Food preferences and weight change during low-fat and low-carbohydrate diets.

UNLABELLED: Understanding associations between food preferences and weight loss during various effective diets could inform efforts to personalize dietary recommendations and provide insight into weight loss mechanisms. We conducted a secondary analysis of data from a clinical trial in which participants were randomized to either a 'choice' arm, in which they were allowed to select between a low-fat diet (n = 44) or low-carbohydrate diet (n = 61), or to a 'no choice' arm, in which they were randomly assigned to a low-fat diet (n = 49) or low-carbohydrate diet (n = 53). All participants were provided 48 weeks of lifestyle counseling. Food preferences were measured at baseline and every 12 weeks thereafter with the Geiselman Food Preference Questionnaire. Participants were 73% male and 51% African American, with a mean age of 55. Baseline food preferences, including congruency of food preferences with diet, were not associated with weight outcomes. In the low-fat diet group, no associations were found between changes in food preferences and weight over time. In the low-carbohydrate diet group, increased preference for low-carbohydrate diet congruent foods from baseline to 12 weeks was associated with weight loss from 12 to 24 weeks. Additionally, weight loss from baseline to 12 weeks was associated with increased preference for low-carbohydrate diet congruent foods from 12 to 24 weeks. Results suggest that basing selection of low-carbohydrate diet or low-fat diet on food preferences is unlikely to influence weight loss. Congruency of food preferences and weight loss may influence each other early during a low-carbohydrate diet but not low-fat diet, possibly due to different features of these diets. CLINICAL TRIAL REGISTRY: NCT01152359.

Fluid management and goal-directed therapy as an adjunct to Enhanced Recovery After Surgery (ERAS)

© 2014, Canadian Anesthesiologists' Society.Optimal perioperative fluid management is an important component of Enhanced Recovery After Surgery (ERAS) pathways. Fluid management within ERAS should be viewed as a continuum through the preoperative, intraoperative, and postoperative phases. Each phase is important for improving patient outcomes, and suboptimal care in one phase can undermine best practice within the rest of the ERAS pathway. The goal of preoperative fluid management is for the patient to arrive in the operating room in a hydrated and euvolemic state. To achieve this, prolonged fasting is not recommended, and routine mechanical bowel preparation should be avoided. Patients should be encouraged to ingest a clear carbohydrate drink two to three hours before surgery. The goals of intraoperative fluid management are to maintain central euvolemia and to avoid excess salt and water. To achieve this, patients undergoing surgery within an enhanced recovery protocol should have an individualized fluid management plan. As part of this plan, excess crystalloid should be avoided in all patients. For low-risk patients undergoing low-risk surgery, a “zero-balance” approach might be sufficient. In addition, for most patients undergoing major surgery, individualized goal-directed fluid therapy (GDFT) is recommended. Ultimately, however, the additional benefit of GDFT should be determined based on surgical and patient risk factors. Postoperatively, once fluid intake is established, intravenous fluid administration can be discontinued and restarted only if clinically indicated. In the absence of other concerns, detrimental postoperative fluid overload is not justified and “permissive oliguria” could be tolerated.