In their report, Dr. Cypess and his colleagues reviewed 3,640 PET-CT scans performed on 1,972 patients at Beth Israel Deaconess Medical Center in Boston for various diagnostic reasons. Among women, 7.5% had patches of brown fat that were more than 4 millimeters in diameter, while 3.1% of men had similar patches.
“The people who had brown fat were, in fact, different from the people who didn’t,” Dr. Cypess explains: They were younger and leaner. People who were older, those who were obese, and those using heart drugs called beta blockers were less likely to have brown fat.
Dr. Cypess and his team also found that people whose scans were done in the winter had the most brown fat, while those scanned in the summer had the least; people who underwent the tests in the spring or fall fell in the middle.
Researchers from the Maastricht University Medical Center in the Netherlands, in the second study, looked at how temperature affected brown fat activity in 24 healthy men, also using PET-CT. When the volunteers sat in a room kept at 72° F for two hours, none of their scans showed brown fat activity. But when they were exposed to slightly chillier conditions—about 61° F—23 showed brown fat activity. The 10 men who were lean (with body mass indexes of less than 25) had more brown fat than the 14 who were overweight or obese, and their brown fat was also more active.
“That’s really new, that so many people do have brown adipose tissue,” says lead author Wouter D. van Marken Lichtenbelt, PhD.
In the third study, Sven Enerback, MD, of the University of Goteborg in Sweden, used PET to examine how cold temperatures affected brown fat activity, this time in five people. Participants spent two hours in a room kept at 63° F to 66° F. During the scan, they submerged one foot in ice water, alternating five minutes in the water and five minutes out. The cold conditions boosted the amount of glucose the study participants’ brown fat consumed by a factor of 15.
In an accompanying editorial, Francesco Celi, MD, of the National Institute of Diabetes and Digestive and Kidney Diseases in Bethesda, Md., notes that “taken together, these studies point to a potential ‘natural’ intervention to stimulate energy expenditure: Turn down the heat and burn calories (and reduce the carbon footprint in the process).”
This is obviously an oversimplification, Dr. Celi says, but the demonstration that adults have brown fat that can be activated is, nevertheless, “powerful proof of concept” that the tissue could be a target for obesity-fighting drugs or even environmental fat-fighting strategies.
While Dr. Cypess is excited about the possibility of drugs that help people burn more calories, he warns that such medicines wouldn’t allow people to slim down without eating healthy and becoming more active.
The maximum amount of extra energy that people with relatively large brown fat deposits can burn probably tops out at about 500 calories. “It doesn’t take much extra food to eliminate any benefit you’ve got,” he says. “I personally don’t think that hanging out in the cold is going to be an effective way of fighting obesity.”
Comments (11)
“Turn down the heat and burn calories”. Yeah, that’ll work — just as well as asking Americans in the 70′s to turn down the heat and wear a sweater to save energy.
The last 30 years have proven that Americans will not change behavior to solve their problems. The pattern is getting worse, not better.
Craig in Seattle
I just tested a product by Bodywell Nutrition called Top Secret. It targets triggering the brown fat and I had never heard of such a thing. Now that I read this article I understand what they were talking about. It worked for me.
It’s been known for decades that brown fat grows in adults exposed to colder environments. In fact, back in the 1970′s I went through a phase in which I jogged on cold winter days in order to alter the proportion of brown fat my body made based on the science media hype about it then.
The only new news I can detect here is the identification of some protein which may regulate that proportion. Practically though, it will probably (always) be a lot cheaper for most people to get more of it just by turning down the thermostat rather than invest in some expensive gene or protein therapy. And exercise is effective in reducing all fat, no matter what color it is, or the temperature outside.
>Craig End says:
>The last 30 years have proven that Americans will not change behavior to solve their problems
Generalize much?? How about recycling?? People predicted American’s would not recycle. Now almost all communities (at least in the east) have recycling programs and a lot of states have bottle bills that are well participated in. I remember as a kid seeing trash and bottles everywhere around streets and highways. You just don’t see that anymore. And what about what happened with gas prices last fall… Prices went up and so many people curtailed usage that the prices dived and inventories rose. Gas is just now getting back up to $2. Americans will change if it makes sense and they are properly incentivized.
Rob, I don’t think recycling solves someone’s personal problems. I think Craig is saying that in general, Americans are lazy at solving their personal problems.
I agree with Craig and Sophie.
For example: stop reading articles about increasing brown fat, stop eating garbage, and exercise from time to time. Those seem like behavioral changes that would solve health problems for millions of obese Americans. Not going to happen without some serious changes to how people think.
I think that most Americans are not lazy about solving problems, they are simply lazy about being informed on HOW to solve problems. They are also poorly informed about the existence of those problems. With all of the media hype about things that rarely amount to anything personally important, its no wonder Americans ignore most of what they hear and wait until it directly impacts their life before they believe what they hear and see in the media. With all the mis-information and slanted information at our finger tips its hard to know what to believe…making it hard to care about the same things.
This article is quite interesting and infact its very known in Sweden that even in the kindergardens we usually leave the kids sleeping in their buggies for like an hour or so in the cold in order for them to be capable of keeping their brown fat, what i was wondering if the brown fat proportions are somewhat the same in people born/bred in cold countries vs. those born/bred in hot environments. for example what if someone born in Africa and lived their childhood their, then they move to a cold country, would they have any brown fat left? or would have they lost it completely? can you reactivate it?
Guess we know why those Canadians are so skinny now, eh?
I am intriqued about Brown Fat; it is an corridor of Health awareness. I can sleep in a cold room, but walking around in a cold house is difficult, I am prone to arthitis; but I feel so refreshed upon waking up in the morning. Please More tips on the Brown fat.
brown fat for a healthy life.