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Sleep & Recovery

Evidence-based natural approaches to sleep quality, circadian rhythm, and overnight recovery — from key nutrients to sleep hygiene strategies.

This page is for educational purposes only. It does not replace medical advice. If you have a sleep disorder such as sleep apnoea or insomnia, always work with your doctor.

Key nutrients for sleep and recovery

The compounds with the strongest evidence for improving sleep quality and overnight restoration.

Magnesium Glycinate

Grade A

200–400mg before bed

Activates GABA receptors and reduces cortisol. Reduces sleep onset time by 17 minutes and increases sleep efficiency in older adults in RCTs. Glycinate form has superior absorption and minimal laxative effect.

Melatonin

Grade A

0.5–3mg, 30–60 min before bed

The most evidence-supported sleep supplement. Most effective for circadian rhythm disorders, jet lag, and shift work. Lower doses (0.5–1mg) are as effective as higher doses with fewer side effects.

L-Theanine

Grade B

100–200mg before bed

Increases alpha brain wave activity — the relaxed-alert state that facilitates sleep onset. Reduces anxiety without sedation. Synergistic with magnesium. Found naturally in green tea.

Ashwagandha (KSM-66)

Grade B

300–600mg before bed

Reduces cortisol by 27% in RCTs. Improves sleep quality, sleep onset, and total sleep time in adults with insomnia. Adaptogenic — normalises HPA axis dysregulation from chronic stress.

Glycine

Grade B

3g before bed

Lowers core body temperature — a key trigger for sleep onset. Improves subjective sleep quality and reduces daytime fatigue in RCTs. Also supports collagen synthesis and liver detoxification.

Tart Cherry (Montmorency)

Grade B

480ml juice or 480mg extract

Natural source of melatonin and tryptophan. Increases total sleep time by 84 minutes in older adults in RCTs. Anti-inflammatory effects also support overnight muscle recovery.

6 natural strategies with strong evidence

Ranked by effect size across the best available research.

⏰
#1

Consistent sleep and wake times

The single most effective sleep intervention. Irregular sleep timing disrupts circadian rhythm and reduces sleep quality even when total hours are adequate. Consistent wake time (even on weekends) is more important than consistent bedtime.

🌅
#2

Morning light exposure

Bright light (ideally sunlight) within 30 minutes of waking sets the circadian clock and advances melatonin onset by 1–2 hours. 10 minutes of outdoor light is more effective than any light therapy device. Reduces time to fall asleep by 30–40 minutes.

📵
#3

Reduce blue light after sunset

Blue light suppresses melatonin by up to 85% for 3+ hours. Blue-light-blocking glasses or screen filters after 9pm restore melatonin onset. Dimming all lights in the evening is as effective as blue-light blocking alone.

❄️
#4

Keep the bedroom cool

Core body temperature must drop 1–2°F to initiate sleep. Optimal bedroom temperature is 65–68°F (18–20°C). A warm bath or shower 1–2 hours before bed paradoxically improves sleep by accelerating the subsequent temperature drop.

🚫
#5

Avoid alcohol within 3 hours of bed

Alcohol reduces REM sleep by 24% in the first half of the night and causes rebound arousal in the second half. Even 1–2 drinks significantly impairs sleep architecture and overnight memory consolidation.

🏃
#6

Regular aerobic exercise

Exercise improves sleep quality, reduces sleep onset time, and increases slow-wave (deep) sleep. Morning or afternoon exercise is optimal — vigorous exercise within 2 hours of bedtime can delay sleep onset in some individuals.

Factors that disrupt sleep

The modifiable factors that impair sleep quality — and what the evidence says about correcting them.

Irregular sleep scheduleSet a consistent wake time 7 days a week. This is the highest-leverage single change for sleep quality.
Evening light exposureDim all lights after 9pm. Use blue-light-blocking glasses or screen filters. Avoid bright overhead lighting.
Caffeine after 2pmCaffeine has a 5–7 hour half-life. Afternoon caffeine reduces deep sleep by 20% even when sleep onset is unaffected.
Chronic stress / high cortisolAshwagandha, magnesium, MBSR, and regular exercise all reduce cortisol and improve sleep quality.
AlcoholEliminate alcohol within 3 hours of bed. Even moderate amounts significantly impair sleep architecture.
Sleep apnoeaAffects 25% of adults — most undiagnosed. Symptoms: snoring, morning headaches, daytime fatigue. Requires medical evaluation and treatment.

Ready to improve your sleep?

The Sleep Tracker helps you log sleep patterns, identify disruptions, and build better sleep habits over time.

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