White Fat vs. Brown Fat

White Fat vs. Brown Fat - How to “Dissipate” Fat for Heat to Lose Weight Faster

Before we get into it, please know mitochondria are the energy factories of your body that turn the food into ATP (the energy currency of our body).

White fat or white adipose tissue (WAT) is your body’s main type of fat and is found under the skin (subcutaneous fat) and around your internal organs (visceral fat). The major function of insulin is to store extra energy in the form of white fat. The white adipocytes (fat) have an enormous ability to store a large amount of energy with little or no wastage. This efficient capture and storage of energy appear to be an evolutionarily conserved developed phenomenon to cope with periods of food scarcity. [17] When it comes to obesity and type 2 diabetes, however, it makes sense to burn the white fat by “dissipating” it as heat. And that is when where brown fat plays a key role.

Brown fat or brown adipose tissue (BAT) is mainly found in hibernating animals (that sleep through the winter) and human babies to keep them warm. [18] BAT is located in the shoulder blades, surrounding the kidneys, the neck, and along the spinal cord, but also among WAT in the epicardial fat (around the heart) and the perivascular fat (surrounding certain blood vessels). The primary function of BAT is to dissipate energy in the form of heat (thermogenesis). [18]

The babies have brown fat deposits foremost primarily. The brown fat is by far more mitochondria- dense than white fat. That is why they are brown. The mitochondria in the brown fat act are uncoupled by a protein called uncoupled protein 1 (UCP1) which is located in the inner mitochondrial membrane. [19] That means, they not only burn the fat (or glucose) to make ATP-energy, but they also control thermogenesis by “wasting” the energy to produce heat. Because of that, babies don’t shiver in the cold water.

The uncoupled acting of mitochondria in the brown fat is inefficient but wonderfully effective to provide beneficial metabolic environments. The good news is that the white fat cells can behave like brown fat – “the browning of white fat”. The white fat is not converted into brown fat, but only can act like brown fat. In simple word terms, you can accelerate weight loss by making your white fat act like brown fat. How? Both through low-carb diet, cold exposure, [20] and Time Restricted Diet (intermittent fasting).

In a state of fasting, the white fats increase the number of mitochondria, which start to burn the fat for heat. A low-carb diet is associated with larger mitochondria and increased levels of UCP1 in white fat. [21] [22] Intermittent fasting stimulates beige brown fat development within white fat and dramatically ameliorates obesity, insulin resistance, and abnormal retention of fat in the liver (hepatic stenosis). [23] In simple words, through a low-carb diet combined with intermittent fasting, you accelerate the weight loss, increase insulin sensitivity, and reverse the fatty liver.

But why do white fat cells to waste energy and produce heat in a state of fasting? Maybe it has something to do with human evolution in cold times, when our ancestors, the hunter-gatherers, had to survive the severe cold with no food to eat until the next hunt.

The point is, through a low-carb diet combined with intermittent fasting, you enhance the fat burning significantly, by making the white fat behave like brown fat. Meaning, you are burning fat for producing heat. On the contrary Conversely, when brown fats are exposed to insulin, it's their metabolic rate slows down by half. , because it cannot act uncoupled in the presence of insulin. [24] Insulin binds itself to the receptors of brown fat cells and inhibits the uncoupled functioning of the mitochondria. Simply put, insulin doesn’t allow the mitochondria of brown fat cells to produce heat and hence "dissipating” energy. Insulin, as an anabolic hormone, doesn’t like to waste energy.

To keep the level of insulin down, you want to implement a low-carb diet and intermittent fasting into your lifestyle. In this way, you're accelerating you are accelerating your fat burning because your body not only burns it for fuel but also for generating heat. Cold shower and cold exposure also activate the brown fat behavior of white fat. The cold is a natural stimulator of brown fat and weight loss. [25]

Brown fat activation also lowers the blood sugar level and subsequently the demand for insulin. Brown fat takes in glucose and lipids from circulation, aiding in glucose clearance and relieving the demand for insulin secretion. [26] Fasting glucose concentrations in individuals with detectable brown fat are lower than in those without active brown fat. [27]

Summary

There are two kinds of fats:

• White fat is used to supply energy

• Brown fat is used to supply energy and heat

Intermittent fasting, combined with a low-carb diet and cold exposure accelerate dramatically the weight loss dramatically because it makes the white fat acts like brown fat. It means the white fat is burned away not only by supplying the body with energy, but also by being “wasted” by producing heat.

Scientific References

[17] Can Brown Fat Win the Battle against White Fat? Elattar S, Satyanarayana A. J Cell Physiol. 2015 Oct;230(10):2311-7. doi: 10.1002/jcp.24986. Review. PMID: 25760392. Waves of adipose tissue growth in the genetically obese Zucker fatty rat. MacKellar J, Cushman SW, Periwal V PLoS One. 2010 Jan 22; 5(1): e8197. Tracking adipogenesis during white adipose tissue development, expansion and regeneration. Wang QA, Tao C, Gupta RK, Scherer PE Nat Med. 2013 Oct; 19(10):1338-44.

[18] Brown adipose tissue: function and physiological significance. Cannon B, Nedergaard J. Physiol Rev. 2004 Jan; 84(1):277-359.

[19] Uncoupling protein--a useful energy dissipator. Klingenberg M. J Bioenerg Biomembr. 1999 Oct; 31(5):419-30. UCP1: its involvement and utility in obesity. Kozak LP, Anunciado-Koza R Int J Obes (Lond). 2008 Dec; 32 Suppl 7():S32-8.

[20] Mitochondrial uncoupling as a target in the treatment of obesity. Costford S, Gowing A, Harper MECurr Opin Clin Nutr Metab Care. 2007 Nov; 10(6):671-8. UCP1: its involvement and utility in obesity. Kozak LP, Anunciado-Koza R Int J Obes (Lond). 2008 Dec; 32 Suppl 7():S32-8.

[21] Srivastava S, Baxa U, Niu G, Chen X, Veech RL. IUBMB Life. 2013 Jan;65(1):58-66. doi: 10.1002/iub.1102. Epub 2012 Dec 10. Erratum in: IUBMB Life. 2014 Jul;66(7):519. PMID: 23233333

[22] Sahuri-Arisoylu M, Brody LP, Parkinson JR, Parkes H, Navaratnam N, Miller AD, Thomas EL, Frost G, Bell JD (2016) Reprogramming of hepatic fat accumulation and ‘browning’ of adipose tissue by the short-chain fatty acid acetate. Int J Obes 40(6):955–963.

[23] Li G, Xie C, Lu S, Nichols RG, Tian Y, Li L, Patel D, Ma Y, Brocker CN, Yan T, Krausz KW, Xiang R, Gavrilova O, Patterson AD, Gonzalez FJ. Cell Metab. 2017 Oct 3;26(4):672-685.e4. doi: 10.1016/j.cmet.2017.08.019. Epub 2017 Sep 14. Erratum in: Cell Metab. 2017 Nov 7; 26(5):801. PMID: 28918936.

[24] Insulin and the beta3-adrenoceptor differentially regulate uncoupling protein-1 expression. Klein J, Fasshauer M, Benito M, Kahn CR. Mol Endocrinol. 2000 Jun;14(6):764-73. PMID: 10847579.

[25] "USA-Fat”: prevalence is related to ambient outdoor temperature-evaluation with 18F-FDG PET/CT.Cohade C, Mourtzikos KA, Wahl RL J Nucl Med. 2003 Aug; 44(8):1267-70.

[26] Brown fat fuel use and regulation of energy homeostasis. Loyd C, Obici S. Curr Opin Clin Nutr Metab Care. 2014 Jul;17(4):368-72. doi: 10.1097/MCO.0000000000000063. Review. PMID: 24839950.

[27] A critical appraisal of the prevalence and metabolic significance of brown adipose tissue in adult humans. Lee P, Greenfield JR, Ho KK, Fulham MJ. Am J Physiol Endocrinol Metab. 2010 Oct;299(4):E601-6. doi: 10.1152/ajpendo.00298.2010. Epub 2010 Jul 6. PMID: 20606075