There are reasons to question the dogma that nutritional support during the first week of critical illness is a priority. For example, metabolism and mitochondrial function are altered during critical illness (Fink 2001;Mizock 1984); calorie restriction has been beneficial in animal models of critical illness (Alexander 1989), and possibly in adults with critical illness (Ash 2005; Krishnan 2003); overfeeding is associatedwith adverse effects (Chwals 1994; Zaloga 1994); many trials in adults have given unclear evidence of benefit from early nutritional support in critical illness (Koretz 2007a; Koretz 2007; Koretz 2007b); and surrogate nutritional outcomes may not be adequate to confirm a benefit from nutritional support in terms of meaningful clinical outcomes (Heyland 1998b; Koretz 2005). Further, it has been found that in early critical illness children do not experience hypermetabolism (Framson 2007), and energy expenditure is close to or below calculated basal metabolic rate (Briassoulis 2000; Jacsik 2001; Martinez 2004; Oosterveld 2006; White 2000). Protein catabolism during this time cannot be averted by aggressive nutritional support, and anabolism with growth cannot be induced (Chwals 1994; Shew 1999).