In order to understand whether whole-body cryotherapy can cause brown fat activation, it’s necessary first to look at fat in general. In the human body, fat serves three vital functions. First, it is a critical source of fuel when your metabolism cannot find carbohydrates. Second, vitamins A, D, E, and K are fat-soluble, and fat is necessary for their absorption. Without it, you would have vitamin deficiencies. Third, fat is insulation — it helps preserve your core temperature when you get cold.
But there’s a fourth function of fat, and it requires a specialized type of fat: brown adipose tissue (BAT) or simply brown fat. Most fat is white, and white fat is pretty good at accomplishing the three health functions listed above. Brown fat, on the other hand, is a different kind of fat altogether. Unlike white fat, brown fat doesn’t supply calories. It burns them. Brown fat is most abundant in infants. It is less prevalent in adults.
Brown Fat in Human Development
Brown fat’s presence in infants suggests its raison d’être. Infants are unable to shiver, which means they lack a fundamental means of thermoregulation. For them, brown fat’s ability to burn calories in response to cold is a survival mechanism. In the words of a 2009 study in the journal Diabetes, “The sensation of cold causes sympathetic nerves to release catecholamines in BAT that stimulate proliferation and heat production by brown fat cells.”
As you grow, you acquire the ability to shiver, and shivering burns the calories (and creates the heat) for you. In addition, life tends to add to your stock of insulating white fat, so it takes longer for you to get cold. As an adult, you don’t need the brown fat quite as much as an infant does. That may be why brown fat is more scarce in adults than in infants. Nevertheless, a number of studies — reported in an article in The New York Times — have shown that nearly everybody has some brown fat, and that it can be activated by cold. That same article reported on a study that showed mice that were predisposed to obesity, when placed in a cold room for a week, lost 14% of their body weight (47% of their fat), even while eating a high-fat diet.
Speculation Based on Science
Here are three things that have been proved by science about brown fat: 1) human adults have brown fat, 2) brown fat burns calories prodigiously when activated, and 3) brown fat can be activated by cold temperature. Here’s a speculation that I think is warranted by what’s been proved: exposing yourself to cold can activate your brown fat and help you lose weight. In fact, some studies mentioned in that New York Times article showed that sitting people in cold rooms (about 60 degrees) activated their brown fat, although weight loss was not generally measured.
The idea that human adults could lose weight by activating their brown fat with cold temperatures is speculative. But it seems solid enough that if you have a weight problem, you might try turning down your thermostat to 60 degrees. Or you might try whole-body cryotherapy (WBC). I have found no studies that show WBC activates brown fat the way sitting in a moderately cold room does. But I have run across a number of pronouncements about it, mostly from WBC boosters.
Test It Yourself
You don’t need to know whether the statements of WBC boosters are credible, however, if you just want to try it for yourself. Book yourself a course of whole-body cryotherapy sessions — say twice a week for three weeks — at Peak Recovery & Health Center. Hold diet and exercise constant during the three weeks, and see if you have lost any weight by the end of the test. We have a number of customers who say they have lost weight that way, but that’s anecdotal. The way to find out is test it for yourself.