Science

First-of-its-kind study links brown fat with broad health benefits

First-of-its-kind study links ...
Analysis of PET scans from more than 50,000 subjects found detectable brown fat levels correlated with better metabolic and cardiac health
Analysis of PET scans from more than 50,000 subjects found detectable brown fat levels correlated with better metabolic and cardiac health
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Analysis of PET scans from more than 50,000 subjects found detectable brown fat levels correlated with better metabolic and cardiac health
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Analysis of PET scans from more than 50,000 subjects found detectable brown fat levels correlated with better metabolic and cardiac health
In these PET scans, the person on the left has abundant brown fat around the neck and cervical spine, while the person on the right has no detectable brown fat
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In these PET scans, the person on the left has abundant brown fat around the neck and cervical spine, while the person on the right has no detectable brown fat

A new study, the largest of its kind ever conducted in humans, has affirmed the link between the presence of brown fat and improved cardiac or metabolic health. The research validates the relatively new hypothesis suggesting the type of adipose tissue commonly referred to as brown fat confers broad health benefits.

The body harbors a few different kinds of fat tissue, but the most common is known as white fat. These are the fat cells we all try to get rid off and they're the type that comprise the vast majority of fat cells in our body.

Brown fat on the other hand is commonly thought to be much more metabolically active, being composed of higher amounts of iron-rich mitochondria that allows the body to rapidly burn it off. Brown fat is found in high volumes in babies, but until very recently it was thought we lost the capacity to generate it as we grew older.

In 2009, researchers discovered brown fat is still present in adults in small amounts. This discovery prompted a flurry of work investigating ways to turn white fat brown as treatment for obesity and other metabolic disorders.

One challenge slowing down research into the possible beneficial effects of brown fat has been the difficulty in detecting this particular kind of adipose tissue. Tobias Becher, first author on the new study, says brown fat is only detectable using PET scans, making it challenging to conduct mass population studies.

"These scans are expensive, but more importantly, they use radiation," says Becher. "We don't want to subject many healthy people to that."

So in order to get an insight into the effects of brown fat on a large population scale the researchers looked at data from more than 50,000 patients who had undergone PET scans for routine cancer evaluation. After adjusting for the influence of individual cancer types and stages, the researchers could effectively correlate the presence of brown fat with a number of cardio-metabolic conditions.

In these PET scans, the person on the left has abundant brown fat around the neck and cervical spine, while the person on the right has no detectable brown fat
In these PET scans, the person on the left has abundant brown fat around the neck and cervical spine, while the person on the right has no detectable brown fat

The results confirmed the presence of brown fat was associated with a lower prevalence of several chronic diseases. Those subjects with brown fat present were significantly less likely to have type 2 diabetes. Brown fat was also associated with lower levels of hypertension and coronary artery disease.

“While obesity is generally associated with decreased brown fat function, those obese individuals who retain brown fat activity appear to be protected against conditions linked to excess weight,” the researchers write in the newly published study. “This notion further supports the potential of brown fat as a therapeutic target beyond weight loss itself, but as a means to uncouple obesity from disease.”

While scientists know brown fat is much more rapidly utilized as an energy source by the body, it is still unclear how it may be generating broader health benefits. The association with lower rates of hypertension is one finding suggesting brown fat could be doing more than simply burning calories faster than white fat.

"We are considering the possibility that brown fat tissue does more than consume glucose and burn calories, and perhaps actually participates in hormonal signaling to other organs," explains Paul Cohen, another researcher working on the new study.

A large volume of research over the last few years has focused on finding ways to either stimulate the body to produce more brown fat, or turn pre-existing white fat into its more metabolically beneficial cousin. Proposed methods span everything from hormones that mimic exercise, nanoparticle injections, drugs and even gene therapies that could act like a "fat switch."

"The natural question that everybody has is, 'What can I do to get more brown fat?'" asks Cohen. "We don't have a good answer to that yet, but it will be an exciting space for scientists to explore in the upcoming years."

The new study was published in the journal Nature Medicine.

Source: Rockefeller University

4 comments
4 comments
Chris Coles
Everyone seems to be trying, at last, to catch up on the teachings; Take Control of Your Health, by Dr. Joseph Mercola, where brown fat has been on message for many years now.
N Buxton
As one who apparently has 'active' brown fat, I take an active interest in any news about it, but I would like to warn people it is not necessarily a wonderful thing. Yes, I must be burning calories like mad, but so much heat is generated under my shoulder blades that sometimes it feels like serious sunburn. Probably my biggest problem is that I find it difficult to stay comfortable in bed because my back is so hot and staying cool enough to sleep is a problem. The only plus is that I can venture out in very cold weather without the need to wear a warm coat, but looking bizarre for needing gloves for the hands!

So pursue the idea of brown fat if you want, but it does bring its own problems.
Roy Bermeister
Always understood that brown fat could be increased by extended exposure to 'cold'. Cold air or cold water . The ability to withstand ice temperatures
indicates a healthy dose of brown fat. Tests ought to be done with people from ice cold climates or exposed to 'cold' to prove if this is scientifically correct.
bahbah
Dr Mercola, who does extensive research of medical journals, has stated one of the best ways to convert white fat to brown fat is to subject the body to cold. This is what has been done inadvertently for centuries, but has greatly diminished due to central heating. Best to reduce the thermostat to as low as can be tolerated. Russians regularly dip and swim in ice cold water. They undoubtedly feel better for it, probably due to the increase in brown fat it produces. So reducing the thermostat is good for your health and the planet and the wallet.