energyadjusted

Energy-adjusted refers to statistical methods that control for total energy intake or energy expenditure when analyzing dietary data or energy-related measurements. In nutrition research, adjusting for energy aims to separate the effects of what people eat from how much they eat overall, enabling fairer comparisons across individuals and populations with different energy intakes.

Common methods include the residual method, in which a nutrient or metabolite is regressed on total energy and the residuals (often plus a constant) are used as the energy-adjusted values. Another approach is the nutrient-density method, expressing intake per unit of energy (for example, grams per 1000 kcal). Both methods seek to reduce confounding by total energy intake and to facilitate interpretation across studies with varying energy consumption.

The primary purpose of energy adjustment is to highlight differences in diet composition rather than sheer caloric intake. It helps researchers evaluate whether associations with health outcomes reflect nutrient balance or dietary patterns, improves cross-study comparability, and mitigates measurement error related to energy reporting.

Applications span nutrition epidemiology, clinical nutrition, and public health surveillance. Researchers use energy-adjusted measures when studying obesity, cardiovascular disease, diabetes, cancer risk, and diet quality, as well as in analyses of dietary patterns and nutrient density.

Limitations include dependence on the chosen adjustment method, potential loss of intuitive interpretability, and the possibility that energy adjustment removes biologically meaningful signals if total energy intake is itself causally related to the outcome. Careful method selection and transparent reporting are advised.