Shivering in the chill room could be the next big thing for
After 15 minutes of cold your body will be pumping out two
hormones that could turn unhealthy white fat into
energy-burning brown fat.
That's the theory behind Australian scientist Dr Paul Lee's
research published in the journal Cell Metabolism.
Dr Lee has just returned from the US where he conducted human
trials that show shivering and moderate exercise produce the
same energy-burning hormones.
He has also conducted laboratory experiments that show the
hormones are able to turn human white fat cells into healthy
brown fat cells.
Until a few years ago it was thought brown fat was found only
in newborn babies to keep them warm, he says.
But research has shown adults retain brown fat. In babies it
is mostly around the upper back and shoulders and in adults
it is around the neck.
"The more brown fat an adult has, the leaner they are and the
lower their blood sugar is," said Dr Lee, from Sydney's
Garvan Institute of Medical Research.
"If we can increase the amount of brown fat in the body, it
may protect people from gaining weight and developing
Dr Lee's study has shown that shivering for 10 minutes to 15
minutes at 14C to 16C has similar hormone-producing results
to an hour of moderate cycling.
There were also benefits at a less chilly 19C, he said,
emphasising more research was needed to determine safe and
effective levels of exposure.
"Our results showed that moderate exposure to cold may be
helpful, but the importance of a healthy diet and regular
exercise should not be neglected."
Dr Lee was optimistic his work could add a new dimension to
the battle against diabetes and other diseases.
Endocrinology professor Don Chisholm of Garvan and St
Vincent's Hospital in Sydney says the cold is a strong
activator of brown fat, but modern humans might have lost its
effect because we no longer get cold.
"Brown fat is very healthy. It helps burn up calories and
"A question is whether we can find pharmacological or
lifestyle methods to activate brown fat."