Why Freezing Yourself Thin Is Problematic

Researchers have linked cold exposure to increased metabolism, but using it for weight loss still carries risks.

Sean Kernan
5 min readDec 4, 2023


people jumping in the ocean
Pexels images via Kindel Media

The worst part of my college experience was getting out of my warm bed at 5 AM, and having to jump into a cold pool just 20 minutes later. It never got any easier. In fact, it got worse as winter came and put snow between me and the aquadome.

One week, our pool’s heating system broke. It wasn’t quite cold enough to rule out swimming, sadly. We were young, fit, and accustomed to dealing with chilly water, but this was an order of magnitude worse. Many of us stood on the edge of the pool deck, staring at the water and contemplating our life choices.

Something peculiar happened that week: my appetite went through the roof. Despite already eating 5,000 calories a day, I was needing more food. The team’s nutritionist said it was likely the changing temperature of the water, and had seen similar trends in prior years when the heater broke. She prescribed me more carbs, and I obliged.

It isn’t breaking news that cold raises your metabolism. Yet it is now the subject of expanding research in the battle against obesity, and promoting good health. A team of researchers, led by Dr. Marc L. Reitman, used intermittent cold exposure on a group of mice. They were kept at four degrees Celsius for eight hours, three times a week. Researchers found that the mice’s metabolic rate was increased by double for this duration, and showed an increase in brown fat. This is significant because brown fat is associated with weight loss, and has an inverse correlation to high BMIs.

Brown fat burns and stores more energy than other types and is kept in a smaller space, packed with iron-rich mitochondria, giving it a darker color than white fat — which is linked to obesity.

However, Dr. Reitman’s study ran into the same problem I faced with swimming: the mice got considerably hungrier and compensated for the increased metabolism by eating more. The scientists suggested that some intervening measure was needed to ensure weight loss actually happened and was sustained.



Sean Kernan

Former financial analyst turned writer. Always on the hunt for a good story. That guy from Quora. Writing out of Tampa, Florida.