We are constantly bombarded in the news with stories about fat. Our culture seems to have an obsession with it, constantly talking about the obesity epidemic or the rise in type-2 diabetes or other health related consequences. We learn constantly through all of this that fat is bad and we need to get rid of it.
What we don't often hear about however is the flip side, yes fat can be good as well, at least one kind of fat anyway. That brings us to white fat vs. brown fat.
Researchers have known for a long time that babies have a large supply of brown fat (also known as brown adipose tissue), however it appeared that brown adipose tissue disappeared as we grow and by the time we reach adulthood it has completely disappeared. Recently researchers have discovered a surprising thing; adults do have brown fat and they have found it hiding in places that they never thought to look, for instance it can actually be found in white fat.
What is so good about brown fat? It turns out that while white fat tends to build up in our bodies adding unwanted pounds and thereby bringing about all of the nasty side effects of extra weight, brown fat actually helps you to burn off white fat. Yes brown fat helps you to lose weight!
That alone is probably enough to make you want to get more brown fat in your system but brown fat also has other beneficial health effects, for example it is known to be closely related to the development of muscle mass. Also mice who have higher than average amounts of brown fat seem to be resistant to the onset of diabetes and obesity.
This is all great but how can you get more brown fat in your body? Interestingly in mice studies the amount of brown fat depends on genetics, but it does appear at least for many mice exposure to the cold is a way to activate more brown fat.
Brown fat actually utilizes white fat to help maintain body temperature. So when you are in the cold, your brown fat cells are activated and they start burning off the white fat cells to warm your body up. This has actually recently been shown to happen not just in mice but in humans as well (which shouldn't be too surprising since mice bodies are similar to human bodies).
What the researchers discovered in humans was that by having them sit in a room that was at 63 degrees Fahrenheit rather than 70 the people actually burned nearly 200 more calories per hour of the same amount of activity.
A problem that we have is that these types of fat can transfer back and forth between each other. So when you eat that terrible diet of McDonald's every day you are encouraging your body to convert its brown fat cells to white fat cells which is clearly undesirable.
So I guess the moral of this story is stop complaining about north country winters, they are good for you, no really they are, and lay off of the fast food a little and you should be just fine.