Energy is an important constraint to the organisms in natural conditions, being the energy acquired positively correlated with their fitness. When environmental changes occur systematically on time and within the range of normal conditions, the organisms are able to perceive the fluctuations and adequate their functions and behaviors to cope with them. However, the pollutant discharges induce organisms to display less suitable responses on the fitness context. Particularly, the energy allocation to different functional processes and behavior is deviated from levels that have been maximized under the usual environmental pressures. This work assesses the individual performance for acquisition, transformation, and use of energy in different processes as useful tools to predict biological damages. The effect induced by pollutants on searching, detecting, pursuing, handling, and capturing of food items able to modify the food acquisition is reviewed. Alterations on processes responsible for the assimilation of the energy ingested and its effect on energetic resources available to perform metabolic activities are considered. Each component of the energy budget balance, such as maintenance, external work, somatic growth, and reproductive investment are analyzed. The management here proposed is an approach to bridge the effect of pollutants on the energy budget components with the fitness to the environment.