Sleep is not optional
Adults need seven or more hours of sleep a night for health, according to the joint consensus of the American Academy of Sleep Medicine and the Sleep Research Society1. Across 1.3 million people, short sleepers had a 12% higher risk of death and very long sleepers 30% higher, the latter usually a sign of underlying illness2.
The effect is fast. After six nights of four hours' sleep, healthy young men handled glucose like people on the way to diabetes, with higher evening cortisol3. Tired people are hungrier, move less and choose worse food. If your blood sugar, blood pressure or weight will not move, look at your sleep first.
“It is vain for you to rise up early, to stay up late, eating the bread of toil; for he gives sleep to his loved ones” (Psalm 127:2). Sleep is an act of trust: the world carries on without you, and God does not sleep.
How to sleep better
Keep the same waking time every day. Get outdoor light in the first hour. Stop caffeine by midday. Keep the bedroom cool, dark and free of screens. Finish eating and drinking alcohol three hours before bed. If you snore heavily, stop breathing in your sleep or wake unrefreshed despite enough hours, ask your doctor about sleep apnoea; it is common, treatable, and drives blood pressure and blood sugar.
One day in seven
God rested on the seventh day and made it holy before there was any sin to recover from (Genesis 2:2-3). Rest is built into creation, and into every sound training plan: muscle is rebuilt between sessions, not during them.
When Elijah lay down under the juniper tree asking to die, God's first answer was not a sermon. An angel gave him bread, water and sleep, twice (1 Kings 19:5-8). Sometimes the most spiritual thing you can do is eat a proper meal and go to bed.
References
- Watson NF et al. Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society. Sleep. 2015. PubMed 26039963 · Full text
- Cappuccio FP et al. Sleep duration and all-cause mortality: a systematic review and meta-analysis of prospective studies. Sleep. 2010. PubMed 20469800 · Full text
- Spiegel K et al. Impact of sleep debt on metabolic and endocrine function. Lancet. 1999. PubMed 10543671 · Full text