"My body wasn't warming up like everyone else's. My teeth would chatter, my lips would turn blue. I didn't think it was a big deal, I thought it was just me," Jacqueline said.
She still swims in the cold Melbourne ocean every morning and learned to pack a big bag of clothes to warm herself up afterwards.
"I'd have to have leggings, then tracksuit pants over the leggings and long socks, a T-shirt, then a long sleeved fleece top and a big ski jacket. Even if I had gloves and socks on, my hands and feed would still be cold, they'd be icy," Jacqueline said.
"There were times when I'd be working in my office and I would be so cold that I'd be wearing my ski gear inside on a 30 degree day," she said.
"If it was really cold in the evening and I was at a party, I'd just want to get home. In some situations I was just so uncomfortable. That can have an impact on your social life."
Things got so bad that she had to "thaw out" in a hot bath every morning after her swim.
"My the time I did that and got around to starting work, it would be quite late in the day. I thought 'This is not right. My thermostat must be out of whack'," she said.
Our body temperature is controlled by a part of the brain called the hypothalamus, which also controls weight and hormones.
"We know that people with a disrupted hypothalamus can sometimes have difficulty controlling their body temperature," said Professor Joseph Proietto, an endocrine specialist from the University of Melbourne.
"It's quite difficult to treat. The brain doesn't know what's a normal temperature and can't regulate itself," Prof Proietto said.
Professor Michael Cowley, head of physiology at Monash University, says there could be a number of reasons why Jacqueline's body behaved this way.
"Changes in the way this part of the brain works can cause changes in body temperature, but it's important that with any condition like this you see a qualified health professional, because there can be other causes," Professor Cowley said.
Jacqueline said she consulted a natural health specialist who prescribed her a series of herbs and natural medicines, as well as a detox diet. She also cannot have cold drinks or drinks containing ice.
"Within a month, I wasn't cold anymore," Jacqueline said.
"I was so warm, my teeth were no longer chattering, my lips were no longer blue and I could sit around with normal clothes on instead of so many layers. I didn't need a hot bath.
"Everyday I am still going into the water, but I'm not freezing and I just put my tracksuit on afterwards. It's just remarkable the difference in how warm I am."
Prof Proietto says anyone experiencing similar symptoms should visit their local GP.
