How to fall asleep faster: the validated levers

Falling asleep depends on a precise physiological cascade: a drop in body temperature, the release of melatonin, a fall in cortisol. Three families of causes disrupt this mechanism: cognitive hyperarousal (stress, rumination), stimulants taken too late (caffeine, alcohol, nicotine), and desynchronisers (blue light, irregular schedules, late naps). The levers that follow act on all three fronts.

Stabilise your wake-up time

This is the most powerful and the least costly lever. The circadian system rests on regularity: going to bed and getting up at consistent times, weekends included, strengthens the evening secretion of melatonin. Set a single wake-up time and do not stray from it by more than 60 minutes.

Switch off screens before bed

The blue light from screens suppresses melatonin secretion and delays sleep onset. Turn screens off 30 to 60 minutes before bed and favour reading, conversation or listening to music. Teenagers and young adults, who are more sensitive to this light, feel the effect more strongly.

Get out into the morning light

The circadian system sets itself mainly by morning light. A 15 to 30 minute exposure to daylight before 10 a.m. re-anchors the body clock and brings forward the evening secretion of melatonin, which shortens sleep-onset latency that very evening. Even under an overcast sky, outdoor light is far brighter than that of a well-lit office.

A cooler bedroom

Sleep onset begins with a fall in core body temperature of about 0.5 °C. A bedroom at 17-19 °C aids this heat dissipation, whereas a room at 22 °C or above delays sleep onset and fragments deep sleep. A lukewarm shower 60 to 90 minutes before bed speeds up the temperature drop.

Caffeine and alcohol, two classic traps

Caffeine blocks adenosine receptors for 5 to 6 hours in a healthy adult: better to stop drinking it in early afternoon. Alcohol shortens sleep-onset latency but degrades sleep quality in the second half of the night, with more nocturnal awakenings. Avoid it in the three hours before bed.

Going straight from activity to bed does not work. The body needs a 30 to 60 minute buffer to switch over to rest: dimmed lights, a quiet activity, the bedroom made ready, no work e-mails and no anxiety-inducing news. Slow breathing (cardiac coherence) helps activate the parasympathetic system before bed.

Once these levers are in place, some adults add a CBD product to their evening routine, in the same way as a soothing herbal tea. CBD is not a sleeping pill, and no French authority has validated any claim about sleep: at most it belongs to the wind-down ritual, never to a treatment.

Allow two to three weeks to gauge an effect on sleep-onset latency. If after that period your latency still exceeds 30 minutes, or if daytime sleepiness sets in, see your GP. Chronic insomnia calls for medical care, ideally through cognitive behavioural therapy for insomnia (CBT-I), regarded as the reference treatment ahead of any medication.

How long do these levers take to work?

Allow two to three weeks for regular schedules and morning light exposure. One-off adjustments, such as the bedroom temperature, can have an effect from the very first night.

If you wake in the night, is it better to stay in bed or get up?

If you have been awake for more than 20 to 30 minutes, it is better to get up for a quiet activity in a dimly lit room, then go back to bed as soon as drowsiness returns.

Are melatonin supplements useful?

At a low dose (0.5 to 2 mg), they mainly help resynchronise the rhythm after a time-zone shift. For ordinary insomnia, their value is more limited. Above 2 mg, melatonin is classed as a medicine in France.

Can CBD replace a sleeping pill?

No. It does not share the mechanism of action of hypnotics and holds no authorisation as a medicine. It belongs to a wellbeing routine, not to a medical treatment.

CBD is not a medicine. If sleep problems persist, consult a healthcare professional.

• EFSA Journal 2026 — Update statement CBD novel food — primary
• ANSM — Thematic file on medical cannabis — primary
• ANSM — Progress report, Feb. 2024 (final year of the trial) — primary