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

Updated 7 November 2026
How we grade
30 studies cited

Supplements studied: 4
Medicines and peptides: 3
Graded outcomes: 13

Evidence by supplement

Strong
Moderate
Limited
Very limited

4 supplements

Tryptophan

Tryptophan: outcomes studied for Sleep Quality
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Sleep Latency Doses ≥1g decrease sleep latency; best results in mild insomnia	Improves (the measure goes down)	Moderate effect		800 people
	Subjective Sleepiness Increased rated subjective sleepiness at doses ≥1g	Improves (the measure goes up)	Moderate effect		400 people

Apigenin

Apigenin: outcomes studied for Sleep Quality
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Sleep Quality Small Improvement (chamomile extract studies)	Improves (the measure goes up)	Small effect		120 people
	Daytime Functioning Trend toward improvement, not statistically significant	Improves (the measure goes up)	Small effect		34 people

Magnolia Bark (Magnolia officinalis)

Sleep Quality: improves

Magnolia Bark (Magnolia officinalis): outcomes studied for Sleep Quality
Grade	Outcome	Effect	Size	Studies	People	Studies 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
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Sleep Latency Moderate Decrease - 100mg GABA reduced time to fall asleep	Improves (the measure goes down)	Moderate effect		120 people
	Non-REM Sleep Duration Small Increase in non-REM sleep duration	Improves (the measure goes up)	Small effect		60 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
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Slow-Wave Sleep Duration Enhanced deep sleep duration (GHRH analog data)	Improves (the measure goes up)	Moderate effect	13 studies	35 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
Outcome	Effect	Size	Studies	People
Sleep Onset Latency Moderate Decrease	Improves (the measure goes down)	Moderate effect	12 studies	85 people
Total Sleep Time Moderate Increase	Improves (the measure goes up)	Moderate effect	12 studies	92 people
Delta Wave Activity Moderate Increase	Improves (the measure goes up)	Moderate effect	1 study	45 people

Epitalon

Melatonin Production: improves
Sleep Architecture: improves

Epitalon: outcomes studied for Sleep Quality
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Melatonin Production Moderate increase in nocturnal melatonin	Improves (the measure goes up)	Moderate effect	5 studies	78 people
	Sleep Architecture Small improvement in sleep quality	Improves (the measure goes up)	Small effect	2 studies	42 people

What the published studies found

19 automated readings

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

Ashwagandha: sleep quality
The best available review (2026, 24 studies) found an improvement in sleep quality. That review studied healthy individuals and patients with stress-related or functional disorders. All 9 studies read agree. The evidence is moderate.
9 studies counted of 11 read: 3 reviews and 6 trials (547 people in the trials).
1. Systematic review, 2026; 24 studies; healthy individuals and patients with stress-related or functional disorders: improves (the review the verdict rests on). improved sleep quality, enhancement of cognitive functions Clinical evidence for the adaptogenic effects of Withania somnifera and Rhodiola rosea - A systematic review with molecular interpretation of psychometric outcomesPubMed 41906501
2. Meta-analysis, 2024; 5 studies, 254 people; patients with anxiety and/or insomnia: improves. Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysisPubMed 39083548
3. Meta-analysis, 2021; 5 studies, 400 people; adults 18 years old and above: improves. significant effect on overall sleep (Standardized Mean Difference -0.59 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPubMed 34559859
4. Randomised trial, 2026; 135 people: improves. Sleep quality, psychological well-being, and eating behavior significantly improved from baseline to day 60 in … Efficacy and safety of Ashwagandha root extract sustained-release (AshwaSR) capsules in healthy adult, stressed subjects: A randomized, double-blind, placebo-controlled, parallel-group, 3-arm clinical trialPubMed 41824889
5. Randomised trial, 2026; 66 people; postmenopausal women aged 45-65 years: improves. significantly greater improvements in sleep quality Effects of Withania somnifera root extract on sleep quality, body composition, and menopausal symptoms in postmenopausal women: a randomized, double-blind, placebo-controlled trialPubMed 42742071
6. Randomised trial, 2025; 90 people: improves. improvements in PSS, BAI, and PSQI scores A New Ashwagandha Formulation (Zenroot™) Alleviates Stress and Anxiety Symptoms While Improving Mood and Sleep Quality: A Randomized, Double-Blind, Placebo-Controlled Clinical StudyPubMed 40875185
7. Randomised trial, 2024; 52 people; healthy adults with sleep problems: improves. Changes in the visual analogue scale (VAS) for sleep quality were significantly higher in the … Effectiveness of Enriched Milk with Ashwagandha Extract and Tryptophan for Improving Subjective Sleep Quality in Adults with Sleep Problems: A Randomized Double-Blind Controlled TrialPubMed 39189195
8. Randomised trial, 2022; 60 people; healthy college students: improves. group membership affected final sleep (58.4 ± 12.4 vs. 48.2 ± 15.0 The Impact of Ashwagandha on Stress, Sleep Quality, and Food Cravings in College Students: Quantitative Analysis of a Double-Blind Randomized Control TrialPubMed 35984871
9. Randomised trial, 2020; 144 people; healthy adults with non-restorative sleep: improves. 72% increase in self-reported sleep quality A randomized, double blind, placebo controlled study to evaluate the effects of ashwagandha (Withania somnifera) extract on sleep quality in healthy adultsPubMed 32540634
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Coenzyme Q10: sleep quality
Mixed or unclear: two readings of the studies disagreed. One reading found evidence too weak to tell for sleep quality, the other an improvement. The question is open.
1 study counted of 7 read: 1 trial (50 people in the trials).
1. Randomised trial, 2025; 50 people; patients with tinnitus due to presbycusis: improves. sleep disorder (-7.60 ± 1.38) and (-1.0 ± 8.55) The Effect of Coenzyme Q10 on Tinnitus Severity and Sleep Quality in Patients with PresbycusisPubMed 39850225
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Creatine: sleep quality
The studies read are too weak to tell whether Creatine changes sleep quality. The evidence is very weak.
5 studies counted of 9 read: 4 trials (93 people in the trials).
1. Crossover trial, 2026; 58 people; healthy and active adults: mixed results. Some positive and potentially undesirable effects were observed in sleep quality assessments Effects of six weeks of guanidinoacetic acid supplementation with and without creatine monohydrate on cognitive function and markers of health in healthy adultsPubMed 42730704
2. Study, 2026; tactical populations (e.g. military, law enforcement): improves. The emerging and evolving evidence supporting creatine as an ergogenic aid: history and applicationsPubMed 41870601
3. Crossover trial, 2025; 14 people; physically active men: improves. CrM improved sleep quality compared to PL Effects of Creatine Monohydrate Loading on Sleep Metrics, Physical Performance, Cognitive Function, and Recovery in Physically Active Men: A Randomized, Double-Blind, Placebo-Controlled, Crossover TrialPubMed 41470776
4. Randomised trial, 2024; 21 people; naturally menstruating females: no clear difference. Creatine Improves Total Sleep Duration Following Resistance Training Days versus Non-Resistance Training Days among Naturally Menstruating FemalesPubMed 39203908
5. Randomised trial, 2013: no clear difference. no general changes were observed in Creatine supplementation in fibromyalgia: a randomized, double-blind, placebo-controlled trialPubMed 23554283
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Ginkgo Biloba: sleep quality
The 1 study read (398 people in all) mostly found an improvement in sleep quality. The evidence is limited.
1 study counted of 11 read: 1 trial (398 people in the trials).
1. Randomised trial, 2026; 398 people; children aged 5-14 with monosymptomatic nocturnal enuresis: improves. Ginkgo biloba versus desmopressin in treatment of children with monosymptomatic nocturnal enuresis: A randomized controlled trialPubMed 42321081
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Glycine: sleep quality
The studies read are too weak to tell whether Glycine changes sleep quality. They lean toward an improvement, which is not enough to claim one. The evidence is very weak.
1 study counted of 9 read: 1 trial (20 people in the trials).
1. Crossover trial, 2021; 20 people; urology outpatients with overactive bladder symptoms: improves. sleep latency, latency to first nighttime urination Dietary glycine improves urine storage symptoms in urology outpatientsPubMed 33793143
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Inositol: sleep quality
The studies read are too weak to tell whether Inositol changes sleep quality. They lean toward an improvement, which is not enough to claim one. The evidence is very weak.
1 study counted of 4 read: 1 trial (60 people in the trials).
1. Randomised trial, 2022; 60 people; pregnant women with low-risk singleton pregnancies: improves. mean difference of the total sleep quality score between the two groups was -1.537 The impact of myo-inositol supplementation on sleep quality in pregnant women: a randomized, double-blind, placebo-controlled studyPubMed 32933356
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Lavender: sleep quality
The studies disagree. A Cochrane review (2020, 13 studies, 708 people) found little or no difference in sleep quality, while 10 of the 11 studies read found an improvement. The evidence is very weak.
11 studies counted of 11 read: 8 reviews and 3 trials (153 people in the trials).
1. Meta-analysis, 2020; 13 studies, 708 people; people with dementia in institutional care: no clear difference (the review the verdict rests on). We did not find evidence of benefit on these outcomes. Aromatherapy for dementiaPubMed 32813272
2. Meta-analysis, 2025; 11 studies, 628 people: improves. sleep-enhancing effect of lavender essential oil intervention in adults was significant The Sleep-Enhancing Effect of Lavender Essential Oil in Adults: A Systematic Review and Meta-AnalysisPubMed 40600743
3. Meta-analysis, 2025; 9 studies; older adults with sleep disorders: improves. significant improvement in the total score of sleep quality A systematic review and meta-analysis of clinical trials on lavender for sleep disorders in older adultsPubMed 41057090
4. Meta-analysis, 2023; 3 studies; postpartum mothers: improves. sleep quality in the group receiving lavender improved The effect of lavender on mothers sleep quality in the postpartum period: a systematic review and meta-analysisPubMed 35080353
5. Systematic review, 2022; 13 studies, 838 people; patients with cancer: improves. lavender was significantly effective in the reduction of anxiety and pain, and improved sleep quality A systematic review of the effect of lavender on cancer complicationsPubMed 35462027
6. Systematic review, 2022; 20 studies; adults without insomnia: improves. Lavender essential oil was associated with improved sleep quality The Effect of Lavender on Sleep Quality in Individuals Without Insomnia: A Systematic ReviewPubMed 35708558
7. Meta-analysis, 2022; 4 studies; prenatal and postnatal women: improves. produced a 0.98-point improvement in postnatal mothers' quality of sleep [Fatigue relief by aromatherapy use in prenatal and postnatal women: a systematic review and meta-analysis]PubMed 36312866
8. Systematic review, 2019; 3 studies; menopausal and elderly women: improves. Effect of Lavender on Sleep, Sexual Desire, Vasomotor, Psychological and Physical Symptom among Menopausal and Elderly Women: A Systematic ReviewPubMed 31497578
9. Randomised trial, 2026; 90 people; elderly individuals: improves. PSQI total score was 6.11±2.86 in the pre-test and 4.33±2.07 in the post-test The effect of lavender scent recommended to the elderly on sleep quality and physical balance: A randomized controlled trialPubMed 42623910
10. Randomised trial, 2024; 54 people: improves. Sleep quality scores significantly increased (p = <0.001) The effect of lavender and bergamot oil applied via inhalation on the anxiety level and sleep quality of surgical intensive care unit patientsPubMed 38490827
11. Randomised trial, 2021; 9 people: improves. All participants reported better sleep quality A pilot study on essential oil aroma stimulation for enhancing slow-wave EEG in sleeping brainPubMed 33441798
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Lemon Balm: sleep quality
The best available review (2024) found an improvement in sleep quality. That review studied people with psychological well-being concerns. 2 of the 3 studies read agree; 1 found no clear difference. The evidence is limited.
3 studies counted of 11 read: 1 review and 2 trials (44 people in the trials).
1. Systematic review, 2024; people with psychological well-being concerns: improves (the review the verdict rests on). can elicit cognitive and sleep-quality enhancement Clinical Efficacy and Tolerability of Lemon Balm (Melissa officinalis L.) in Psychological Well-Being: A ReviewPubMed 39458539
2. Crossover trial, 2024: improves. significant reduction in the ISI score in the treated group Effects of Melissa officinalis Phytosome on Sleep Quality: Results of a Prospective, Double-Blind, Placebo-Controlled, and Cross-Over StudyPubMed 39683592
3. Randomised trial, 2023; 44 people; type 2 diabetes patients with depression: no clear difference. no significant differences were observed in The effects of melissa officinalis on depression and anxiety in type 2 diabetes patients with depression: a randomized double-blinded placebo-controlled clinical trialPubMed 37131158
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Magnesium: sleep quality
The studies disagree. The best available review (2026, 12 studies) found little or no difference in sleep quality, while 4 of the 5 studies read found an improvement. The evidence is very weak.
5 studies counted of 10 read: 3 reviews and 2 trials (155 people in the trials).
1. Systematic review, 2026; 12 studies; adults with sleep-related outcomes: no clear difference (the review the verdict rests on). Findings were inconsistent across subjective outcomes Magnesium Supplementation for Sleep in Adults: A Systematic Review of Randomized Controlled TrialsPubMed 42661485
2. Systematic review, 2024; 15 studies; patients with anxiety or sleep disorders: improves. Five out of eight sleep-related studies reported improvements in sleep parameters Examining the Effects of Supplemental Magnesium on Self-Reported Anxiety and Sleep Quality: A Systematic ReviewPubMed 38817505
3. Meta-analysis, 2021; 3 studies, 151 people; older adults with insomnia: improves. sleep onset latency time was 17.36 min less Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-AnalysisPubMed 33865376
4. Randomised trial, 2024; 80 people; adults with self-reported sleep problems: improves. MgT significantly (p < 0.05) improved vs placebo deep sleep score Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trialPubMed 39252819
5. Randomised trial, 2022; 75 people; patients with restless legs syndrome: improves. Therapeutic effects of magnesium and vitamin B6 in alleviating the symptoms of restless legs syndrome: a randomized controlled clinical trialPubMed 36587225
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Melatonin: sleep quality
The studies disagree. A Cochrane review (2018, 4 studies, 151 people) did not settle it for sleep quality, while 3 of the 8 studies read found an improvement. The evidence is very weak.
Side effects: 1 of the 7 studies that reported on them found more with Melatonin (headaches, gastrointestinal problems, dizziness).
8 studies counted of 11 read: 7 reviews and 1 trial (57 people in the trials).
1. Systematic review, 2018; 4 studies, 151 people; adults in the intensive care unit: unclear: evidence too weak to tell (the review the verdict rests on). Melatonin for the promotion of sleep in adults in the intensive care unitPubMed 29746721
2. Systematic review, 2026; 98 studies, 28,920 people; individuals with chronic non-cancer pain: improves. melatonin significantly improved sleep quality compared with placebo Comparative effectiveness and safety of pharmacological interventions for sleep outcomes in chronic non-cancer pain: a systematic review and network meta-analysisPubMed 42430948
3. Meta-analysis, 2026; 23 studies, 2,028 people; people with chronic or postoperative musculoskeletal pain: mixed results. Sleep quality favoured melatonin in people with chronic MSK pain Efficacy and effectiveness of melatonin for the management of musculoskeletal pain: a systematic review and meta-analysis of placebo and active controlled trialsPubMed 42378431
4. Systematic review, 2026; 23 studies, 1,941 people; adults with migraine and sleep disturbances: no clear difference. Interventions for Migraine and Sleep: A Systematic Review Exploring Their Bidirectional AssociationPubMed 41874004
5. Systematic review, 2026; 7 studies, 497 people; menopausal women: no clear difference. A systematic review and meta-analysis of randomized controlled trials investigated the effects of melatonin supplementation on bone mineral density, quality of life, and sleep in menopausal womenPubMed 41693954
6. Meta-analysis, 2026; 4 studies, 455 people; patients undergoing total joint arthroplasty: no clear difference. melatonin did not significantly impact subjective or objective sleep outcomes Evaluating Whether Melatonin Impacts Postoperative Sleep Following Total Joint Arthroplasty: A Systematic Review and Meta-analysis of Randomized Controlled TrialsPubMed 42205627
7. Meta-analysis, 2026; 7 studies, 409 people: improves. The Effectiveness of Melatonin for Sleep Disturbances in Parkinson' Disease: Systematic Review and Meta-AnalysisPubMed 40588412
8. Randomised trial, 2026; 57 people; patients undergoing urological surgery: improves. sleep-quality scores increased significantly in the melatonin group The effect of preoperative melatonin patches on sleep quality in patients undergoing urological surgeryPubMed 42138936
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Omega-3 Fatty Acids: sleep quality
The studies disagree. The best available review (2024, 8 studies) found an improvement in sleep quality, while 3 of the 8 studies read found no clear difference. The evidence is very weak.
8 studies counted of 11 read: 4 reviews and 4 trials (202 people in the trials).
1. Meta-analysis, 2024; 8 studies: improves (the review the verdict rests on). Subjectively assessed sleep was significantly improved by omega-3 LC-PUFA Effect of omega-3 fatty acids on sleep: a systematic review and meta-analysis of randomized controlled trialsPubMed 39583980
2. Systematic review, 2023; 9 studies; postmenopausal women: no clear difference. sleep quality outcomes displayed heterogeneity across the studies Effects of Omega-3 Polyunsaturated Fatty Acids Intake on Vasomotor Symptoms, Sleep Quality and Depression in Postmenopausal Women: A Systematic ReviewPubMed 37836515
3. Meta-analysis, 2021; 20 studies; infants, children, and adults: no clear difference. No effectiveness was found in adults' total sleep duration, sleep latency, sleep efficiency, sleep quality Omega-3 long-chain polyunsaturated fatty acid and sleep: a systematic review and meta-analysis of randomized controlled trials and longitudinal studiesPubMed 33382879
4. Meta-analysis, 2018; 3 studies, 483 people; menopausal women experiencing vasomotor symptoms: no clear difference. Meta-analysis of the data showed no difference in the frequency and severity of hot flushes, … Effect of omega-3 supplements on vasomotor symptoms in menopausal women: A systematic review and meta-analysisPubMed 30056356
5. Randomised trial, 2025; patients with type 2 diabetes: improves. fish oil supplementation enhances sleep parameters Marine n-3 polyunsaturated fatty acids slow sleep impairment progression by regulating central circadian rhythms in type 2 diabetesPubMed 40347940
6. Randomised trial, 2022; 66 people; healthy Japanese males and females aged 45 years or older: improves. factor III (frequent dreaming) scores among the OSA-MA scores were significantly improved Effect of Docosahexaenoic Acid and Eicosapentaenoic Acid Supplementation on Sleep Quality in Healthy Subjects: A Randomized, Double-Blinded, Placebo-Controlled TrialPubMed 36235788
7. Randomised trial, 2021; 84 people; healthy young adults, low oily fish intake: improves. improvements in actigraphy sleep efficiency (p = 0.030) Differential Effects of DHA- and EPA-Rich Oils on Sleep in Healthy Young Adults: A Randomized Controlled TrialPubMed 33467135
8. Crossover trial, 2020; 52 people; hemodialysis patients with uremic pruritus: improves. sleep quality scores were different in two groups The effects of omega-3 on the sleep quality of patients with uremic pruritus undergoing hemodialysis: a randomized crossover studyPubMed 32427120
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Panax Ginseng (Korean Ginseng): sleep quality
The studies read are too weak to tell whether Panax Ginseng (Korean Ginseng) changes sleep quality. The evidence is very weak.
3 studies counted of 8 read: 3 trials (103 people in the trials).
1. Randomised trial, 2020; 50 people: no clear difference. no significant differences in the secondary outcome measurements Efficacy of Korean red ginseng (Panax ginseng) for middle-aged and moderate level of chronic fatigue patients: A randomized, double-blind, placebo-controlled trialPubMed 31987248
2. Randomised trial, 2013; 38 people; patients with fibromyalgia: no clear difference. improvement in sleep (p < .001) Effects of Panax ginseng extract in patients with fibromyalgia: a 12-week, randomized, double-blind, placebo-controlled trialPubMed 23567596
3. Crossover trial, 2013; 15 people; young male healthy volunteers: improves. Total wake time (TWT) was significantly reduced (P<0.05) and SE was increased (P<0.05), although slow … Effects of red ginseng extract on sleeping behaviors in human volunteersPubMed 23872254
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Probiotics: sleep quality
The best available review (2025, 6 studies, 424 people) found an improvement in sleep quality. That review studied patients with insomnia. 7 of the 8 studies read agree; 1 found no clear answer. The evidence is moderate.
8 studies counted of 11 read: 7 reviews and 1 trial.
1. Systematic review, 2025; 6 studies, 424 people; patients with insomnia: improves (the review the verdict rests on). significant reduction in Pittsburgh Sleep Quality Index (PSQI) Impact of probiotics on sleep quality and mood states in patients with insomnia: a systematic review and meta-analysisPubMed 40740336
2. Systematic review, 2026; 13 studies, 890 people; adults, healthy and poor sleep quality: improves. probiotic supplementation significantly reduced PSQI scores Association between probiotic intervention and sleep quality in the general adult population: a systematic review and meta-analysisPubMed 41958906
3. Systematic review, 2026; 19 studies, 762 people: improves. Overall, probiotic intake appears to modify resting state connectivity and activity, decrease involvement of several … The effects of oral probiotic intervention on brain structure and function in human adults: a systematic reviewPubMed 41501074
4. Meta-analysis, 2024; 15 studies: improves. PSQI) scores in the probiotics group was significantly lower Effects of probiotics on sleep parameters: A systematic review and meta-analysisPubMed 39094854
5. Systematic review, 2024; 11 studies; adults with sleep disorders or sub-healthy sleep conditions: improves. improves sleep states to some extent Effect of probiotics and paraprobiotics on patients with sleep disorders and sub-healthy sleep conditions: a meta-analysis of randomized controlled trialsPubMed 39479010
6. Meta-analysis, 2023; 18 studies: unclear: evidence too weak to tell. not demonstrated to be associated with significant improvement in sleep quality Effect of gut microbiota modulation on sleep: a systematic review and meta-analysis of clinical trialsPubMed 37023468
7. Meta-analysis, 2023; people with sleep disturbances: improves. probiotics supplementation significantly reduced the self-assessed parameter Microbiota Composition and Probiotics Supplementations on Sleep Quality-A Systematic Review and Meta-AnalysisPubMed 38131749
8. Randomised trial, 2024; healthy adults under mild stress aged 18-35 years: improves. exhibited significant improvements in wearable device- measured sleep duration Lacticaseibacillus paracasei 207-27 alters the microbiota-gut-brain axis to improve wearable device-measured sleep duration in healthy adults: a randomized, double-blind, placebo-controlled trialPubMed 39385735
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Rhodiola Rosea: sleep quality
The best available review (2026, 5 studies) found an improvement in sleep quality. That review studied healthy individuals and patients with stress-related or functional disorders. All 2 studies read agree. The evidence is moderate.
2 studies counted of 6 read: 1 review and 1 trial (24 people in the trials).
1. Systematic review, 2026; 5 studies; healthy individuals and patients with stress-related or functional disorders: improves (the review the verdict rests on). improved sleep quality, enhancement of cognitive functions Clinical evidence for the adaptogenic effects of Withania somnifera and Rhodiola rosea - A systematic review with molecular interpretation of psychometric outcomesPubMed 41906501
2. Randomised trial, 2002; 24 people; men living at high altitude: improves. improving the sleep quality in young men [The effect of rhodiola and acetazolamide on the sleep architecture and blood oxygen saturation in men living at high altitude]PubMed 12423559
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Saffron: sleep quality
The studies disagree. The best available review (2022, 8 studies, 431 people) did not settle it for sleep quality, while 10 of the 11 studies read found an improvement. The evidence is very weak.
11 studies counted of 11 read: 5 reviews and 6 trials (534 people in the trials).
1. Meta-analysis, 2022; 8 studies, 431 people; people with insomnia: unclear: evidence too weak to tell (the review the verdict rests on). increased sleep quality (SMD 0.89, 95% CI 0.10 to 1.68 Crocus Sativus for Insomnia: A Systematic Review and Meta-AnalysisPubMed 36141931
2. Meta-analysis, 2025; 11 studies, 637 people; individuals with obesity: improves. saffron supplementation (OR = 11.10, P = 0.000) Nutritional interventions and sleep quality in obese individuals: a systematic review and meta-analysis of randomized control trialsPubMed 41120739
3. Meta-analysis, 2024; 46 studies: improves. sleep disorders of -1.91 (95% CI: -2.88, -0.93) New horizons for the study of saffron (Crocus sativus L.) and its active ingredients in the management of neurological and psychiatric disorders: A systematic review of clinical evidence and mechanismsPubMed 38424688
4. Meta-analysis, 2022; healthy adults, insomnia, type 2 diabetes, methadone maintenance: improves. notable treatment effect on PSQI (MD: -2.14 Effects of saffron supplementation on improving sleep quality: a meta-analysis of randomized controlled trialsPubMed 35325766
5. Meta-analysis, 2020; 21 studies: improves. The effects of saffron (Crocus sativus L.) on mental health parameters and C-reactive protein: A meta-analysis of randomized clinical trialsPubMed 31987241
6. Randomised trial, 2026; 76 people; adults with pulmonary sarcoidosis and sleep disturbances: improves. Compared with the control group, saffron supplementation significantly improved PSQI (adjusted mean difference [MD], -2.21) Efficacy of a Saffron-Based (Crocus sativus L.) Herbal Supplement on Sleep Disturbances in Pulmonary Sarcoidosis: A Randomized Single-Blind Controlled TrialPubMed 42483079
7. Randomised trial, 2025; 165 people; adults with moderate insomnia: improves. sleep quality (SQS) improved significantly after 3 weeks Effect of a saffron extract on sleep quality in adults with moderate insomnia: A decentralized, randomized, double-blind, placebo-controlled trialPubMed 40698027
8. Randomised trial, 2025; 52 people; older adults with sleep complaints: improves. significantly improved subjective sleep quality (p = 0.02) A standardised saffron extract improves subjective and objective sleep quality in healthy older adults with sleep complaints: results from the gut-sleep-brain axis randomised, double-blind, placebo-controlled pilot studyPubMed 40762630
9. Randomised trial, 2021; 120 people; adults with unsatisfactory sleep: improves. greater improvements in sleep quality ratings An investigation into an evening intake of a saffron extract (affron®) on sleep quality, cortisol, and melatonin concentrations in adults with poor sleep: a randomised, double-blind, placebo-controlled, multi-dose studyPubMed 34438361
10. Randomised trial, 2021; 66 people: improves. improved sleep quality, sleep latency, sleep duration, and global scores Effects of Saffron Extract on Sleep Quality: A Randomized Double-Blind Controlled Clinical TrialPubMed 33925432
11. Randomised trial, 2020; 55 people; healthy adults with self-reported sleep problems: improves. saffron was associated with greater improvements in ISI total score Effects of saffron on sleep quality in healthy adults with self-reported poor sleep: a randomized, double-blind, placebo-controlled trialPubMed 32056539
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Tart Cherry Juice: sleep quality
The studies read are too weak to tell whether Tart Cherry Juice changes sleep quality. The strongest review read studied elderly patients with insomnia. The evidence is very weak.
5 studies counted of 8 read: 1 review and 4 trials (91 people in the trials).
1. Systematic review, 2020; 53 studies, 6,832 people; elderly patients with insomnia: unclear: evidence too weak to tell (the review the verdict rests on). Efficacy, acceptability, and tolerability of all available treatments for insomnia in the elderly: a systematic review and network meta-analysisPubMed 32521042
2. Randomised trial, 2026; 44 people; healthy adults: no clear difference. no significant differences in sleep time or quality Montmorency tart cherry supplementation does not impact sleep, body composition, cellular health, or blood pressure in healthy adultsPubMed 35790450
3. Randomised trial, 2022; 19 people; elite female field hockey players: mixed results. significant interaction effects with regards to the total time in bed Effects of Short-Term Intake of Montmorency Tart Cherry Juice on Sleep Quality after Intermittent Exercise in Elite Female Field Hockey Players: A Randomized Controlled TrialPubMed 36011907
4. Crossover trial, 2018; 8 people; elderly adults with insomnia: improves. increased sleep time by 84 minutes on polysomnography Pilot Study of the Tart Cherry Juice for the Treatment of Insomnia and Investigation of MechanismsPubMed 28901958
5. Crossover trial, 2012; 20 people; healthy adults: improves. significant increases in time in bed, total sleep time and sleep efficiency total Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep qualityPubMed 22038497
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Theanine: sleep quality
The best available review (2026, 13 studies, 550 people) found an improvement in sleep quality. 4 of the 6 studies read agree; 1 found no clear difference, 1 found a worse result. The evidence is moderate.
Possible harm: 1 study read reported a worse result for sleep quality with Theanine. One abstract says: "all, except atomoxetine, affected sleep quality, such as by reducing total rapid eye movement (REM), non-REM phase, slow-wave sleep time, and longer sleep-onset latency" Check the studies below, and ask a doctor or pharmacist if this applies to you.
6 studies counted of 11 read: 4 reviews and 2 trials (30 people in the trials).
1. Systematic review, 2026; 13 studies, 550 people: improves (the review the verdict rests on). beneficial effects were reported on both objective and participant-reported outcomes Examining the effect of L-theanine on sleep: a systematic review of dietary supplementation trialsPubMed 41176609
2. Systematic review, 2026; healthy adults: improves. can support sleep quality, with little effect Effects of L-theanine on cognition, mood and sleep: evidence from human trialsPubMed 42761839
3. Meta-analysis, 2025; 18 studies, 897 people; humans of all ages and health status: improves. The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysisPubMed 40056718
4. Systematic review, 2023; children with attention deficit hyperactivity disorder: worsens. affected sleep quality, such as by reducing total rapid eye movement Association between sleep pattern and pharmacological treatment in children with attention deficit disorder with hyperactivity: a systematic reviewPubMed 37255110
5. Crossover trial, 2023; healthy young women: no clear difference. no difference was observed between the theanine Theanine maintains sleep quality in healthy young women by suppressing the increase in caffeine-induced wakefulness after sleep onsetPubMed 37458751
6. Crossover trial, 2019; 30 people; healthy adults without major psychiatric illness: improves. Pittsburgh Sleep Quality Index (PSQI) scores decreased after L-theanine administration Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled TrialPubMed 31623400
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Valerian: sleep quality
The best available review (2024, 8 studies) found an improvement in sleep quality. That review studied adults with insomnia. 6 of the 9 studies read agree; 3 found no clear difference. The evidence is moderate.
9 studies counted of 11 read: 4 reviews and 5 trials (297 people in the trials).
1. Systematic review, 2024; 8 studies; adults with insomnia: improves (the review the verdict rests on). effective concerning subjective improvement of sleep quality Does valerian work for insomnia? An umbrella review of the evidencePubMed 38359657
2. Meta-analysis, 2020; 10 studies, 1,065 people; people with sleep problems: improves. effectiveness to improve subjective sleep quality Valerian Root in Treating Sleep Problems and Associated Disorders-A Systematic Review and Meta-AnalysisPubMed 33086877
3. Systematic review, 2007; 37 studies; healthy individuals and persons with sleep disturbance or insomnia: no clear difference. found no significant differences between valerian and placebo A systematic review of valerian as a sleep aid: safe but not effectivePubMed 17517355
4. Meta-analysis, 2006; 16 studies, 1,093 people; patients with insomnia: improves. statistically significant benefit (relative risk of improved sleep = 1.8 Valerian for sleep: a systematic review and meta-analysisPubMed 17145239
5. Crossover trial, 2021; 39 people: improves. reduction was significantly higher in group A compared to group B The Effects of Valerian on Sleep Quality, Depression, and State Anxiety in Hemodialysis Patients: A Randomized, Double-blind, Crossover Clinical TrialPubMed 33936782
6. Randomised trial, 2011; 100 people; postmenopausal women experiencing insomnia: improves. statistically significant change was reported in the quality of sleep Effect of valerian on sleep quality in postmenopausal women: a randomized placebo-controlled clinical trialPubMed 21775910
7. Crossover trial, 2009; 16 people; older women with insomnia: no clear difference. no statistically significant differences between valerian and placebo A randomized clinical trial of valerian fails to improve self-reported, polysomnographic, and actigraphic sleep in older women with insomniaPubMed 18482867
8. Randomised trial, 1994; 14 people; elderly poor sleepers: no clear difference. The effect of valerian extract on sleep polygraphy in poor sleepers: a pilot studyPubMed 7972346
9. Crossover trial, 1982; 128 people; 128 people tested sleep measures: improves. Aqueous extract of valerian root (Valeriana officinalis L.) improves sleep quality in manPubMed 7122669
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Vitamin D: sleep quality
The best available review (2022, 19 studies) found an improvement in sleep quality. 7 of the 8 studies read agree; 1 found a worse result. The evidence is moderate.
Possible harm: 1 study read reported a worse result for sleep quality with Vitamin D. One abstract says: "overall worse sleep quality (ptrend<0.01). Women who became vitamin D replete (≥32ng/mL) also showed a deterioration in total PSQI sleep quality score" Check the studies below, and ask a doctor or pharmacist if this applies to you.
8 studies counted of 10 read: 5 reviews and 3 trials (301 people in the trials).
1. Meta-analysis, 2022; 19 studies: improves (the review the verdict rests on). statistically significant decrease in the Pittsburgh Sleep Quality Index Vitamin D Supplementation and Sleep: A Systematic Review and Meta-Analysis of Intervention StudiesPubMed 35268051
2. Meta-analysis, 2022; 31 studies: improves. Efficacy of dietary supplements on improving sleep quality: a systematic review and meta-analysisPubMed 33441476
3. Meta-analysis, 2022; 5 studies; people with poor sleep quality: improves. significantly improves sleep quality (MD: -1.32; 95%CI: -2.55 to -0.09; P = 0.04) The effect of vitamin D on sleep quality: A systematic review and meta-analysisPubMed 35578558
4. Meta-analysis, 2020; people with sleep disorders: improves. A meta-analysis: Does vitamin D play a promising role in sleep disorders?PubMed 33133571
5. Meta-analysis, 2019; 2 studies; patients with psychiatric disorders: improves. The effects of vitamin D supplementation on mental health, and biomarkers of inflammation and oxidative stress in patients with psychiatric disorders: A systematic review and meta-analysis of randomized controlled trialsPubMed 31095994
6. Randomised trial, 2024; 212 people; chinese individuals with prediabetes: improves. total PSQI score in vitamin D + calcium group was lower Effects of vitamin D and/or calcium intervention on sleep quality in individuals with prediabetes: a post hoc analysis of a randomized controlled trialPubMed 38366270
7. Randomised trial, 2018; 89 people; 20-50 year-old people with sleep disorders: improves. sleep score (PSQI) reduced significantly in vitamin recipients The effect of vitamin D supplement on the score and quality of sleep in 20-50 year-old people with sleep disorders compared with control groupPubMed 28475473
8. Randomised trial, 2016; overweight postmenopausal women with low vitamin D: worsens. deterioration in total PSQI sleep quality score Repletion of vitamin D associated with deterioration of sleep quality among postmenopausal womenPubMed 27687537
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.

Key findings

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

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Studies cited

30 studies from PubMed

Overview of Epitalon-Highly Bioactive Pineal Tetrapeptide with Promising PropertiesInt J Mol Sci, 2025 · PMID 40141333
Normalizing effect of the pineal gland peptides on the daily melatonin rhythm in old monkeys and elderly peopleAdv Gerontol, 2007 · PMID 17969590
Delta sleep-inducing peptide (DSIP): a still unresolved riddleJ Neurochem, 2006 · PMID 16539679
Pineal peptides restore the age-related disturbances in hormonal functions of the pineal gland and the pancreasExp Gerontol, 2005 · PMID 15664732
Effect of peptide preparation epithalamin on circadian rhythm of epiphyseal melatonin-producing function in elderly peopleBull Exp Biol Med, 2004 · PMID 15452611
Delta sleep inducing peptide (DSIP): effect on respiration activity in rat brain mitochondria and stress protective potency under experimental hypoxiaPeptides, 2003 · PMID 12668217
Aging of the pineal glandUsp Fiziol Nauk, 2002 · PMID 12096440
Opioid detoxification with delta sleep-inducing peptide: results of an open clinical trialJ Clin Psychopharmacol, 1998 · PMID 9617990
Delta-sleep-inducing peptide sequels in the mechanisms of resistance to emotional stressAnn N Y Acad Sci, 1995 · PMID 8597403
Effects of delta sleep-inducing peptide on sleep of chronic insomniac patients. A double-blind studyNeuropsychobiology, 1992 · PMID 1299794
DSIP--a tool for investigating the sleep onset mechanism: a review.The International journal of neuroscience, 1988 · PMID 3286557
Delta sleep-inducing peptide modulates the stimulation of rat pineal N-acetyltransferase activity by involving the alpha 1-adrenergic receptorJ Neurochem, 1987 · PMID 3029331
Therapeutic effects of delta-sleep-inducing peptide (DSIP) in patients with chronic, pronounced pain episodes. A clinical pilot studyEur Neurol, 1984 · PMID 6548970
A clinical trial with DSIPEur Neurol, 1984 · PMID 6391926
Delta-sleep-inducing peptide (DSIP): a reviewNeurosci Biobehav Rev, 1984 · PMID 6145137
Successful treatment of withdrawal symptoms with delta sleep-inducing peptide, a neuropeptide with potential agonistic activity on opiate receptorsNeuropsychobiology, 1983 · PMID 6328354
Acute and delayed effects of DSIP (delta sleep-inducing peptide) on human sleep behaviorInt J Clin Pharmacol Ther Toxicol, 1981 · PMID 6895513
Clinical interventions with various agents to prevent early childhood caries: A systematic review with network meta-analysis.Int J Paediatr Dent · PMID 36718540
Fluorides for preventing early tooth decay (demineralised lesions) during fixed brace treatment.Cochrane Database Syst Rev · PMID 31742669
Screening and Interventions to Prevent Dental Caries in Children Younger Than 5 Years: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.JAMA · PMID 34874413
Fluoride toothpastes of different concentrations for preventing dental caries.Cochrane Database Syst Rev · PMID 30829399
Comparative study of Kefir yogurt-drink and sodium fluoride mouth rinse on salivary mutans streptococciJ Contemp Dent Pract · PMID 25095846
Effects of probiotics on salivary Streptecoccus mutans and Lactobacillus levels in orthodontic patientsAm J Orthod Dentofacial Orthop · PMID 30268262
The effect of systemic zinc supplementation on oral health in low socioeconomic level childrenTurk J Pediatr · PMID 20112596
A clinical investigation to evaluate reduction in dental stain provided by the once-daily use of a breath mint or chewing gumCompend Contin Educ Dent · PMID 11913308
Effects of a Baking Soda Gum on extrinsic dental stain: results of a longitudinal 4-week assessmentCompend Contin Educ Dent · PMID 11913306
Efficacy of baking soda-containing chewing gum in removing natural tooth stainCompend Contin Educ Dent · PMID 11913307
Effects of passiflora incarnata and midazolam for control of anxiety in patients undergoing dental extraction.Med Oral Patol Oral Cir Bucal · PMID 27918731
Herbal medicines as anxiolytics prior to third molar surgical extraction. A randomized controlled clinical trial.Clin Oral Investig · PMID 32951121
Effect of a sugar-free chewing gum containing magnolia bark extract on different variables related to caries and gingivitis: a randomized controlled intervention trialCaries Res · PMID 21822018