Fat is an essential ingredient of the diet of many animals. Fat is energy rich and consumption of fat is a good method to acquire energy. This energy is often stored as fat in fat cells in the body for lean times. Hibernating animals and animals that go through seasonal lean times often apply this strategy. Brown fat is a special kind of fat tissue that is specialized in producing heat. Mammalian babies often have brown fat to help them keep warm by producing heat. The storage of fat is not restricted to mammalians. Most animal groups can resort to this practice.
- See also: fat people