By Sue Kosharek
lifestyle@postbulletin.com
Q: What is brown fat?
A: Our bodies are made up of two types of fat, or adipose tissue, We have white adipose and brown adipose tissue. White fat stores energy, provides insulation and cushioning of vital organs (like the heart, kidneys, liver). When we think of body fat, we are usually thinking of white adipose tissue. When we lose weight, we are trying to decrease the white fat cells.
Brown fat is present in high quantities in newborns. It makes up about five percent of their body weight. The brown fat actually produces heat. It does this by breaking down fat molecules into fatty acids; when this happens energy is released as heat. As infants eat more and begin to develop layers of white fat, the brown fat begins to disappear. Hibernating animals have brown fat and use this process to get through the winter.
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Because brown fat actually burns up calories, many "diets" have been touted to increase brown fat. Unfortunately for most of us, this brown fat diminishes with age and is virtually gone by adulthood.
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