Posted on 04/09/2009 7:11:21 PM PDT by neverdem
For more than 30 years, scientists have been intrigued by brown fat, a cell that acts like a furnace, consuming calories and generating heat. Rodents, unable to shiver effectively to keep warm, use brown fat instead. So do human infants, who do not shiver very well. But it was generally believed that humans lose brown fat after infancy, no longer needing it once the shivering response kicks in.
That belief, three groups of researchers report, is wrong.
Their papers, appearing Thursday in The New England Journal of Medicine, indicate that nearly every adult has little blobs of brown fat that can burn huge numbers of calories when activated by the cold, as when sitting in a chilly room that is between 61 and 66 degrees.
Thinner people appeared to have more brown fat than heavier people; younger people more than older people; people with lower glucose levels, presumably reflecting higher metabolic rates, had more than those whose metabolisms were more sluggish; and women had more than men. People taking beta blockers for high blood pressure or other medical indications had less active brown fat.
“The thing about brown fat is that it takes a very small amount to burn a lot of energy,” said Dr. C. Ronald Kahn, head of the section on obesity and hormone action at the Joslin Diabetes Center in Boston.
The fat really is brown, researchers say, because it is filled with mitochondria, the tiny energy factories of cells. Mitochondria contain iron, giving the tissue a reddish brown color.
The hope is that scientists may find safe ways to turn on peoples’ brown fat, allowing them to lose weight by burning more calories. But researchers caution that while mice lose weight if they activate brown fat, it is not clear that people would shed pounds...
(Excerpt) Read more at nytimes.com ...
They have brown adipose tissue in the titles.
I must have a very light brown fat.
I’ll have the brown fat.
Hrm.
In an ironic twist of fate people may go from getting rid of fat via liposuction to getting rid of fat via lipoinjection.
So if we freeze fat people, they will shiver and lose weight?
I probably don’t have much brown fat. I get cold and I never have any energy, even when I do physical activity. Like I don’t know how I biked almost 13 miles feeling tired.
This article makes no sense to me.
I was always under the impression that brown fat was the fat inside your abdominal cavity...the stuff that surrounds your organs. This stuff is supposed to be bad for you. It jacks up your cholesterol and blood pressure. And men are supposed to have more of it than women.
Totally opposite of what this article is saying.
Another reason that a person with low blood pressure and too much weight should not be on a beta blocker.
LOL
This might explain why when I go to the Arctic, I actually lose weight; even if I eat a little more than I normally would eat when living in the south.
Time to crank the a/c down this summer!
That's white adipose tissue.
Researchers Find "Good" Fat in Human Adults
FReepmail me if you want on or off the diabetes ping list.
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