Brown Fat and Why It Matters
March 12, 2025At this point, most people know that there are different types of fat. In this blog, we will look at the role of brown fat. The two most common types of fat are white and brown. You may be familiar with subcutaneous and visceral fat, both of which are considered white fat. Brown fat plays a completely different role and can actually help with weight loss. However, taking full advantage of this type of fat is very difficult, and we are just beginning to better understand it. Most scales can tell your percent body fat, and some give you a breakdown of subcutaneous and visceral fat. The only way to measure brown fat is using a special radiological test that uses PET/CT technology.
White Fat and it's Role
White fat plays a role in energy storage. Subcutaneous fat is found under the skin, typically in the hips, arms, and legs. This type of fat can be easily seen and make people very self-conscious, but it doesn’t necessarily cause significant metabolic disease. Subcutaneous fat contributes to joint-related problems since the joints have to carry a large amount of weight, putting extra load on the joints. Over time, the joints begin to break down, and people develop osteoarthritis. Additionally, it can cause skin breakdown due to chafing of thighs, breasts, and other areas.
Visceral fat is usually found in the abdominal cavity, including the fatty apron known as the greater omentum, and it can surround or infiltrate organs such as the liver, kidneys, and heart. Visceral fat is dangerous because it causes inflammation throughout the body. Too much visceral fat has been associated with an increased risk of developing metabolic syndrome, diabetes, cardiovascular disease, and elevated blood pressure. Brown fat is much less known because it is rarely mentioned. Research shows that it plays a role in the regulation of body temperature, whole-body energy expenditure, and body fatness (1).
Brown Fat and it's Role
When a baby is developing, there is a relatively large amount of brown fat located around the clavicles, the scapula, and around the spine. As kids grow up to be adults, it becomes greatly diminished. The greater the amount, the greater the metabolic rate. It is difficult to increase brown fat. There is active research to better understand brown fat and how to harness its benefits. There is research on medications that can increase or activate a larger amount of brown fat. Mirabegron is being investigated as a possible medication that can activate it. Interestingly, another very useful method for increasing the activity of brown fat is exposure to cold. You have to be careful not to get frostbite; that is not the goal.
Cold has been found to be one of the strongest stimulants of brown fat. In a study with men who had undetectable or low brown fat activity and were kept in a cold environment for 2–6 hours every day for several weeks, their brown fat activity was significantly increased while body fat was decreased.
In conclusion, there are multiple types of fat, some useful and some dangerous. We all need a certain amount of fat for survival and normal bodily function. We are just beginning to have a better understanding of brown fat. One day, there may be a pharmacological approach to help people with very low levels or activity of brown fat. Perhaps cold exposure will play a greater role in the treatment of obesity.
References
(1) Combating Obesity With Thermogenic Fat: Current Challenges and Advancements. Ruping Pan, et al. Front. Endocrinol., 14 April 2020. Sec. Obesity Volume 11 - 2020 | https://doi.org/10.3389/fendo.2020.00185.
This article is meant for informational purposes. Please discuss this with your healthcare provider for your safety.
Dr. Leon Katz MD, FACS, FASMBS, is a bariatrician specializing in non-surgical, medically supervised weight loss at Dr. Leon Katz Medical Weight Loss Center.
 | ABOUT THE AUTHOR Dr. Leon Katz MD, FACS, FASMBS, is a bariatrician specializing in non-surgical, medically supervised weight loss. He focuses on patients seeking alternatives to surgery and those needing care after bariatric procedures. Dr. Katz was recently the director of a major medical weight loss program. With extensive experience in establishing successful weight management programs, he now concentrates exclusively on non-surgical weight loss solutions. Dr. Katz is a Diplomate of the American Board of Obesity Medicine and Fellow of American College of Surgeons. Dr. Katz currently practices at Dr. Leon Katz Medical Weight Loss Center. |
