If you don't mind the cold and are happy to shiver off a few pounds, then a new jacket designed by NASA scientists could be the weight loss method of your dreams.
The Cold Shoulder jacket is a human cooling device, filled with ice, which can help wearers burn calories simply by wearing it for a few hours each day.
The waistcoat helps the body burn up to 500 calories per day by using comfortable, mild cold exposure to activate your metabolism, which then burns fat as the day goes on.
Dr Wayne B. Hayes, who is professor at the University of California and a visiting scientist at NASA's Jet Propulsion Laboratory, says that by simply wearing the jacket - and not exercising - users can burn up to a pound of fat each week.
The waistcoat can be stored in a freezer to keep it chilled. Then, when wearers put it on they are encouraged to sit in a comfortable temperature and let the wasitcoat work its magic.
The scientist adds that it will extract heat from the body and cause extra calories to be burnt because you're trying to keep warm. They also claim that the jacket is 70% faster at burning fat than dieting alone.
"Scientists have spent decades studying how mild cold exposure can enhance calorie burn and the evidence has been accumulating,” said Dr Hayes.
“The goal of the Cold Shoulder is to force you to burn calories at a time when you otherwise would not: sitting down, at rest, in a comfortable environment at room temperature."
Sounds snazzy - so where can you buy one?
The jacket is currently being crowdfunded on Kick Starter and has far exceeded its original target of $13,500. It costs $160 and will be available in sizes XS to XXXL.
While we wouldn't mind wearing this in the height of summer (who needs air con?), we couldn't think of anything worse than wearing such a frosty little fashion item right now.