Department of Psychology, Brescia University College, London, Ontario N6G 1H2, Canada; Department of Psychology, Western University, London, Ontario N6A 5C2, Canada.
Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
Appetite. 2017 Nov 1;118:49-59. doi: 10.1016/j.appet.2017.07.016. Epub 2017 Jul 15.
Hyperpalatable foods are highly pleasurable and possess a heightened capacity to stimulate eating. Adolescents appear especially vulnerable to hyperpalatable foods. These foods are typically high in sugar, fat, or both, but the specific elements that underlie their increased consumption are still not clearly understood. Combinations of high fat and high sugar may particularly intensify overeating. Animal models allow investigation of the consumption of these foods separately from many of the environmental and psychological influences that impact eating in humans. The current study compared intakes of sucrose, fat, and a sucrose-fat combination when offered to male and female rats intermittently (2 h, three times per week for five weeks) during the vulnerable period of adolescence. Consumption of these foods, and of freely available normally nutritive lab chow was measured. Animals given the sucrose-fat food consumed significantly more than all other groups and were the only group to show significant increases in consumption during the first week. Moreover, the sucrose-fat group consumed significantly less chow than any other group. In comparison with previous reports in adult rats, adolescent rats appeared to heighten consumption of the sucrose-fat food more markedly and to show less pronounced sex differences. These data highlight the unique vulnerability and increased biological susceptibility of adolescent rats to sweet-fat food rewards and demonstrate the need to similarly investigate the preference for and the consumption of different hyperpalatable foods in human adolescents.
高能量食物非常美味,具有强烈的刺激进食的能力。青少年似乎特别容易受到高能量食物的影响。这些食物通常富含糖和脂肪,或者两者都有,但它们增加摄入的具体因素仍不清楚。高脂肪和高糖的组合可能会特别加剧暴饮暴食。动物模型允许在人类饮食受到许多环境和心理影响的情况下,分别研究这些食物的摄入情况。本研究比较了雄性和雌性大鼠在青春期易受影响期间间歇性(2 小时,每周三次,持续五周)摄入蔗糖、脂肪和蔗糖-脂肪混合物的情况。测量了这些食物以及自由获取的正常营养实验室饲料的摄入量。摄入蔗糖-脂肪食物的动物比其他所有组都消耗更多,并且是唯一一组在第一周消耗明显增加的组。此外,蔗糖-脂肪组消耗的实验室饲料比任何其他组都少。与成年大鼠的先前报告相比,青春期大鼠似乎更明显地增加了对蔗糖-脂肪食物的消耗,并且性别差异不那么明显。这些数据突出了青少年对甜-脂肪食物奖励的独特脆弱性和更高的生物学易感性,并表明需要类似地研究人类青少年对不同高能量食物的偏好和消耗。