Research

Hormonal

Continuous Positive Airway Pressure (CPAP) therapy for Obstructive Sleep Apnoea (OSA) results in a statistically significant, albeit small, increase in body weight and Body Mass Index (BMI) compared to control conditions.

If you start CPAP for sleep apnea, expect a small amount of weight gain (average ~0.4 kg in the studies, but variable). This is likely because your body is no longer burning extra energy fighting breathing interruptions and your sleep hormones (growth hormone/cortisol) are normalizing. To counter this, proactively combine CPAP with standard weight management strategies like diet and exercise, rather than stopping CPAP.

StrongSupportsHIGH confidence
The fixed-effects meta-analysis revealed that CPAP promoted significant increase on BMI (Hedges’ g=0.14, 95% CI 0.07 to 0.21, I2=16.2%) and weight (Hedges’ g=0.17, 95% CI 0.10 to 0.24, I2=0%).
Luciano F. Drager et al. · Thorax · 2014

Why this rating

Based on a meta-analysis of 25 randomized controlled trials involving 3,181 patients, providing high-level evidence.

Source

Effects of CPAP on body weight in patients with obstructive sleep apnoea: a meta-analysis of randomised trials

Luciano F. Drager et al. · Thorax · 2014

DOI 10.1136/thoraxjnl-2014-205361

Meta-analysis · 25 studiesCited 271×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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