Impact of Well-Timed vs. Mis-timed Sleep Extension on Adolescents’ Dietary Intake

项目摘要 最近的研究表明，睡眠可以在预防肥胖和长期发病率方面发挥新的作用。 人口研究和实验研究发现睡眠太少预示着肥胖的发展 研究表明，睡眠时间短会增加饮食摄入量，而不会增加体力活动。睡眠可能是一种 针对青少年的特别有力的干预目标。在青春期，睡眠不足是非常严重的 常见的是，肥胖率上升最多，非睡眠导向的肥胖预防计划上升最少 成功，年轻人可以养成持久的饮食模式，为终身肥胖和 健康风险。我们的实验室既展示了让青少年睡得更久的承诺，也展示了一项重要的知识 差距。我们发现，通过较早的就寝时间延长青少年的睡眠时间可以显著减少卡路里的摄入量 早起时型(“晨光百灵鸟”；喜欢早睡早起的人)，而不是晚睡时型(“夜” 猫头鹰“；喜欢晚睡和起床的人)。这一效应不仅在统计上很强，而且在大约400 每天卡路里的不同，随着时间的推移，可能会导致体重的重大变化。除了卡路里以外， 在延长睡眠时间后，百灵鸟和猫头鹰消耗的血糖负荷也有类似的差异， 血糖负荷已经独立地与长期发病率有关。我们断言，其中的差异 百灵鸟和猫头鹰对长时间睡眠的反应是由于昼夜节律失调：两者之间的不匹配 外部睡眠-唤醒需求和内部生物钟的计时。我们建议，对于青少年猫头鹰， 早睡干预会导致睡眠时间错位，抵消了长时间睡眠的好处 持续时间。在成年人中，严重的昼夜节律失调会显著增加肥胖的风险，甚至 轻度失调与较高的卡路里摄入量有关。如果因果关系在青春期成立， 强调提早就寝的常见睡眠建议可能会浪费有限的资源，甚至对 猫头鹰。相比之下，一种考虑时型的方法可能会利用改进的 我们为云雀展示的睡眠。在这里，我们提出了一个新的实验研究，在这个研究中，124名健康的14- 18岁的受试者(62只猫头鹰和62只百灵鸟)完成一项为期3周的试验，包括睡眠限制和睡眠。 延期，其中延期期间被随机分配为对齐，而不是相对于 时刻表。我们将独立关注卡路里摄入量和血糖负荷，评估饮食效果。 相对于青少年的内部生物钟，当睡眠时间适时与不适时相比，睡眠延长的可能性更大。我们会 测试一个因果模型，在该模型中，睡眠时间在促进或否定睡眠的益处方面起着重要作用 延长睡眠时间。这是我们的研究计划的关键下一步，该计划已经显示出睡眠的前景 延长以防止肥胖和发病，但到目前为止只适用于早期时型(LARK)。在这个结束的时候 研究表明，我们预计会有更好地利用睡眠的力量来预防肥胖所需的知识 和高危青少年的长期发病率，为更有效的公共卫生干预奠定了基础。

Project Summary Recent research shows that sleep could play a novel role in preventing obesity and long-term morbidity. Population studies find that too little sleep predicts the development of obesity and experimental studies show that short sleep increases dietary intake without increasing physical activity. Sleep may be a particularly potent intervention target for adolescents. During adolescence, inadequate sleep is very common, obesity rates are rising most, non-sleep-oriented obesity prevention programs have had least success, and young people can develop enduring dietary patterns that set the stage for life-long obesity and health risk. Our lab has shown both the promise of longer sleep for adolescents and a critical knowledge gap. We found that extending adolescents’ sleep via earlier bedtimes impressively reduced caloric intake for early chronotypes (“Morning Larks”; who prefer early bed- and rise times), but not late chronotypes (“Night Owls”; who prefer late bed- and rise times). The effect was not only statistically strong, but at roughly 400 calories difference per day, could add up to major shifts in body weight over time. Beyond calorie counts, there was a similar discrepancy in the glycemic load consumed by Larks and Owls after sleep extension, and glycemic load has been independently linked to long-term morbidity. We assert that the discrepancy in how Larks and Owls responded to longer sleep is due to circadian misalignment: a mismatch between the timing of external sleep-wake demands and internal biological clock. We propose that, for adolescent Owls, an early-to-bed intervention induces misaligned sleep timing that counters the benefits of longer sleep duration. In adults, severe circadian misalignment dramatically increases the risk for obesity, and even modest misalignment is linked to higher caloric intake. If a cause-effect relationship holds in adolescence, common sleep advice emphasizing earlier bedtimes might waste limited resources or even do harm for Owls. In contrast, an approach that considers chronotype might capitalize on the potent effect of improved sleep that we have shown for Larks. Here, we propose a novel experimental study in which 124 healthy 14- 18-year-olds (62 Owls and 62 Larks) complete a 3-week trial involving periods of sleep restriction and sleep extension, in which the extension periods are randomly assigned to be aligned vs. misaligned relative to chronotype. Focusing independently on caloric intake and glycemic load, we will assess the dietary effect of sleep extension when it is well-timed versus poorly-timed relative to adolescents’ internal clocks. We will test a causal model in which sleep timing plays an important role in promoting or negating the benefits of sleep extension. This is pivotal next step for our research program, which has shown the promise of sleep extension to prevent obesity and morbidity, but so far only for early chronotypes (Larks). At the end of this study, we anticipate having the knowledge needed to better harness the power of sleep to prevent obesity and long-term morbidity for at-risk youth, laying the foundation for more effective public health interventions.