Natural Fat Burns calories – new way of fighting obesity
Imagine having a unique kind of fat in your organism that actually burned calories instead of accumulation and it could be turned on just by spending your time in the cold environment. Three preliminary studies published Wednesday in the NEJM (New England Journal of Medicine) show that human body probably does have such fat called “brown fat”.
Brown adipose tissue – that’s what helps young children, babies, other small mammals to stay warm. The brown fat burns calories when it’s activated by cold temperatures. Before, scientists were skeptical that adult human body has any amounts of brown fat left in organism. But now research shows that most of adults have significant amounts of it.
“The incredible excitement about this research is that we have an entirely new way to fight obesity,” said Dr. Aaron Cypess of the Joslin Diabetes Center in Boston, MA, the lead author of one of the new studies. In fact, today’s popular diet pills help people to consume less calories, Cypress said. But new researches show that new drugs may be developed that will accelerate brown fat activity and will lead to fast and natural weight loss.
New research confirms that adult individuals have brown fat involved in temperature regulation, while also playing a role in whether person is lean or overweight, said Jan Nedergaard, professor at the Wenner-Gren Institute at the University of Stockholm in Sweden. Jan has been studying brown fat for about 30 years, but wasn’t involved in recent research.
“Individuals who had brown fat were, in fact, different from the people who didn’t,” Cypess explained: They were younger and leaner. Individuals who were older, those who were obese, and those using heart drugs called beta blockers were less likely to have brown fat.
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,” said lead author Wouter D. van Marken Lichtenbelt.
In the third study, Dr. Sven Enerback, 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, Dr. Francesco Celi, of the National Institute of Diabetes and Digestive and Kidney Diseases in Bethesda, Maryland, noted 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, Celi said, 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 Cypess is excited about the possibility of drugs that help people burn more calories, he warned 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 said. “I personally don’t think that hanging out in the cold is going to be an effective way of fighting obesity.”
