s to "keep up with the boys".
"It was almost, when I was young, a source of pride, (an) 'I can keep up with the boys' mentality," she said.
"I remember doing funnels at parties and thinking that that was really cool, and that I was tough, and I was just like the boys, I could drink just as much and I could be just as raucus."
Holt had previously revealed her issues with alcohol in an in-depth interview with Canvas, telling the Herald publication her biggest low was failing an on-air drug test and being suspended from her radio job.
She told Sunday that despite being sober for two-and-a-half years, "I'm an alcoholic and I go to AA meetings because it's the only way I know I'm going to be able to stay sober".
Since getting sober, she said the changes had been "huge" and her only hopes for the future were that "I'm happy and I've got real relationships and I'm sober".
On the Green Party website, Holt says she wants to "use my voice to bring attention to what we stand for".
* If you or someone you know has a problem with alcohol, call the Alcohol and Drug Helpline on 0800 787 797.
