(P11-044-25) Effects of an 8-Wk Daily Low Oxygen Exposure on Weight Loss, Body Composition and Metabolic Health: A Randomized, Double-Blind, Controlled-Feeding Trial Protocol

Objectives: Obesity is both a disease and a risk factor for other chronic diseases, such as cardiovascular disease, type 2 diabetes, and certain forms of cancers. While diet and exercise are the cornerstone of obesity prevention and treatment, a considerable number of individuals are non-responsive to existing weight loss interventions. Chronic exposure to low-oxygen conditions (e.g., high altitude) may enhance weight loss through a decrease in appetite and an increase in resting metabolic rate. Normobaric hypoxic exposure using in-home tent systems offers a novel and more accessible method of low-oxygen exposure but its ability to enhance weight loss in adults with obesity remains unknown. We assessed whether in-home, overnight, normobaric hypoxic exposure, promotes extra weight loss in adults with obesity.

Methods: Adults with obesity (n=50; BMI: 30-39.9 kg/m²) will be enrolled in this double-blind, parallel-arm, randomized-controlled clinical trial to evaluate changes in body weight and body composition following 8 weeks of prescribed caloric restriction (500 kcal/day below energy needs) 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. Energy intake and expenditure will be assessed using doubly labelled water, indirect calorimetry, accelerometery, and an ad libitum buffet meal. Modulators of energy intake and expenditure, including oxygen saturation, substrate oxidation, continuous blood glucose monitoring, insulin sensitivity, stool microbiome, iron absorption and indicators of iron status, thermic effect of glucose, subjective appetite and circulating appetite hormones, heart rate variability, urinary catecholamines, psychosocial factors, and sleep quality, will also be assessed.

Results: Twelve participants have been enrolled in the study. Of those participants, 11 have completed the intervention and 1 has dropped out of the study.

Conclusions: Chronic, overnight low oxygen exposure may provide a novel intervention to complement current weight-loss strategies, inform new strategies to accelerate weight loss, aid long-term weight management efforts, and benefit metabolic health in adults with obesity.

Funding Sources: National Institutes of Health (NIDDK)