The human beings have variable demands of energy and therefore the supply is also equally variable. The absorbed metabolic fuel may be oxidized to CO2 and H2O or stored to meet the energy requirement as and when the body needs. In a well fed state the metabolism and organs integrate themselves to meet the energy demands and to metabolize or to store the consumed dietary components. The insulin becomes active to burn the carbohydrates as well as to store the excess. Well fed state makes hormone sensitive lipase inhibition through insulin to reduce the release of fatty acids. During starvation the metabolism gets reorganized to meet the energy demands. Starvation is a metabolic stress, which imposes certain metabolic compulsions on the organism. The glucagon activity increases to make an effort to build up the blood glucose level. The triacylglycerol of adipose tissue is the predominant energy reserve of the body. The hormone sensitive lipase becomes active to hydrolyze the triacyglycerol. The prolonged starvation results in the production of ketone bodies to provide the energy to brain.