Pre-Ingestive Influences on Solid and Fluid Food Intake in Lean and Obease Adults

描述（由申请人提供）：最近超重和肥胖患病率的显著增加暗示了这些问题的病因中的行为因素，因此，建议干预策略。目前的建议假设，这一趋势在一定程度上可归因于能量饮料消费量的增加，因为它们的消费量与BMI趋势一致上升，将它们纳入或排除在饮食中会导致可预测的体重变化，它们现在为人口提供了超过20%的每日能量，它们引起的食欲和饮食反应比半固体或固体食物更弱。提出了四项人体研究，以对比一系列食欲和生理反应，以选择进食前（例如，认知、口腔感觉、咀嚼）对摄入液体和固体食物形式的影响。早期的研究表明，食物的预期能量含量比食物的实际能量含量更能预测它们对食欲的影响，而流变特性会影响这种预期。研究1将通过控制摄入前后食物的预期和实际流变特性，探索摄入相匹配的液体和固体食物的预期饱腹感、胃肠道转运时间、肠道激素分泌和血糖反应。据报道，大量营养素对食欲的影响是有层次的，但在液体中似乎不太可预测。研究2将监测对营养成分不同的液体和固体食物的食欲反应，以澄清这一问题。由于假设咀嚼对食欲、胃肠道转运、肠道激素分泌和血糖反应的独立和协同作用，这些结果将在控制咀嚼活动并结合饮酒后进行测量。研究4将通过液体和固体饮食刺激研究头期反应对餐后葡萄糖、胰岛素和选定肠道肽浓度的作用。此外，学习在这些反应中的作用将被测试。越来越多的证据表明，在摄食的调节中，奖励系统可能超越了体内平衡的食欲线索。所有的试验都将对比瘦人和肥胖者的研究结果，以确定能量平衡的调节机制是否可能不那么精确，尤其是对饮料而言，后者组。研究结果应该有助于制定饮食建议和产品，以解决超重/肥胖问题。公共健康相关性：饮料占每日能量摄入的20%以上。因为它们的饱腹感值低，只引起较弱的代偿性饮食反应，它们与体重增加和肥胖有关。对饮料和其他食物形式对能量平衡影响的不同机制的进一步了解，有必要支持或挑战将饮料摄入与肥胖联系起来的行为数据，并制定有效的体重管理干预策略。该项目将探索与饮料和固体食物摄入相关的摄入前因素（如认知、口腔感官提示、咀嚼）是否会在瘦肉和肥胖个体中引起涉及能量平衡的食欲、饮食和生理反应（如胃肠道转运、肠道内分泌分泌、血糖）的差异。

DESCRIPTION (provided by applicant): The marked recent increase in overweight and obesity prevalence implicates behavioral factors in the etiology of these problems and, as a consequence, suggests strategies for intervention. The present proposal hypothesizes the trend is attributable, in part, to increasing consumption of energy-yielding beverages since their consumption has risen in concert with BMI trends, their inclusion or exclusion from diets leads to predictable weight changes, they now contribute over 20% of daily energy in the population and they elicit weaker appetitive and dietary responses than semi-solid or solid foods. Four human studies are proposed to contrast an array of appetitive and physiological responses to selected pre-ingestive (e.g., cognitive, orosensory, masticatory) influences on ingestion of fluid and solid food forms. Early work indicated the expected energy content of foods better predicted their impact on appetite than their true energy content and rheological properties influence this expectation. Study 1 will explore the anticipated satiety effects, GI transit time, gut hormone secretion and glycemic response to ingestion of matched fluid and solid food forms by manipulating the expected and actual rheological properties of the foods prior to and following ingestion. A heirarchy of appetitive effects have been reported for the macronutrients, but appear less predictable in fluids. Study 2 will monitor appetitive responses to fluid and solid foods varying in nutrient content to clarify this issue. Because of hypothesized independent and synergistic effects of mastication on appetite, GI transit, gut hormone secretion and glycemic responses, these outcomes will be measured following controlled masticatory activity in conjunction with drinking. Study 4 will examine the role of cephalic phase responses on post-prandial glucose, insulin and selected gut peptide concentrations using fluid and solid dietary stimuli. In addition, the role of learning in these responses will be tested. Increasing evidence suggests that the reward system may override homeostatic appetitive cues in the regulation of feeding. All trials will contrast findings from lean and obese individuals to determine whether the regulatory mechanisms for energy balance may be less precise, especially for beverages, in the latter group. The findings should aid development of dietary recommendations and products to address the problems of overweight/obesity. PUBLIC HEALTH RELEVANCE: Beverages contribute over 20% of daily energy intake. Because they have low satiety value and elicit only weak compensatory dietary responses, they have been implicated in weight gain and obesity. An improved understanding of the mechanisms by which beverages and other food forms differ in their impact on energy balance is warranted to support or challenge the behavioral data linking beverage intake to obesity and to develop effective intervention strategies for weight management. This project will explore whether pre-ingestive factors (e.g., cognition, orosensory cues, mastication) associated with beverage versus solid food ingestion differentially elicit appetitive, dietary and physiological (e.g., GI transit, gut endocrine secretion, glycemia) responses involved in energy balance in lean and obese individuals.