The cells in the human body derive the energy required for various bio-chemical processes by using energy rich sources like carbohydrates and fats. Fat molecules stored in human body acts as long term energy reserves. Fat is stored as triglycerides in the adipose tissues present beneath the human skin. About 9 calories of energy is stored in each gram of fat. These fats stored in the cells can be broken down to provide the energy required for cell metabolism. So, we can say the fat storage is an evolutionary adaptation in human beings to survive conditions of food shortage like famine.
