Dietary intake and resting energy expenditure in relation to weight loss in unselected cancer patients

Weight loss and anorexia are frequent findings in advanced cancer. The prog ressive wasting could be attributed to changes in dietary intake and/or ene rgy expenditure mediated by metabolic alterations. In this study, we analyz ed dietary intake in generalized malignant disease of solid tumor type in r elation to resting energy expenditure (REE) and reported weight loss. In a group of 297 unselected cancer patients from a university hospital outpatie nt clinic, dietary Intake of energy and macronutrients from a 4-day food re cord, REE by indirect calorimetry, height, weight and weight loss were reco rded, Protein intake was validated against 24 hr urine nitrogen in a subgro up (n = 53), and no indication of systematic misreporting was found. Mean d aily dietary intake was below maintenance requirements, 26 +/- 10 kcal/kg, Weight loss of more than 10% was present in 43% of patients and elevated RE E (> 110% of predicted) in 48%, Dietary intake did not differ between normo - and hypermetabolic patients, nor was tumour type or gender related to ene rgy and protein intake. Weight loss could not be accounted for by diminishe d dietary intake since energy intake in absolute amounts was not different and intake per kilogram body weight was higher in weight losing patients co mpared to weight-stable patients. Dietary macronutrient composition did not differ from the general population. Dietary intake of energy and protein w as decreased, but dietary macronutrient composition did not appear to be ch anged, Weight loss and hypermetabolism were frequent and not compensated fo r by an increase in spontaneous food intake. Our results indicate that an e xpected up-regulation of dietary intake in response to elevated energy expe nditure is frequently lost in cancer patients. This may be the explanation behind cancer cachexia rather than a primary decrease in appetite, (C) 2001 Wiley-Liss, Inc.