The Sleep Optimization Protocol: A Complete Sequence

Tier One: The Two That Matter Most

Fix your wake time, not your bedtime. Wake time anchors circadian phase because light exposure on waking is the dominant entraining signal. A consistent wake time, including weekends, stabilises the whole system, and bedtime then follows on its own as sleep pressure accumulates predictably. Trying to fix bedtime while wake time floats is working against the mechanism.

Sleep regularity, meaning consistency of timing rather than duration, predicts mortality and cardiometabolic outcomes in large cohort analyses, in some more strongly than duration does. It is the single most valuable sleep variable and the least attended to.

Move alcohol away from sleep. Alcohol reduces sleep onset latency and then suppresses slow-wave and REM sleep in the second half of the night, fragments sleep, worsens sleep-disordered breathing and raises heart rate through the night. Three hours before sleep is a reasonable minimum, and earlier is better.

If you do nothing else in this protocol, these two produce most of the achievable improvement for most adults.

Tier Two: Light, Temperature, Caffeine

Morning light. Ten to thirty minutes of outdoor light within an hour of waking, which is far brighter than indoor lighting even on an overcast day. This advances and stabilises circadian phase and improves evening sleepiness timing.

Evening light. Reduce bright and overhead light in the two to three hours before sleep. The intensity and spectrum both matter, and the practical version is dimmer, lower and warmer rather than blocking a specific wavelength.

Temperature. Sleep onset requires a drop in core body temperature. A cool bedroom, commonly cited around 18 degrees Celsius, supports it. A warm bath or shower one to two hours before bed also helps, counterintuitively, by driving peripheral vasodilation that increases heat loss.

Caffeine timing. Half-life is roughly 5 hours and longer in slow metabolisers, so an afternoon coffee leaves a meaningful fraction circulating at bedtime. Caffeine reduces slow-wave sleep even when it does not delay onset, which is why "it doesn't affect my sleep" is unreliable self-report. A cutoff eight to ten hours before sleep is the conservative version.

Tier Three: Behaviour and the Bed

These matter most for people whose problem is difficulty falling asleep or staying asleep rather than timing.

Get out of bed if you are awake. Lying awake trains an association between bed and wakefulness. After roughly 20 minutes, leave, do something dull in low light, and return when sleepy. This is a core component of cognitive behavioural therapy for insomnia and it works.

Restrict the bed to sleep. Working, scrolling and worrying in bed all weaken the association the previous point protects.

Keep a consistent wind-down. A repeated sequence in the last 30 to 60 minutes becomes a conditioned cue. The content matters less than the repetition.

Do not chase sleep by going to bed earlier. Extending time in bed beyond your sleep ability fragments sleep and increases time awake in bed, which is the opposite of the aim. Sleep restriction, deliberately compressing time in bed, is a counterintuitive and effective insomnia technique for this reason.

Manage the worry, not the clock. Removing visible clocks reduces the arousal that checking produces.

Tier Four: Exercise, Food and Naps

Exercise is worth separating out because its effect runs both ways. Regular training improves sleep and increases slow-wave sleep, while a single late high-intensity session can delay onset in susceptible people. The general rule is that the chronic effect is positive and the acute timing is individual.

Tier Five: Supplements, Last

Supplements are last because their effect sizes are smaller than everything above, not because they are useless.

A reasonable minimal set: glycine 3 g before bed, magnesium glycinate if dietary intake is low, and one anti-arousal option such as L-theanine or apigenin if pre-sleep mental activity is the limiting factor. Melatonin at 0.3 to 0.5 mg only for a timing problem, taken several hours before target sleep.

What to avoid: high-dose melatonin, proprietary blends with undisclosed doses, and anything relied upon nightly for months without addressing why it is needed. Nightly dependence on any sleep aid is a signal that something above it in the sequence is unresolved.

The supplement guide covers the individual compounds in more detail. The point of placing them fifth is that a person who starts here, as most people do, is optimising the smallest available variable.

When to Stop Optimising and Get Assessed

Some sleep problems are not optimisation problems, and continuing to adjust a protocol delays the thing that would actually help.

Get clinical assessment for: loud snoring, witnessed pauses in breathing, waking gasping, or unrefreshing sleep with adequate duration, all of which suggest sleep-disordered breathing, which is common, underdiagnosed and consequential for cardiovascular and metabolic health. Also for persistent insomnia beyond three months, for excessive daytime sleepiness despite adequate opportunity, for restless legs symptoms, and for any dramatic dream enactment behaviour.

Sleep-disordered breathing in particular cannot be optimised around. It suppresses slow-wave sleep, raises sympathetic tone through the night, and is associated with hypertension, arrhythmia and metabolic dysfunction. Every item in this protocol is less important than identifying it if it is present.

For chronic insomnia, cognitive behavioural therapy for insomnia is the guideline first-line option and outperforms pharmacological approaches for durability. Several structured digital programmes exist and have trial support.

The general principle: optimise for four to six weeks, and if the problem persists despite tiers one and two being genuinely in place, the answer is an assessment rather than another compound.