Fix your sleep and half your problems disappear

Sleep is not lost time

During sleep, your brain consolidates memories and your body carries out repair and hormone regulation. Animal research suggests the brain also clears waste products more efficiently during sleep. Cutting sleep short has measurable effects:

• Hormones. In a JAMA study, healthy young men who slept 5 hours a night for one week had 10–15% lower daytime testosterone.
• Appetite. In a study of healthy young men, two nights of 4-hour sleep lowered leptin (a hormone that signals fullness), raised ghrelin (a hormone that drives hunger), and increased hunger, especially for calorie-dense, high-carbohydrate foods.

This means that if you’re struggling to lose weight, short sleep may be part of the reason.

How much you need

The American Academy of Sleep Medicine and the Sleep Research Society recommend at least 7 hours a night for adults. The National Sleep Foundation recommends 7–9 hours. A small number of people genuinely need less, but it’s rare. Most people who “only need five hours” are simply used to being tired.

A simple routine that helps

• Keep a fixed wake time, including weekends. This anchors your body clock.
• Get daylight soon after waking, ideally outdoors.
• Stop caffeine at least 6 hours before bed. In one study, a large dose (400 mg, roughly 3–4 cups of brewed coffee) taken 6 hours before bed still cut total sleep by about an hour.
• Dim lights and screens in the last hour before bed.
• Keep your bedroom cool, dark and quiet.

Consistency matters more than any single trick. If you only change one thing, make it a regular wake-up time.

When to see a doctor

See a doctor if poor sleep persists for three months or more and affects your day. Also see one if you snore loudly, stop breathing or gasp during sleep, or feel very sleepy during the day despite enough time in bed. Loud snoring with pauses in breathing can be a sign of sleep apnoea. For long-term insomnia, the American College of Physicians recommends cognitive behavioural therapy for insomnia (CBT-I) as the first treatment, before sleeping pills.

References

1. 1.Recommended amount of sleep for a healthy adult: joint consensus statement of the AASM and Sleep Research Society. Sleep, 2015.doi:10.5665/sleep.4716
2. 2.National Sleep Foundation's sleep time duration recommendations. Sleep Health, 2015.doi:10.1016/j.sleh.2014.12.010
3. 3.Sleep curtailment in healthy young men is associated with decreased leptin, elevated ghrelin, and increased hunger and appetite. Annals of Internal Medicine, 2004.doi:10.7326/0003-4819-141-11-200412070-00008
4. 4.Effect of 1 week of sleep restriction on testosterone levels in young healthy men. JAMA, 2011.doi:10.1001/jama.2011.710
5. 5.Sleep drives metabolite clearance from the adult brain. Science, 2013.doi:10.1126/science.1241224
6. 6.Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. Journal of Clinical Sleep Medicine, 2013.doi:10.5664/jcsm.3170
7. 7.Management of chronic insomnia disorder in adults: clinical practice guideline (American College of Physicians). Annals of Internal Medicine, 2016.doi:10.7326/M15-2175

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Educational information, not medical advice. See a doctor for anything persistent or severe. All content is original to Venva.