Recovery6 min read

Intermittent Fasting and Sleep Quality

Muhammad UsamaUpdated 2024-03-10

Meal timing exerts a profound influence on sleep latency, nocturnal heart rate variability (HRV), and stage 3/4 deep restorative sleep.

1. The Thermic Cost of Late Digestion

Digesting complex macronutrients raises core body temperature. For sleep onset to occur normally, circadian biology requires a drop of approximately 1°C in core body temperature.

Finishing dinner 3 to 4 hours before bedtime permits gastric emptying, allowing resting heart rate to lower earlier in the night.

Key Rule: A 3-hour digestive buffer before sleep improves sleep latency and nocturnal HRV.

2. Gastroesophageal Reflux Prevention

Lying supine with a full stomach causes nocturnal acid reflux and micro-arousals that fragment sleep architecture.