Brown fat (brown adipose tissue) is a type of body fat that regulates your body temperature in cold conditions. Brown fat activates right before you start to shiver. Brown fat also burns calories and stores energy. You have a small percentage of brown fat in your body compared to white fat.
Brown fat, also called brown adipose tissue, is a type of body fat that keeps you warm when you get cold. Brown fat also stores energy and helps your body burn calories. Brown fat starts working (activates) in cold temperatures.
There are different types of fat in your body. Healthcare providers identify each type of fat by its color and function, including:
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Brown fat is responsible for producing heat to warm the blood in your body. You’ll notice brown fat burning right before you start to shiver because the fat activates (turns on) in cold temperatures. It produces heat by breaking down blood sugar (glucose) and molecules of fat. This process (thermogenesis) creates heat to help you maintain your body temperature.
Brown fat helps your body in different ways including:
Tiny molecules make up brown fat and those molecules are fat cells. Molecules consist of fatty acids and glycerol. The anatomy of brown fat resembles muscle more than it resembles other fat in your body because the cells that store brown fat in tissues (adipocyte) are smaller.
When fat collects within your body, fat molecules lump together to create a mass. Brown fat looks like a small, brown, lumpy oval.
Fat in your body has different colors that designate its function. Brown fat is brown because the fat cells are full of mitochondria. Mitochondria is made up of a lot of iron, which gives brown fat its color.
Brown fat in newborns is located in their back, neck and shoulders. During childhood and adolescence, brown fat scatters around the body. Brown fat in adults is located around the neck, kidneys, adrenal glands, heart (aorta) and chest (mediastinum).
The amount of fat in your body varies from person to person. You have less brown fat than white fat in your body.
In newborns, brown fat makes up 2% to 5% of their total body weight. During childhood and adolescence, the amount of brown fat reduces. As an adult, you have a small amount of brown fat. People who are lean, like athletes, have more brown fat in their bodies than others.
Several conditions affect brown fat in your body, including:
Your provider will offer tests to check the health of the fat cells in your body through a couple of tests, including:
You get fat from the foods you eat. Fat is essential because it produces energy. There are a lot of different foods that provide good sources of fat, including:
Always combine foods that have good fat with vegetables, whole grains, protein and dairy to eat a well-balanced diet.
Foods you should avoid to prevent unhealthy fat from collecting in your body include:
People might want to increase the amount of brown fat in their bodies if they want to lose weight and burn calories. You can take steps to increase the amount of brown fat in your body by:
A note from Cleveland Clinic
Brown fat positively influences the way your body works by maintaining your body temperature in cold conditions and producing energy. Take steps to keep the brown fat in your body healthy by eating a well-balanced diet, exercising and lowering the temperature in controlled environments by taking a cold shower or an ice bath a couple of times a week. If you’re unsure what foods or activities are right for your body, talk with a healthcare provider.
Last reviewed by a Cleveland Clinic medical professional on 08/07/2022.
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