By Steve Blechman

The body has two forms of fat - WHITE FAT and BROWN FAT. Brown fat burns calories. The more brown fat you have, the more calories you burn. The capability of harnessing one's own brown fat for fat burning is revolutionary! Learning how to increase brown fat naturally can help you get lean by producing extra brown fat and enhancing and activating existing brown fat (brown adipose tissue, BAT), representing a promising way to burn fat.

Mounting evidence suggests that exposure to cold temperatures can enhance BAT activation and thermogenesis. It can also convert white fat into brown fat and enhance glucose metabolism, insulin sensitivity, and fat metabolism. Cold exposure promotes BAT-induced thermogenesis and energy expenditure. Understanding how to boost metabolism through these methods can be beneficial for weight management.

Male adults exposed to cold via a water-cooled suit for two hours per day, five days per week for four weeks increased brown fat (BAT) volume by 45 percent and resting metabolism by 182 percent— according to a study led by Denis Blondin from the University de Sherbrooke in Sherbrooke, Canada. The human body contains small amounts of fat that converts food energy directly into heat. White fat does the opposite— it stores energy as fat. BAT is an important heat-generating tissue in hibernating animals. It promotes non-shivering thermogenesis, which generates heat and helps animals and humans adapt to the cold. Individual differences in BAT content and activity play important roles in human obesity. Increasing brown fat activation promotes caloric expenditure and fat burning. Cold exposure may be an effective way to reduce body fat.

Other ways to increase cold exposure are to turn down the thermostat, keep the air conditioning at high levels during the summer, try swimming in a cold pool or the ocean, wear less clothing in the winter, and take cold baths/showers. Cold showers are only recommended in healthy individuals, because cold exposure can induce sympathetic nervous system activity, cause vasoconstriction, raise blood pressure in susceptible individuals, and is not recommended for those with cardiovascular disease or hypertension. Another common approach is taking a hot sauna and a cooling bath or shower after the sauna. The sauna has been shown to release growth hormone, which enhances lipolysis and fat oxidation, while the cold exposure will enhance BAT metabolism and increase energy expenditure.

The latest extreme cold exposure trend is "cryotherapy," where you are encased below the neck in a tank that is minus 300 degrees Fahrenheit. These full-body cryotherapy chambers, as they are called, are thought to promote weight loss, pain recovery, mood enhancement and relieve muscle soreness. While celebrity athletes like LeBron James and Shaquille O'Neal have touted the benefits of cryotherapy, there is no scientific evidence to show that cryotherapy increases brown adipose tissue (BAT), thermogenesis and weight loss. A six-month study of moderate aerobic activity combined with whole-body cryotherapy did not see a change in body mass, fat or lean body mass percentages. The experiment was performed on 45 overweight and obese men.

The U.S. Food and Drug Administration (FDA) noted in a 2016 report that while cryotherapy may be a "cool" trend, it poses risk. In fact, some deaths have been reported from using cryotherapy. The FDA report stated: "Given a growing interest from consumers in whole-body cryotherapy, the FDA has informally reviewed the medical literature available on this subject," said Aron Yustein, MD, a medical officer in the FDA's Center for Devices and Radiological Health. "We found very little evidence about its safety or effectiveness in treating the conditions for which it is being promoted."

Cold exposure is not a practical approach for increasing BAT-induced thermogenesis and weight loss for most people, and it may not be pleasant or safe. Diet, exercise, and certain supplements to increase brown fat would be a better approach than cold exposure.

References:

Blondin DP, Daoud A, et al. Four-week cold acclimation in adult humans shifts uncoupling thermogenesis from skeletal muscles to brown adipose tissue. J Physiol 2017; 595: 2099-2113. doi:10.1113/JP273395

Lubkowska A, Dudzinska W, et al. Body composition, lipid profile, adipokine concentration, and antioxidant capacity changes during interventions to treat overweight with exercise programme and whole-body cryostimulation. Oxid Med Cell Longev 2015;803197. doi: 10.1155/2015/803197

Whole Body Cryotherapy (WBC): A "Cool" Trend that Lacks Evidence, Poses Risks

https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm508739.htm

Peake JM, Roberts LA, et al. The effects of cold-water immersion and active recovery on inflammation and cell stress responses in human skeletal muscle after resistance exercise. J Physiol 2017; 595: 695-711. doi:10.1113/JP272881

Obesity Reviews, August 1, 2017. Obesity Reviews, July 14, 2017. Human brown adipose tissue as a target for obesity management; beyond cold-induced thermogenesis. http://onlinelibrary.wiley.com/doi/10.1111/obr.12584/abstract

Obesity Reviews, August 1, 2017. Non-shivering thermogenesis as a mechanism to facilitate sustainable weight loss. http://onlinelibrary.wiley.com/doi/10.1111/obr.12563/full

Obesity Reviews, February 10, 2017. Factors involved in white-to-brown adipose tissue conversion and in thermogenesis: a review. http://onlinelibrary.wiley.com/doi/10.1111/obr.12520/full