Background Consensus definitions for disease‐associated malnutrition and sarcopenia include reduced skeletal muscle mass as a diagnostic criterion. There is a need to develop and validate techniques to assess skeletal muscle in clinical practice. Skeletal muscle mass can be precisely quantified from computed tomography (CT) images. This pilot study aimed to train registered dietitians (RDs) to complete precise skeletal muscle measurements using CT. Methods Purposive sampling identified RDs employed in clinical areas in which CT scans are routinely performed. CT training included (1) a 3‐Day training session focused on manual segmentation of skeletal muscle cross‐sectional areas (cm2, centimeter squared) from abdominal CT images at the third lumbar vertebra (L3), using sliceOmatic® software, and (2) a precision assessment to quantify the intraobserver and interobserver precision error of repeated skeletal muscle measurements (30 images in duplicate). Precision error is reported as the root mean standard deviation (cm2) and percent coefficient of variation (%CV), our primary performance indicator, was defined as a precision error of <2%. Results Five RDs completed CT training. RDs were from three clinical areas: cancer care (N = 1), surgery (N = 2), and critical care (N = 1). RDs' precision error was low and below the minimal acceptable error of <2%; intraobserver error was ≤1.8 cm2 (range, 0.8–1.8 cm2) or ≤1.5% (range, 0.8%–1.5%) and interobserver error was 1.2 cm2 or 1.1%. Conclusion RDs can be trained to perform precise CT skeletal muscle measurements. Increasing capacity to assess skeletal muscle is a first step toward developing this technique for use in clinical practice.

In January 2022 a group of experts came together to discuss current perspectives and future directions in nutritional immunology as part of a symposium organized by the Canadian Nutrition Society. Objectives included (1) creating an understanding of the complex interplay between diet and the immune system from infants through to older adults; (2) illustrating the role of micronutrients that are vital to the immune system; (3) learning about current research comparing the impact of various dietary patterns and novel approaches to reduce inflammation, autoimmune conditions, allergies, and infections; and (4) discussing select dietary recommendations aimed at improving disease specific immune function. The aims of this review are to summarize the symposium and to identify key areas of research that require additional exploration to better understand the dynamic relationship between nutrition and immune function.