Effects of daily low oxygen exposure on weight status, body composition, and metabolic health

项目摘要/摘要 肥胖及其相关的代谢状况是一个重大的公共健康负担，导致 美国每年约1500亿美元。肥胖既是一种疾病，影响着三分之一的美国人，也是一个危险因素 对于其他慢性疾病，如心血管疾病、2型糖尿病和13种形式的 癌症。饮食和锻炼是预防和治疗肥胖的基石。然而，a 相当多的人对现有的减肥干预措施没有反应， 肥胖率继续上升。因此，需要非常规方法来补充 目前的减肥策略。每天暴露在低氧环境中可能有助于增加目前的体重-- 损失策略。中等海拔(1,500-3,500米)和较高海拔(≥3,500米)环境 由于较低的大气压力(作为参考，丹佛的CO为~1600米)，自然缺氧 和Mt.俄勒冈州的胡德海拔约3500米)。研究表明，海平面上的原住民暴露在中等- 或连续5天或更长时间的高原减肥，这是延长的结果 血液和组织氧合减少，导致能量消耗增加和 食欲下降。然而，实施低氧作为减肥的一种手段 到目前为止，由于旅行到偏远地区或进入海拔高度的后勤限制，限制了 密室。一种安全、成本更低、在后勤上更可行的替代方案是使用 商业上可用的、海平面上的低氧系统，它产生了常压低氧 环境。无论是在家中、过夜、常压低氧暴露，与 常压常氧暴露，促进肥胖成年人体重下降 未知。此外，能量平衡的决定因素，包括能量摄入和消耗， 而它们对常压低氧诱导的体重减轻的相对贡献还没有 调查过了。拟议的双盲、平行对照、随机临床试验的目标是 评估体重和成分的变化，评估能量平衡的决定因素 (摄入和消耗)，并测量能量平衡的调节器，遵循8wk卡路里 限制(-500kcal/d)与通宵暴露于常压低氧(8 小时/夜，15%FiO2，~2640m)或常氧(8h/夜，21%FiO2)，使用商业上可用的， 居家帐篷系统，适用于肥胖成年人。慢性(8周)，通宵(8小时/晚)低 氧气暴露可能会提供一种非常规的方法来补充目前的减肥效果 战略，提供加速减肥的新战略，帮助长期体重管理 努力，并有益于肥胖者的代谢健康。

Project Summary/Abstract Obesity and associated metabolic conditions are a significant public health burden, costing the U.S. ~$150 billion annually. Obesity is both a disease, affecting 1 in 3 Americans, and a risk factor for other chronic diseases, such as cardiovascular disease, type 2 diabetes, and 13 forms of cancers. Diet and exercise are the cornerstone of obesity prevention and treatment. However, a considerable number of individuals are non-responsive to existing weight-loss interventions and obesity rates continue to rise. Therefore, non-conventional approaches are needed to supplement current weight-loss strategies. Daily exposure to low-oxygen conditions may aid in current weight- loss strategies. Moderate (1500-3500 m) and higher (≥ 3500 m) altitude environments are naturally hypoxic due to the lower atmospheric pressure (for reference, Denver, CO is ~1600 m and Mt. Hood in Oregon is ~3500 m). Studies show that sea-level natives exposed to moderate- or high- altitude continuously for 5 or more days lose weight, which is a consequence of prolonged reductions in blood and tissue oxygenation that lead to increased energy expenditure and decreased appetite. However, implementation of hypoxia as a means for weight loss has been limited, to date, by the logistical constraints of traveling to remote locations or access to an altitude chamber. A safe, less expensive, and more logistically feasible alternative is the use of commercially available, low-oxygen systems at sea level, which create a normobaric hypoxic environment. Whether in-home, overnight, normobaric hypoxic exposure, compared to normobaric normoxic exposure, promotes body mass loss in adults with obesity remains unknown. Furthermore, determinants of energy balance, including energy intake and expenditure, and their relative contribution to normobaric hypoxia-induced weight loss have not been investigated. The objective of the proposed double-blind, parallel-arm, randomized clinical trial is to evaluate changes in body weight and composition, assess determinants of energy balance (intake and expenditure), and measure modulators of energy balance, following 8 wk of calorie restriction (-500 kcal/d) in combination with either overnight exposure to normobaric hypoxia (8 h/night, 15% FiO2, ~2640 m) or normoxia (8 h/night, 21% FiO2), using a commercially available, in-home tent system, in adults with obesity. Chronic (8 weeks), overnight (8 hours/night) low oxygen exposure may provide a non-conventional approach to supplement current weight-loss strategies, inform new strategies to accelerate weight loss, aid long-term weight management efforts, and benefit metabolic health in individuals with obesity.