How Your Body’s Heater – Brown Fat – Works

Believe it or not, your body has an organ that serves as an efficient little heater. It’s brown fat. Obesity geeks might call it brown adipose tissue. Or BAT for short. For some time now, BAT has fascinated obesity scientists. Adding to their excitement is a new study last week in Nature. The research documents how BAT works not only to burn calories and generate heat. But it also clears a type of amino acids that play a role in obesity and diabetes.

Branched-Chain Amino Acids: Too Much of a Good Thing

Branched-chain amino acids (BCAAs) can be quite helpful for healthy muscles. But too much of a good thing is a bad thing. And in the case of BCAAs, too much of them is linked to obesity and diabetes.

In fact, recent research shows that reducing excessive BCAA levels might serve to treat diabetes. It’s animal research, but it serves well as a proof of concept. Indeed, it may lead to new diabetes treatments.

Burning Off Excessive BCAAs

The latest research in Nature tells us that brown fat uses BCAAs as fuel for producing heat. When it’s working right, BAT burns off excessive levels of BCAAs that might otherwise contribute to obesity and diabetes.

Researchers led by Takeshi Yoneshiro showed that persons with more brown fat cleared more BCAAs from their bloodstream when exposed to cold. Under the same conditions, persons with less brown fat did not. Those researchers also demonstrated how this works in mice. They found a protein – SLC25A44 – that serves to transport the BCAAs into the mitochondria of brown fat cells. That’s where the brown fat cells break down the BCAAs to produce heat.

You might call it a two-for-one deal. Brown fat is ridding the body of too much BCAAs. And at the same time, it’s producing heat and promoting metabolic health.

In more ways than one, this continues to be a hot topic. Brown fat is a target for new obesity and diabetes treatments. Even so, the way forward will be challenging.

Click here for the study in Nature and here for further perspective.

Heater, photograph © Thomas Hawk / flickr

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August 26, 2019