Chill Out (Literally) & Trigger a Higher Calorie Burn

posted Feb 8, 2015, 6:46 AM by Walk Strong Calgary   [ updated Mar 1, 2015, 6:36 AM ]
Body Fat - Brown vs. White                            
- by Nancy G Ehle

I remember an episode of 'Little House on the Prairie' wherein Mrs. Oleson refused to pay the same price for brown eggs as white, feeling the former were inferior. In reality, the only difference is the shell color, which is determined by genetics of the birds and has no impact on nutritional content according to

When it comes to body fat, however, there is a marked difference between brown and white. While white fat stores excess energy for use as fuel, brown fat generates heat in the body to keep us warm, a process called 'non-shivering thermogenesis,' leading to increased calorie burn.

Unlike white fat, the brown variety is active, using up calories to keep the body warm. This could prove advantageous during our cold Canadian winters... well, cold winters anywhere, truth be told. Exposure to the cold increases levels of a protein in the body that plays a major role in brown fat formation according to researchers at the University of California, Berkeley. Results of a study published in the on-line journal 'Molecular Cell' indicate that extended exposure to cold can actually cause white fat to take on characteristics similar to brown fat, burning more energy. There is evidence that brown fat may also have a favorable impact on metabolism and insulin resistance according to Hei Sook Sul, UC Berkeley professor of nutritional science and toxicology.

Overall, the percentage of brown fat in our bodies is quite small (10% compared to 90% white), and as adults, our need for brown fat has decreased over time due to spending the majority of our lives in controlled environments. Outdoor workers
have been found to have significantly higher concentrations of brown fat when compared with indoor workers of the same age, according to Sul. There is a particular protein found only in the mitochondria (generators of ATP for energy) of brown fat - this protein is involved in heat generation. As heat is generated, both fat and glucose are burned. 

Throw on your winter boots, gloves, head cozy (toque) and parka and get a good brisk outdoor walk in, in spite of the cold - you'll kick the fat burning in your body up a notch! Just watch out for those icy patches... 

 Walk safely out there!

Nancy G Ehle is an ACE Certified Group Fitness Instructor & Certified WALK Leader (Leslie Sansone). She also holds certifications in Sports Nutrition, Pilates, and as a Health Coach. She has a published science fiction novel to her credit (The Timekeepers: Book I - A Play for Time) and is known for her attention to detail where research is concerned. Follow Nancy on Twitter and  Facebook!