# Supplements & melatonin: what the research actually says

Which sleep supplements survive contact with the evidence, at what dose, and why melatonin is a timing signal rather than a sedative.



## All studies

- **Oral magnesium supplementation for insomnia in older adults: a systematic review & meta-analysis** — Mah J, Pitre T (2021), BMC Complementary Medicine and Therapies 21(1):125. Magnesium shortened sleep onset by ~17 min; evidence quality low-to-moderate — cheap and safe, not miraculous.

- **Differential effects of DHA- and EPA-rich oils on sleep in healthy young adults: a randomized controlled trial** — Patan MJ, Kennedy DO, Husberg C, et al. (2021), Nutrients 13(1):248. DHA-rich omega-3 improved sleep efficiency and reduced latency in healthy adults with low fish intake.

- **Natural compounds for Alzheimer's disease therapy: a systematic review of preclinical and clinical studies** — Andrade S, Ramalho MJ, Loureiro JA, Pereira MDC (2018), International Journal of Molecular Sciences 19(9):2313. Background on apigenin (chamomile's active flavonoid) as a mild GABA-A modulator — the 'frontal cortex off' switch.

- **Melatonin natural health products and supplements: presence of serotonin and significant variability of melatonin content** — Erland LA, Saxena PK (2017), Journal of Clinical Sleep Medicine 13(2):275–281. Actual melatonin content ranged from −83% to +478% of the label; 26% contained serotonin — buy third-party tested.

- **Meta-analysis: melatonin for the treatment of primary sleep disorders** — Ferracioli-Oda E, Qawasmi A, Bloch MH (2013), PLoS ONE 8(5):e63773. Melatonin shortens sleep onset ~7 min and adds ~8 min of sleep — real but small effects; it is a timing signal, not a sedative.

- **The effect of magnesium supplementation on primary insomnia in elderly: a double-blind placebo-controlled clinical trial** — Abbasi B, Kimiagar M, Sadeghniiat K, Shirazi MM, Hedayati M, Rashidkhani B (2012), Journal of Research in Medical Sciences 17(12):1161–1169. 500 mg/day magnesium improved sleep time, efficiency, onset and morning cortisol/melatonin in older adults with insomnia.

- **Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality** — Howatson G, Bell PG, Tallent J, Middleton B, McHugh MP, Ellis J (2012), European Journal of Nutrition 51(8):909–916. Tart cherry juice raised urinary melatonin and modestly increased sleep time and efficiency.

- **Effect of kiwifruit consumption on sleep quality in adults with sleep problems** — Lin HH, Tsai PS, Fang SC, Liu JF (2011), Asia Pacific Journal of Clinical Nutrition 20(2):169–174. Two kiwis one hour before bed for 4 weeks improved onset, duration and efficiency — the study behind Galpin's kiwis.

- **Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: a randomized placebo-controlled pilot study** — Zick SM, Wright BD, Sen A, Arnedt JT (2011), BMC Complementary and Alternative Medicine 11:78. Chamomile extract showed modest, non-significant improvements in daytime functioning and sleep latency — level-1 design, small effect.

- **Melatonin for the prevention and treatment of jet lag** — Herxheimer A, Petrie KJ (2002), Cochrane Database of Systematic Reviews (2):CD001520. Melatonin is remarkably effective for jet lag when taken close to target bedtime — the use case Galpin endorses.

- **Melatonin treatment for age-related insomnia** — Zhdanova IV, Wurtman RJ, Regan MM, Taylor JA, Shi JP, Leclair OU (2001), Journal of Clinical Endocrinology & Metabolism 86(10):4727–4730. 0.3 mg (physiological) melatonin restored sleep efficiency as well as or better than 3 mg — the micro-dose Galpin uses.

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Educational summary of published research, not medical advice. Screening scores are not diagnoses. If a score is elevated or you feel unwell, talk to a clinician.

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