LOS ANGELES (CBS) —  Some say the thermal diet or cold exposure can help you keep unwanted fat off.

Busy mom Gillian Hobson is like many of us, she’ll do almost anything to lose weight and keep it off. She says, “I’ve tried quite a few.”

But can she handle what Tim Ferris does? Three times a week he takes an ice bath…2 ten pound bags of ice for about 15 minutes, never putting his hands or head in the water. He calls it thermal loading, exposing himself to the exteme, extreme cold that is…. to keep his body super lean.

He says, “I’ll sit in the ice bath up to my waist for about 10 minutes also reading a book or magazine and then for the last few minutes go up to the neck with the hands out of the water.

Ferris, is the author of the ”4 Hour Body.” He says this will help you lose unwanted fat.

“So your body wants to be at 98.6 degrees and if your body temperature is lower it will do almost everything it can to get back to the 98.6 degreess and it burns calories as heat and most of the calories come from fat. The body burns more fat to make itself warmer, the lower your body temperature you’re going to burn more fat.”

Ferris says don’t go to the extreme at first. Start with ice packs on the back of your neck for about 5 to ten minutes. Then move to cold showers for at least 5 minutes, and if you can tolerate that, on to short ice baths. He warns anyone with health problems should not do this or talk to their doctor.

Now, Tim Ferris says he came upon this chilling theory by accident. He says, “I was using ice baths initially for sports recovery and I noticed accelerated fat loss, and then I met Ray, this former NASA scientist. He really had all the science to show that this is why cold helps you lose fat.”

Ray Cronise lost 30 pounds in 5 weeks by adding cold to his diet and exercise regimine. He says the aerospace industry has studied the effects of cold for decades…and learned metabolism jumped when people were exposed to cooler temperatures. So he worked out in cooler temps..wore less layers through the day, turned down the thermostat…slept without covers…and would take walks without bundling up.

But is this a quick fix, a prescription for a magic solution? — Dr. Raluca Arimie of Northridge Hospital Medical Center says the science behind this sounds interesting but…”cold can affect people with heart conditions and is not good for everyone. Always talk to your doctor before trying anything.”

And Ferris agrees this is not for everyone but after his 3 year quest for the 4 hour body…he’s sold on the cold. As for Gillian not yet, but she’ll try to add a little to her diet to see how it works.

Lisa Sigell, CBS 2 News

For more information about “4 Hour Body,” click here: http://fourhourbody.com/

For more information about hypothermics, click on the following: http://hypothermics.com/about/