Brown adipose tissue is a form of fat that is stored in adipose tissue which is made up of cells called adipocytes. This tissue is found under the skin and in the intra-abdominal region. Brown adipose tissue also known as brown fat produces heat, beige adipose tissue, is located in the white adipose tissue and its adipocytes resemble brown adipocytes. It exists in several forms.
Whereas white adipose tissue, which is the body’s main fat reserve and accounts for approximately 20% of an adult’s weight, it is the main fat composition commonly found in the body of an adult, but there exists an important second type of adipose tissue known as brown adipose tissue, in this article, we are going to review in detail what is known as brown adipose tissue, its functions, and importance.
Brown Adipose Tissue: An Adaption To The Cold
Brown adipose tissue is present in some mammals, especially those that hibernate. It represents an adaptation of the body to cold temperatures since it is used to quickly produce heat. In the case of humans, brown fat is particularly abundant in the fetus and newborn, in whom brown adipose tissue accounts for approximately 5% of birth weight. Baby brown fat is located around large vessels, in the neck, around the heart, kidneys, and adrenals. Although brown fat decreases as an individual grows, adults always retain some of it too. It is then rather near the adrenals, the clavicles, and the spine.
This particular fat is made up of brown adipocytes. In humans, it is mainly present in the fetus and newborn, brown adipose tissue is made up of cells that burn glucose by producing heat, this type of fat as said earlier is very present in babies and helps protect them from cold.
Brown fat gradually disappears in adulthood ( it is then called beige adipose tissue) to be replaced by white adipose tissue which tends to store fat. Though studies have shown that brown adipose tissue may be present in some adults as a result of constant exposure to cold which thereby helps in the activation of this brown fat for protective mechanism and for other functional medical importance for regulating glucose metabolism in general and diabetes in particular. Numerous scientific articles have highlighted the role of cold in the activation of brown adipose tissues.
How Does Brown Adipose Tissue Produce Heat?
In brown adipose tissue, heat is possible due to a mitochondrial protein called thermogenin, or UCP1 ( UnCoupling Protein 1). An uncoupling protein: it dissipates the energy of lipid oxidation in the form of heat, instead of being coupled to the phosphorylation of ADP into ATP. In the mitochondria of brown adipocytes, the energy released by the oxidation of fatty acids is used solely for heat production. To achieve this, brown adipocytes need a lot of oxygen, supplied by blood circulation.
Some Important Functions Of Brown Adipose Tissue
🔹 The Impact Of Brown Fat On Health
In addition to weight, brown fat could influence obesity-related disorders, such as type 2 diabetes or fatty liver disease. As white adipocytes can turn brown, adipocyte browning appears to improve metabolic health.
🔹 Brown Fat And Obesity
Our weight depends on the balance between the energy we absorb through food and what we expend for our physical activities and our basic metabolism. The basic metabolism corresponds to the obligatory functions of the body, such as digestion, respiration, heartbeat, but also thermoregulation. In adults, brown adipose tissue activity is reduced in obesity. This is while we can imagine that the reactivation of brown fat could provide metabolic benefits.
Importance Of Brown Adipose Tissue In The Body
It is generally believed that brown fat helps burn more energy in the cold, which usually results in better regulation of sugar metabolism and better insulin sensitivity. Brown adipose tissue could play a role in the fight against diabetes in humans. Other importance of brown adipose tissue are:
- It maintains the body temperature
- Produces and stores energy
- Burns calories
- Helps control blood sugar and insulin levels
Maintaining constant body temperature is an important factor that determines most physiological functions in humans, and thus the major component function of brown adipose tissue, it is therefore pertinent for an individual to take sensitive measures to keep brown fat in the body healthy through regular exercise and eating balanced diets.