Adjusted Body Weight, Con: Why Adjust Body Weight in Energy‐Expenditure Calculations?

Abstract

Evaluation of energy requirements of normal individuals and hospitalized patients is most often accomplished using an energy equation. Energy equations attempt to measure resting metabolic rate (RMR), the largest factor in total daily energy expenditure. Components of most energy equations include height, weight, age, and gender. These factors are related to energy expenditure; however, each factor has individual characteristics that affect energy expenditure. Body weight is a major factor in RMR and total daily energy expenditure. For obese individuals, estimation of energy expenditure may be a challenge due to the increased body weight. Therefore, some equations attempt to minimize the effect of body weight on energy expenditure assessment by adjusting the obese individual's body weight. Data do not support adjustment of body weight in normal individuals. In hospitalized patients, there are several equations that are used to estimate energy expenditure of obese patients, which include adjusting the body weight and modifying the overall energy requirements. Measurement of RMR can obviate the need for estimating energy expenditure. It is important to evaluate any energy-expenditure equation that is used to estimate energy needs in normal people and hospitalized patients before applying it to patient care.