Sleep: What It Does and What Happens Without It

1. What sleep is for. Memory consolidation, hormone regulation, immune function, metabolic regulation and cellular repair. Teach it as active maintenance, not downtime. [Dr Haq to add examples from practice.]
2. How much. A joint consensus statement of the American Academy of Sleep Medicine and the Sleep Research Society recommends that adults aged 18–60 regularly sleep seven or more hours per night for optimal health, noting that individual needs vary (Watson et al., 2015). Regular sleep under seven hours is linked to weight gain, diabetes, hypertension, depression and higher mortality risk in that statement.
3. Sleep and mortality. A meta-analysis of 16 prospective studies (1,382,999 participants, 112,566 deaths) found both short sleep (relative risk 1.12) and long sleep (relative risk 1.30) were associated with higher all-cause mortality (Cappuccio et al., 2010). Limits: sleep was self-reported, usually measured once, and the studies are observational, so cause and effect cannot be assumed. Long sleep is often a marker of illness, not a cause.
4. Sleep and ageing. Short or fragmented sleep is associated with metabolic and inflammatory changes. Genetic evidence also links short sleep to shorter leukocyte telomere length; this is an emerging association and causation is unproven.
5. Circadian rhythm. The body clock is set mainly by light and timing. Regular wake time, morning daylight and reduced evening light are the most consistently taught anchors. Shift work and late screen use disrupt it.
6. Assessing sleep. Ask about duration, timing, regularity, time to fall asleep, night waking, snoring or witnessed apnoea pauses, daytime sleepiness, and what the person thinks is wrong (ICE, Module 5 links). A simple one-week sleep diary is a legitimate coach tool.
7. When to refer. Loud snoring with witnessed pauses or marked daytime sleepiness (possible sleep apnoea), insomnia lasting weeks despite good habits, restless legs, mood changes, or sleep problems alongside red-flag symptoms (Lesson 4.5).
8. Practical foundations. Regular timing, morning light, caffeine and alcohol timing, a wind-down routine, a cool dark room. Teach as options to try, with the person choosing.

A 58-year-old client reports exhaustion despite "eight hours in bed" and a partner says she snores loudly. What do you do?

What is the one sleep change you would most resist making yourself, and what does that tell you about asking clients?

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