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Dr. Grey AI

Condition

Sleep Quality

Sleep quality reflects how easily you fall asleep, how well you stay asleep, and how rested you feel, all guided by the brain's body clock and calming signals such as GABA. Tryptophan has the most support: trials found people fell asleep sooner, especially those with mild insomnia, while small studies of the peptide DSIP found total sleep time went up. Still, evidence beyond tryptophan is limited, and studies were small or mostly animal work.

Sources: PMID 16539679; PMID 6145137

Supplements studied
4
Medicines and peptides
3
Graded outcomes
13

Evidence by supplement

  • Strong
  • Moderate
  • Limited
  • Very limited

4 supplements

Tryptophan: outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Sleep Latency

Doses ≥1g decrease sleep latency; best results in mild insomnia

Improves (the measure goes down)Moderate effect800 people
Subjective Sleepiness

Increased rated subjective sleepiness at doses ≥1g

Improves (the measure goes up)Moderate effect400 people
Apigenin: outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Sleep Quality

Small Improvement (chamomile extract studies)

Improves (the measure goes up)Small effect120 people
Daytime Functioning

Trend toward improvement, not statistically significant

Improves (the measure goes up)Small effect34 people
Magnolia Bark (Magnolia officinalis): outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Sleep Quality

Preclinical: Honokiol (10-20 mg/kg) shortened sleep latency to NREM sleep and increased NREM sleep amount by modulating GABAA benzodiazepine site. Clinical evidence limited but mechanism supports sleep promotion without next-day sedation.

Improves (the measure goes up)Moderate effect

GABA

  • Sleep Latency: improves
  • Non-REM Sleep Duration: improves
GABA: outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Sleep Latency

Moderate Decrease - 100mg GABA reduced time to fall asleep

Improves (the measure goes down)Moderate effect120 people
Non-REM Sleep Duration

Small Increase in non-REM sleep duration

Improves (the measure goes up)Small effect60 people

Prescription medicines and peptides studied, for context

These are not supplements. Most need a prescription, and some are research compounds with no approved use. They are listed so the supplement evidence above can be read against them.

3 medicines and peptides

CJC-1295

  • Slow-Wave Sleep Duration: improves
CJC-1295: outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Slow-Wave Sleep Duration

Enhanced deep sleep duration (GHRH analog data)

Improves (the measure goes up)Moderate effect17 studies35 people

DSIP (Delta Sleep-Inducing Peptide)

  • Sleep Onset Latency: improves
  • Total Sleep Time: improves
  • Delta Wave Activity: improves
DSIP (Delta Sleep-Inducing Peptide): outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Sleep Onset Latency

Moderate Decrease

Improves (the measure goes down)Moderate effect12 studies85 people
Total Sleep Time

Moderate Increase

Improves (the measure goes up)Moderate effect12 studies92 people
Delta Wave Activity

Moderate Increase

Improves (the measure goes up)Moderate effect1 study45 people

Epitalon

  • Melatonin Production: improves
  • Sleep Architecture: improves
Epitalon: outcomes studied for Sleep Quality
GradeOutcomeEffectSizeStudiesPeopleStudies list
Melatonin Production

Moderate increase in nocturnal melatonin

Improves (the measure goes up)Moderate effect5 studies78 people
Sleep Architecture

Small improvement in sleep quality

Improves (the measure goes up)Small effect2 studies42 people

What the published studies found

19 automated readings

Automated reading of the published studies (Decosa evidence engine), for outcomes Dr. Grey has not graded yet. It is not a Dr. Grey grade and does not change one. How it is read

Key findings

  • Sleep LatencyTryptophanImproves (the measure goes down)
  • Subjective SleepinessTryptophanImproves (the measure goes up)
  • Sleep QualityApigeninImproves (the measure goes up)

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Or shop one supplement

The supplement graded A or B for Sleep Quality. Each opens third-party tested products for that supplement.

  • Grade B

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Studies cited

100 studies from PubMed

  1. Analysis of growth hormone releasing hormone and its analogs in urine using nano liquid chromatography coupled with quadrupole/orbitrap mass spectrometry.Journal of pharmaceutical and biomedical analysis, 2026 · PMID 41138283
  2. Overview of Epitalon-Highly Bioactive Pineal Tetrapeptide with Promising PropertiesInt J Mol Sci, 2025 · PMID 40141333
  3. The Antioxidant Tetrapeptide Epitalon Enhances Delayed Wound Healing in an in Vitro Model of Diabetic Retinopathy.Stem cell reviews and reports, 2025 · PMID 40493162
  4. Neuropharmacological potential of honokiol and its derivatives from Chinese herb Magnolia species: understandings from therapeutic viewpointChin Med, 2023 · PMID 37940681
  5. Honokiol-Rich Magnolia officinalis Bark Extract Attenuates Trauma-Induced Neuropathic PainAntioxidants (Basel), 2023 · PMID 37629145
  6. Early detection of cannabinoids in biological samples based on their affinity interaction with the growth hormone secretagogue receptor.Talanta, 2022 · PMID 34736642
  7. An antibody-free, ultrafiltration-based assay for the detection of growth hormone-releasing hormones in urine at low pg/mL concentrations using nanoLC-HRMS/MS.Journal of pharmaceutical and biomedical analysis, 2022 · PMID 35298973
  8. Peptides Regulating Proliferative Activity and Inflammatory Pathways in the Monocyte/Macrophage THP-1 Cell Line.International journal of molecular sciences, 2022 · PMID 35408963
  9. Epitalon protects against post-ovulatory aging-related damage of mouse oocytes in vitro.Aging, 2022 · PMID 35413689
  10. Dietary gamma-aminobutyric acid (GABA) induces satiation by enhancing the postprandial activation of vagal afferent nervesNutrients, 2022 · PMID 35705389
  11. Advances in the detection of growth hormone releasing hormone synthetic analogs.Drug testing and analysis, 2021 · PMID 34665524
  12. A honokiol-enriched Magnolia officinalis Rehder & E.H. Wilson. bark extract possesses anxiolytic-like activity with neuroprotective effect through the modulation of CB1 receptorJ Ethnopharmacol, 2021 · PMID 33950239
  13. Comparison of magnetic bead surface functionalities for the immunopurification of growth hormone-releasing hormones prior to liquid chromatography-high resolution mass spectrometry.Journal of chromatography. A, 2020 · PMID 32971474
  14. Effects of oral gamma-aminobutyric acid (GABA) administration on stress and sleep in humans: a systematic reviewFront Neurosci, 2020 · PMID 33041752
  15. An immuno polymerase chain reaction screen for the detection of CJC-1295 and other growth-hormone-releasing hormone analogs in equine plasma.Drug testing and analysis, 2019 · PMID 30489688
  16. Supplementation of gamma-aminobutyric acid (GABA) affects temporal, but not spatial visual attentionBrain Cogn, 2017 · PMID 28638600
  17. Netnography of Female Use of the Synthetic Growth Hormone CJC-1295: Pulses and Potions.Substance use & misuse, 2016 · PMID 26771670
  18. Qualitative identification of growth hormone-releasing hormones in human plasma by means of immunoaffinity purification and LC-HRMS/MS.Analytical and bioanalytical chemistry, 2016 · PMID 26879649
  19. Expanded test method for peptides >2 kDa employing immunoaffinity purification and LC-HRMS/MS.Drug testing and analysis, 2015 · PMID 26382721
  20. Neurotransmitters as food supplements: the effects of GABA on brain and behaviorFront Psychol, 2015 · PMID 26500584
  21. Effect of delta sleep-inducing peptide on the expression of antioxidant enzyme genes in the brain and blood of rats during physiological aging.Bulletin of experimental biology and medicine, 2014 · PMID 25257425
  22. [Main mechanisms of rhabdomyolysis-caused kidney injury and their correction by organospecific peptides].Biofizika, 2014 · PMID 25730989
  23. [Peptides and CCL11 and HMGB1 as molecular markers of aging: literature review and own data].Advances in gerontology = Uspekhi gerontologii, 2014 · PMID 25826983
  24. Effect of Magnolia officinalis and Phellodendron amurense (Relora®) on cortisol and psychological mood state in moderately stressed subjectsJ Int Soc Sports Nutr, 2013 · PMID 23924268
  25. Neuro-modulating effects of honokiol: a reviewFront Neurol, 2013 · PMID 24012603
  26. Immunoaffinity purification of peptide hormones prior to liquid chromatography-mass spectrometry in doping controls.Methods (San Diego, Calif.), 2012 · PMID 21871962
  27. Effect of delta sleep-inducing peptide on oxidative modification of proteins in rat tissues and blood during physiological aging.Bulletin of experimental biology and medicine, 2012 · PMID 22866315
  28. Effects of melatonin and epithalamin on the content of protein and lipid peroxidation products in rat cortex and hippocampus under conditions of acute hypoxia.Bulletin of experimental biology and medicine, 2012 · PMID 23330089
  29. [Peptide Ala-Glu-Asp-Gly and interferon gamma: their role in immune response during aging].Advances in gerontology = Uspekhi gerontologii, 2012 · PMID 23289226
  30. Melatonin and pineal gland peptides are able to correct the impairment of reproductive cycles in rats.Current aging science, 2012 · PMID 23237594
  31. The natural products magnolol and honokiol are positive allosteric modulators of both synaptic and extra-synaptic GABA(A) receptorsNeuropharmacology, 2012 · PMID 22445602
  32. Honokiol promotes non-rapid eye movement sleep via the benzodiazepine site of the GABA(A) receptor in miceBr J Pharmacol, 2012 · PMID 22796355
  33. Safety and tolerability of subcutaneous CJC-1295 in healthy adults: Phase I clinical trialPhase I Trial Report, 2010 · PMID 20547587
  34. Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjectsGrowth Horm IGF Res, 2009 · PMID 19386527
  35. Pulsatile vs continuous growth hormone secretion: clinical implicationsHorm Res, 2008 · PMID 18166110
  36. [Endogenous anticonvulsants: neuropeptide Y and delta sleep inducing peptide].Medicinski pregled, 2008 · PMID 19102071
  37. Effect of a proprietary Magnolia and Phellodendron extract on stress levels in healthy women: a pilot, double-blind, placebo-controlled clinical trialNutr J, 2008 · PMID 18426577
  38. Interaction of Delta sleep-inducing peptide and valproate on metaphit audiogenic seizure model in rats.Cellular and molecular neurobiology, 2007 · PMID 17957464
  39. Normalizing effect of the pineal gland peptides on the daily melatonin rhythm in old monkeys and elderly peopleAdv Gerontol, 2007 · PMID 17969590
  40. [Age-related changes of exercise capacity and some biochemical indices of rat muscles under influence of different light conditions and pineal preparations].Advances in gerontology = Uspekhi gerontologii, 2007 · PMID 17969589
  41. Antioxidant properties of geroprotective peptides of the pineal gland.Archives of gerontology and geriatrics, 2007 · PMID 17317455
  42. Effect of epithalamin on the rhythm of immune and endocrine systems functioning in patients with chronic coronary disease.Bulletin of experimental biology and medicine, 2007 · PMID 18214303
  43. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adultsJ Clin Endocrinol Metab, 2006 · PMID 16352683
  44. Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouseAm J Physiol Endocrinol Metab, 2006 · PMID 16822960
  45. Growth hormone-releasing hormone and growth hormone secretagogues: clinical applicationsJ Clin Endocrinol Metab, 2006 · PMID 16618948
  46. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog.The Journal of clinical endocrinology and metabolism, 2006 · PMID 17018654
  47. Delta sleep-inducing peptide (DSIP): a still unresolved riddleJ Neurochem, 2006 · PMID 16539679
  48. Delta-sleep-inducing peptide potentiates anticonvulsive activity of valproate against metaphit-provoked audiogenic seizure in rats.Pharmacology, 2006 · PMID 16645330
  49. Anti-aging peptide bioregulators induce reactivation of chromatin.Georgian medical news, 2006 · PMID 16705247
  50. [Comparative study of the effects of melatonin and epitalon on the protracted memory under the shuttle labyrinth test conditions in rats in the course of aging].Eksperimental'naia i klinicheskaia farmakologiia, 2006 · PMID 17209456
  51. [Influence of light regimens, melatonin, and epitalon on amylase activity in the pancreas and small intestine in rats of different age].Advances in gerontology = Uspekhi gerontologii, 2006 · PMID 17152723
  52. [Effect of age, different light conditions, melatonin, and epitalon on lysosomal proteinase activity in the liver and kidneys of rats].Advances in gerontology = Uspekhi gerontologii, 2006 · PMID 17152724
  53. Effect of a proprietary Magnolia and Phellodendron extract on weight management: a pilot, double-blind, placebo-controlled clinical trialAltern Ther Health Med, 2006 · PMID 16454147
  54. Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analogEndocrinology, 2005 · PMID 15817669
  55. Antiepileptic activity of delta sleep-inducing peptide and its analogue in metaphit-provoked seizures in rats.Seizure, 2005 · PMID 15911358
  56. Pineal peptides restore the age-related disturbances in hormonal functions of the pineal gland and the pancreasExp Gerontol, 2005 · PMID 15664732
  57. [Effect of epitalon and melatonin on life span and spontaneous carcinogenesis in senescence accelerated mice (SAM)].Voprosy onkologii, 2005 · PMID 15909815
  58. Antigen-induced changes in the endocrine function of the thymus in CBA mice during aging: role of peptide factors released by the pineal gland.Bulletin of experimental biology and medicine, 2005 · PMID 16224593
  59. Delta sleep-inducing peptide and its tetrapeptide analogue alleviate severity of metaphit seizures.Pharmacology, biochemistry, and behavior, 2004 · PMID 14751449
  60. [Behavioral and electroencephalographic effects of delta sleep inducing peptide and its analogue on metaphit-induced audiogenic seizures in rats].Srpski arhiv za celokupno lekarstvo, 2004 · PMID 15938222
  61. Effect of peptide preparation epithalamin on circadian rhythm of epiphyseal melatonin-producing function in elderly peopleBull Exp Biol Med, 2004 · PMID 15452611
  62. Effects of pineal peptides on circadian dynamics of spermatogonia proliferation in albino rats.Bulletin of experimental biology and medicine, 2004 · PMID 15455095
  63. Effect of epithalamin on circadian relationship between the endocrine function of the thymus and melatonin-producing function of the pineal gland in elderly people.Bulletin of experimental biology and medicine, 2004 · PMID 15455130
  64. [The pineal gland's peptides factors and the rhythms of functions of the thymus and bone marrow in animals during aging].Advances in gerontology = Uspekhi gerontologii, 2004 · PMID 15490729
  65. [Effect of epitalon on the immunity and hemostasis in hypophysectomized chicken and old hens].Advances in gerontology = Uspekhi gerontologii, 2004 · PMID 15490730
  66. Pharmacokinetics, safety, and tolerability of increasing repeat doses of CJC-1295 in healthy volunteersClinical Trial Data, 2003 · PMID 12788835
  67. Delta sleep inducing peptide (DSIP): effect on respiration activity in rat brain mitochondria and stress protective potency under experimental hypoxiaPeptides, 2003 · PMID 12668217
  68. Epithalon peptide induces telomerase activity and telomere elongation in human somatic cellsBull Exp Biol Med, 2003 · PMID 12937682
  69. The role of pineal gland in breast cancer development.Critical reviews in oncology/hematology, 2003 · PMID 12791421
  70. [Effect of epithalamin on free-radical reactions in the formed elements of blood from breast cancer patients].Voprosy onkologii, 2003 · PMID 12926216
  71. Effect of Epitalon on biomarkers of aging, life span and spontaneous tumor incidence in female Swiss-derived SHR mice.Biogerontology, 2003 · PMID 14501183
  72. [Regulating effect of pineal gland peptides on development of T-lymphocytes in CBA aging mice: role of microenvironment of immune system organs and neuroendocrine factors].Advances in gerontology = Uspekhi gerontologii, 2003 · PMID 14743608
  73. Epitalon and colon carcinogenesis in rats: proliferative activity and apoptosis in colon tumors and mucosa.International journal of molecular medicine, 2003 · PMID 12964022
  74. Peptides and AgeingNeuro Endocrinol Lett, 2002 · PMID 12374906
  75. Aging of the pineal glandUsp Fiziol Nauk, 2002 · PMID 12096440
  76. Inhibitory effect of the peptide epitalon on the development of spontaneous mammary tumors in HER-2/neu transgenic mice.International journal of cancer, 2002 · PMID 12209581
  77. Epithalon decelerates aging and suppresses development of breast adenocarcinomas in transgenic her-2/neu mice.Bulletin of experimental biology and medicine, 2002 · PMID 12459848
  78. Effects of epithalon on activities gastrointestinal enzymes in young and old rats.Bulletin of experimental biology and medicine, 2002 · PMID 12360355
  79. Growth hormone-releasing peptides, ghrelin, and growth hormone secretagoguesCurr Opin Endocrinol Diabetes, 2001 · PMID 11701431
  80. Synthetic tetrapeptide epitalon restores disturbed neuroendocrine regulation in senescent monkeys.Neuro endocrinology letters, 2001 · PMID 11524632
  81. Effect of pineal tetrapeptide on antioxidant defense in Drosophila melanogaster.Bulletin of experimental biology and medicine, 2000 · PMID 10977918
  82. Studies of cytokines in nerve tissue cultures.Neuroscience and behavioral physiology, 2000 · PMID 10970020
  83. Peptide bioregulators inhibit apoptosis.Bulletin of experimental biology and medicine, 2000 · PMID 11276315
  84. Effects of intranasal growth hormone-releasing hormone on sleep and sleep-related growth hormone release in aged menNeuropsychobiology, 1999 · PMID 10524511
  85. [Long-term results of comprehensive treatment for cervical cancer with poor prognosis].Voprosy onkologii, 1999 · PMID 10532103
  86. Honokiol, a putative anxiolytic agent extracted from magnolia bark, has no diazepam-like side-effects in miceJ Pharm Pharmacol, 1999 · PMID 10197425
  87. Opioid detoxification with delta sleep-inducing peptide: results of an open clinical trialJ Clin Psychopharmacol, 1998 · PMID 9617990
  88. [Effect of melatonin and epithalamin on the antioxidant defense system activity in rats].Doklady Akademii nauk, 1997 · PMID 9147634
  89. Effect of melatonin and pineal peptide preparation epithalamin on life span and free radical oxidation in Drosophila melanogaster.Mechanisms of ageing and development, 1997 · PMID 9226628
  90. [Comparison of the antioxidant properties of melatonin, epithalamin, and glutathione by the method of luminol-dependent chemiluminescence in vitro].Doklady Akademii nauk, 1997 · PMID 9376803
  91. [Effect of melatonin and epithalamin on life span and lipid peroxidation in Drosophila melanogaster].Doklady Akademii nauk, 1997 · PMID 9147629
  92. GHRH increases slow-wave sleep and REM sleep in humansEur J Endocrinol, 1996 · PMID 8636311
  93. [Melatonin and epithalamin extinguishes the lipid peroxidation process in rats].Doklady Akademii nauk, 1996 · PMID 8924857
  94. Delta-sleep-inducing peptide sequels in the mechanisms of resistance to emotional stressAnn N Y Acad Sci, 1995 · PMID 8597403
  95. [Melatonin and epithalamin inhibit the process of free radical oxidation in rats].Doklady Akademii nauk, 1995 · PMID 7580986
  96. Twenty years of study on effects of pineal peptide preparation: epithalamin in experimental gerontology and oncology.Annals of the New York Academy of Sciences, 1994 · PMID 8010617
  97. Induction of a prolonged increase in growth hormone (GH) levels by GH-releasing hormoneJ Clin Endocrinol Metab, 1993 · PMID 8421103
  98. Delta sleep-inducing peptide administration does not influence growth hormone and prolactin secretion in normal women.Psychoneuroendocrinology, 1993 · PMID 8475226
  99. [The delta sleep-inducing peptide and its role in modulating epileptic activity].Fiziologicheskii zhurnal imeni I.M. Sechenova, 1993 · PMID 8330074
  100. [The use of peptide preparations of the epiphysis (pineal gland) in oncology: 20 years' experience of research on epithalamin].Voprosy onkologii, 1993 · PMID 7975386