He slimmed down with daily gym work and by partaking in the SASS Fit programme at CLM, a fitness regime that involves functional fitness, and cardio circuits, similar to CrossFit.
But he wasn't always the picture of health.
"I started drinking when I was in my 20s and got into DJing so that sort of lifestyle took over," Mr Kerehi said.
"It was my life for 18 years - touring, doing gigs, eating all the time on the road, drinking... it catches up with you and takes a toll."
He said there was a day about four years ago that he was so heavy and unfit he struggled to walk to a dairy only 50m down the road.
"I was thinking, man what happened to me?"
That same day, Mr Kerehi's aunty and CLM gym coordinator, Tania Karaitiana, offered a hand to help him shed the weight.
"It was like it was meant to be," he said.
"She asked me when I wanted to start and I said, tomorrow."
It took Mr Kerehi a year of hard work to lose more than 50kg, and he has maintained a healthy weight for three years since.
"I found the hardest part was walking into a gym, feeling like everyone is looking at you.
"But you've got to put that aside and just think of yourself and just start.
The biggest obstacle in life is yourself, nothing else - you are in control of everything."
In the three years following his dramatic weight loss, Mr Kerehi has been considering skin removal surgery so he can "finally take [his] top off".
"I'm reminded of the old me every time I get out of the shower and I feel like my journey is not finished until the loose skin is taken care of."
Tummy tuck surgery in New Zealand would cost around $25,000, Mr Kerehi said, a price he thinks is "ridiculous".
"Why doesn't the government help people that are actually doing something to not be obese and stuck in hospital using taxpayers' money?
"There are people out there trying to turn their lives around - [the government] should subsidise the surgery so it's affordable."
Because of the hefty price tag, Mr Kerehi has opted to have his surgery done in Thailand and is booked in to have two procedures done in March for a total of $18000, including flights and six nights in hospital to recover.
Mr Kerehi has raised most of the money himself by selling about 150 pairs of shoes from his prized sneaker collection, and he is hoping the community can help him make up the difference through a Givealittle page, his friends and family have helped set up.
For more information or to donate, visit givealittle.co.nz/cause/jermaine2thailand.
