Study on the Mechanism of Central Obesity Induced by Sleep Restriction and the Therapeutic Effect of n-3 Polyunsaturated Fatty Acid: a Randomized, Double-blind, Placebo-controlled Trial (COSPA Study)

This randomized, double-blind, placebo-controlled trial aims to investigate whether n-3 polyunsaturated fatty acid (PUFA) supplementation attenuates abdominal visceral fat accumulation induced by experimental sleep restriction. Forty healthy adults aged 18-50 years will be randomly assigned to receive n-3 PUFA supplementation (approximately 1.1 g/day of EPA and DHA) or a matching placebo. The intervention will last approximately 75 days, including a 19-day residential sleep protocol consisting of 3 adaptation days, 14 days of sleep restriction (4 hours per night), and 2 recovery days. The primary outcome is the change in abdominal visceral adipose tissue area measured by CT. Additional assessments include body composition, metabolic and inflammatory markers, gut microbiota, microbial metabolites, and adipose tissue molecular profiles.