Until relatively recently, we thought body fat was an inert energy depot. We now see adipose tissue as a pivotal endocrine organ that can help or hurt you. Fat secretes molecules like leptin that regulate appetite and metabolism. Excess fat is a primary cause of inflammation and explains why packing extra pounds promotes cardiovascular disease, diabetes and several cancers.
So how could fat make weight loss easier?
For some time we have known that fat comes in different colors. The vast majority of body fat is white, hence WAT (white adipose tissue). Brown fat or BAT (brown adipose tissue) is a very different lump of lard. The brown hue is due to the high concentration of mitochondria, a cell's power facility. Mitochondria produce energy enabling cells to function. The mitochondria in BAT are different.
Here, the mitochondria are unharnessed from energy production and create heat. Hibernating animals and infants rely on this process to maintain body temperature. Think of a car in neutral with the gas pedal to the floor. You could burn through a tank of gas if you did it long enough. The gas represents our fat. If you increase BAT activity, you will burn off your fat stores. Decreasing fat lowers your risk for diabetes, cardiovascular disease, and certain cancers. The big bonus of course is you also loose that belly. It's all good.
It had been thought that as humans grow they loose all BAT. We now know this is not so. More importantly, we have discovered ways of activating whatever BAT remains from infancy and how to convert WAT to BAT. The brown fat cells that emerge in WAT under certain conditions are known as beige fat cells.
Four methods for the activation or creation of beige fat cells have been identified.
Cold exposure: Recent studies have demonstrated that people exposed to 15 to 16 degrees Celsius (59 to 60.8 degrees Fahrenheit) for six hours per day, for 10 days had a significant increase in BAT activity and volume.
This may seem extreme for the more cold-sensitive folks. We are still learning what might be the optimal cold exposure technique. If ice baths are your cup of tea, short dips may prove equally effective.
Chili Peppers: These spicy fruits from the genus Capsicum are members of the nightshade family. They contain high levels of capsinoids, a substance known to increase BAT activity. You don't have to set your GI tract on fire in order to harness the power of these peppers. Capsinoids are available as supplements and 9 mg per day for six weeks proved effective in increasing BAT activity and energy expenditure.
Exercise: In 2012 researchers discovered irisin, a hormone secreted by active muscle that promotes BAT activity. Many of the beneficial effects of exercise such as increased insulin sensitivity appear to be mediated by irisin. So exercise does more than use fat as an energy source. It transforms fat into a more metabolically active tissue that burns calories even when you are not exercising.
Melatonin: The pineal gland secretes this hormone in response to increasing darkness thereby signaling the body that it is time to sleep. Recent research found melatonin capable of amplifying the activating effects of exercise and cold exposure on BAT. This adds to the growing body of literature that links inadequate sleep with weight gain. The best way to maximize the melatonin effect is to get enough sleep. However the number of hours slept is not sufficient. Even seemingly insignificant light such as that emitted from gadgets like DVRs, computers, or cell phones can diminish melatonin levels. Interestingly, blue light (which seems like less of a disruptor of sleep) is the most powerful wavelength for inhibiting melatonin release.
This list shouldn't surprise us. Our genome has not changed significantly over the past 10,000 years while our sleep, diet, activity patterns and environments have been transformed. We are people of the 21st century, but our genetic programing remains essentially the same as Paleolithic people. This discordance explains the epidemic of metabolic diseases (cardiovascular diseases, Type 2 diabetes, metabolic syndrome, obesity and several cancers).
This list speaks to the price of sitting most of the time rather than moving most of the time, of inadequate sleep, light pollution and the loss of circadian rhythms that keep us in synchrony with the natural world, of a diet composed of a concoction of synthesized "food products" and lacking powerful fresh plants, and of over-controlled, over-heated thermal environments that eliminate the natural temperature swings of day and night and the seasons.
We find ourselves in the perverse position of having to reverse much of our "progress" in order to recreate some of the archaic conditions that characterized the environment in which we evolved. The fate of our health lies in an understanding of a past that stressed us in specific ways. We adapted to those challenges. That adaptation made us the remarkable creatures we are, still.