A major new study has provided strong evidence that people with brown fat are less likely to suffer from a range of health conditions.
“For the first time, it appears to be associated with a lower risk of certain conditions,” said one of the researchers, Rockefeller University Hospital physician Paul Cohen.
“These decisions make us more confident about the ability to target brown fat for therapeutic benefit.”
Brown or brown adipose tissue (BAT) is particularly common in hibernating and newborn mammals. BAT helps mammals regulate temperature – when we are extremely cold, the large amounts of mitochondria found in this type of fatty material burn energy and produce heat. In fact, it is the iron-rich mitochondria that give brown fat its distinctive color.
It wasn’t until 2009 that scientists discovered that some adults have brown fat in the bodies, usually around the neck and shoulders.
Plenty of mouse studies have been done looking at the benefits of brown fat, but in humans the research has been pretty recent. Brown fat seems to improve a person’s metabolism and may even help with weight loss (although the latter may not be so simple).
“Everyone’s natural question is, ‘What can I do to get more brown fat?’ Cohen says.
“We don’t have a good answer to that yet, but it will be an exciting place for scientists to study in the years to come.”
Looking at a large data set of 52,487 participants receiving PET / CT scans for cancer assessment, the team found evidence of brown fat in just under 10 percent of cases (5,070 people).
The researchers believe that this may be an understatement because of the conditions in which the participants were – they were told not to avoid cold exposure, exercise, and caffeine before the scans, and they have all been linked to brown fat activity.
About 4.6 per cent of those with brown fat also had type 2 diabetes, and that figure was 9.5 per cent in the ‘brown fat’ group. A similar result was seen in extreme cholesterol results – 18.9 percent of people with brown fat had excess cholesterol, compared to 22.2 percent of people without brown fat.
Hypertension, congestive heart failure, and coronary artery disease also saw small positive differences in the brown fat vs or brown fat groups.
“These findings were supported by enhanced blood glucose, triglyceride and high-density lipoprotein values,” the team writes in their new paper.
While the numbers here are encouraging, there is still no evidence that brown fat makes you immune to any of these conditions – but there is a link to a lower risk that is worth further investigation.
What was interesting, however, was that brown fat was particularly protective in those who were obese. Those obese patients who had brown fat were as common in these metabolic and heart conditions as non-obese people.
“They almost certainly are protected from the harmful effects of white fat,” Cohen says.
“Taken together, our findings highlight the potential role of BAT in promoting cardiometabolic health,” the researchers note in their paper.
It is important to note that the data with which the researchers worked came from cancer assessments at the Sloan Cancer Kettering Cancer Memory Center, meaning that this is not a representative sample of the general population.
Nonetheless, the study has provided an interesting new insight into the role of brown fat in the human body, and we hope that even more discoveries will be made in the future.
“We are considering the potential for brown fat to do more than consume glucose and burn calories, and may actually play a role in hormonal signaling to other organs, said Cohen.
The research was published in Nature’s cure.