Fasting therapy improves nocturnal hypoxemia and metabolic parameters in overweight/obese adults with sleep-related...

Sleep-related breathing disorder (SRBD) is a prevalent condition closely linked to obesity, yet effective and well-tolerated treatment options beyond CPAP are limited. Fasting therapy induces rapid weight loss and metabolic improvement, but its effects on SRBD remain unexplored. This pilot study aimed to evaluate the impact of fasting therapy on nocturnal hypoxemia and cardiometabolic health in adults at risk for SRBD.

In this open-label, single-arm pilot study, 57 adults with overweight/obesity, nocturnal hypoxemia, and symptoms of SRBD underwent a 7-day medically supervised fasting protocol. Nocturnal oxygenation, body composition, blood pressure, and metabolic parameters were assessed. Bonferroni correction was applied to the four primary oxygenation outcomes (adjusted α = 0.0125).

After fasting therapy, average SpO₂ increased from 94.8 ± 2.0% to 95.4 ± 1.7% (P < 0.001) and ODI decreased from 10.7 ± 14.7 to 6.5 ± 9.0 events/hour (P < 0.001), both remained significant after Bonferroni correction. Lowest SpO₂ increased from 81.3 ± 8.7% to 83.8 ± 8.6% (P = 0.023), and CT90 decreased from 5.3 ± 11.2% to 2.9 ± 8.2% (P = 0.033), which showed nominal improvement that did not survive strict correction. Participants lost an average of 4.2 ± 1.7 kg (P < 0.001), with significant reductions in waist circumference (-6.3 ± 5.2 cm, P < 0.001) and visceral fat. Fasting glucose, insulin, HOMA-IR, triglycerides, and blood pressure also improved significantly (all P < 0.01, all secondary outcomes remained significant after Benjamini-Hochberg correction). Reduction in waist circumference correlated significantly with improvement in oxygenation indices.

A short-term, medically supervised fasting therapy significantly improved nocturnal hypoxemia, body composition, and cardiometabolic parameters in adults with overweight/obesity and suspected SRBD. The correlation between central fat loss and oxygenation improvement suggests a plausible mechanism. These promising pilot results support the need for larger randomized controlled trials to confirm the efficacy of fasting therapy as a complementary strategy for SRBD management.