Define Energy Requirements and Dietary Energy Recommendations?

Energy requirement, as you may recall studying earlier, is the amount of food energy needed to balance energy expenditure in order to maintain body size, body composition and a level of necessary and desirable physical activity consistent with long-term good health. This includes the energy needed [or the optimal growth and development of children, for the deposition of tissues during pregnancy, and for the secretion of milk during lactation consistent with the good health of mother and child. The recommended level of dietary energy intake for a population group is the mean energy requirement of the healthy, well-nourished individuals who constitute that group.

Energy requirements and recommended levels of intake are often referred to as daily requirements or recommended daily intakes. These terms are used as. a matter of convention and convenience, indicating that the requirement represents an average of energy needs over a certain number of days, and that the recommended energy intake is the amount of energy that should be ingested as a daily average over a certain period of time. There is no implication that this amount of energy must be consumed every day or that the requirement and the recommended intake remain constant day after day. A convenient time frame of one week has been often used in practice for defining the number of days over which the requirement and the recommended energy intake may be averaged, although there is no biological basis for this or any other time frame. Considering that habitual physical activities may vary on some days of the week a seven day period appears reasonable for averaging the requirement and the recommended intakes. Remember, estimates of energy requirements are derived from measurements of individuals. Measurements of a collection of individuals of the same gender and similar age, body size and physical activity are grouped together to give the average energy requirement - or recommended level of dietary intake - for a class of people or a population group.