1242 sleep evidence claims,
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Tart cherry juice (240ml twice daily) increases total sleep time by approximately 84 minutes and improves sleep efficiency in older adults with insomnia. The effect is attributed to natural melatonin content and procyanidins.
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All topics →Ambien, Xanax, Lunesta… and the natural stacks people use instead
Side-by-side comparisons for "[drug] + natural alternative" searches.
Trending Evidence
View all →Melatonin reduces sleep onset latency by approximately 7 minutes in adults with primary sleep disorders
A comprehensive meta-analysis of 19 RCTs (1,683 participants) found melatonin reduces sleep latency by ~7 minutes and increases total sleep time by ~8 minutes. Effects are more pronounced in older adults and those with circadian rhythm disruptions.
Low-dose melatonin (0.5mg) effectively shifts circadian rhythm for jet lag, shift work, and delayed sleep phase syndrome
Melatonin is the most potent chronobiotic available. Administered 5 hours before dim-light melatonin onset (DLMO), even low doses (0.5mg) produce a 1-2 hour phase advance. This makes it effective for jet lag, shift work adaptation, and delayed sleep phase syndrome. Timing is more critical than dose.
Glycine reduces sleep latency in human RCTs
Glycine (3g before bed) significantly reduces sleep onset latency and improves subjective sleep quality in healthy adults. Evidence from 3 human RCTs shows consistent effects, with the mechanism involving NMDA receptor modulation and thermoregulation.
Moderate-intensity aerobic exercise (150 min/week) significantly improves sleep quality in adults with chronic insomnia
A 4-week RCT found 150 min/week of moderate aerobic exercise significantly improved PSQI scores and objective sleep measures in adults with chronic insomnia. Exercise is recommended as a first-line behavioral intervention for insomnia.
Glycine improves overall sleep quality and reduces daytime sleepiness
Beyond reducing sleep latency, glycine (3g before bed) improves PSG-measured sleep quality including increased REM sleep and reduced nocturnal awakenings. Daytime sleepiness and fatigue are also significantly reduced the following morning.
Ashwagandha root extract (300mg BID) significantly improves sleep quality and reduces sleep onset latency in adults with insomnia
A well-designed 8-week RCT (n=138) found ashwagandha root extract significantly improved PSQI scores, reduced sleep onset latency, and improved sleep efficiency. Benefits were most pronounced in adults with insomnia and anxiety.
Fresh Evidence
Recently added, highest-rated claims
Milk-derived bioactives and fortified or fermented milk products improve sleep efficiency in randomized controlled trials.
A systematic review and meta-analysis of 11 RCTs found that milk-derived bioactives and fortified or fermented milk products significantly improved sleep efficiency (SMD = 0.45; 95% CI, 0.21-0.70). Subgroup analyses showed greater improvements in sleep efficiency (SMD = 0.52) and wake after sleep onset (MD = -8.24 minutes) in individuals with sleep or health disturbances, and reduced sleep latency in healthy participants (MD = -2.17 minutes).
Moderate physical activity is associated with a modest reduction in insomnia risk, while occupational physical activity may increase insomnia risk
This meta-analysis of 27 observational studies found that moderate physical activity was associated with a 7% lower risk of insomnia (OR=0.93, 95% CI 0.87-1.00), while high physical activity showed no significant association (OR=0.96, 95% CI 0.85-1.09). Occupational physical activity was associated with a 21% higher risk of insomnia (OR=1.21, 95% CI 1.02-1.43). The findings suggest that the intensity and domain of physical activity matter for sleep health.
Nurses' sleep duration and quality have declined significantly over recent decades
A meta-regression of 280 studies involving 219,245 nurses found a significant decline of 28.7 minutes in sleep duration between 1985 and 2022 (95% CI: 26.2, 33.1, ES: 0.43) and a 1.6-point increase in global PSQI scores between 1990 and 2023, indicating poorer sleep quality (95% CI: 1.47, 1.77, ES: 0.49). These trends suggest an increased risk of fatigue, impaired clinical performance, staff burnout, and work-related accidents.
Variable-rate feedback infusion reduces cumulative opioid consumption at 48 hours postoperatively compared with fixed-rate basal infusion in patients undergoing mixed surgery
This protocol describes a prospective, multicentre, randomised, double-blind, controlled trial to compare cumulative opioid consumption at 48 hours postoperatively between variable-rate feedback infusion and fixed-rate basal infusion modes of intravenous patient-controlled analgesia (PCA). The study will enrol 1170 patients undergoing mixed surgery and will measure total cumulative opioid consumption as the primary outcome, with secondary outcomes including pain scores and quality of recovery. The hypothesis is that variable-rate feedback infusion reduces opioid consumption while providing non-inferior analgesia.
LTC-022 (Lactium and L-theanine) improves sleep maintenance and bedtime regularity in adults with sleep discomfort
In a double-blind, placebo-controlled RCT of 40 adults with sleep discomfort, 8 weeks of LTC-022 supplementation did not significantly improve PSQI or ISI scores compared to placebo. However, sleep diary analysis showed significant reductions in wake after sleep onset (WASO) counts and earlier bedtime in the LTC-022 group, along with within-group improvements in total sleep time, sleep onset latency, and sleep efficiency. Gut microbiome analysis revealed increased abundance of Blautia and Ruminococcus genera in the LTC-022 group.
Brief CBT-I improves insomnia symptoms in women receiving chemotherapy for breast cancer
In a randomized clinical trial of 219 women undergoing chemotherapy for breast cancer, 6 weeks of CBT-I significantly reduced insomnia symptoms (ISI score MD, -2.19 [95% CI, -3.33 to -1.05]; P=.002) compared to non-CBT-I groups. However, CBT-I did not significantly improve fatigue symptoms (PROMIS-Fatigue MD, -0.90 [95% CI, -3.08 to 1.28]; P=.52). Bright light therapy (BLT) did not significantly improve either insomnia or fatigue symptoms compared to non-BLT groups.
Evidence Explorer
1000 claimsNocturnal sleep disturbances are associated with the severity of objective excessive daytime sleepiness in children and adolescents with narcolepsy type 1.
In a cross-sectional study of 114 children and adolescents with NT1, those with more severe daytime sleepiness (shorter mean sleep latency on MSLT) had progressively shorter nocturnal sleep latency, higher N1 sleep proportion, lower nocturnal oxygen saturation, and shorter mean REM sleep latency. Generalized linear models identified shorter nocturnal sleep latency, longer N1 sleep duration, higher arousal index, and higher periodic limb movements index as factors associated with shorter MSL.
Longer objective sleep duration is associated with worse cognitive performance in euthymic bipolar disorder
In 40 euthymic individuals with bipolar disorder, longer assumed sleep duration measured by actigraphy was negatively associated with overall cognitive performance (SCIP total score, β = -0.38, p = 0.011), and longer total sleep time was negatively associated with delayed verbal learning (β = -0.48, p = 0.003). Longer sleep onset latency was linked to worse working memory and processing speed, and more wake after sleep onset was linked to worse verbal fluency.
Problematic smartphone use is associated with poor sleep quality and stress in dental students
In a cross-sectional study of 485 dental students, 54.5% were classified as high-risk smartphone users. High-risk users had significantly shorter sleep onset latency (19.90 vs 24.50 min) and higher frequency of poor subjective sleep quality, sleep disturbance, daytime dysfunction, and elevated stress, anxiety, and depression. Stress scores predicted high-risk smartphone use (OR=1.09, 95% CI: 1.02-1.17), while sleep disturbance was a predictor in domain-specific models but lost significance in the fully adjusted model.
Healthy dietary practices, adequate sleep duration, and regular physical activity are associated with lower BMI, body fat percentage, and visceral fat levels in nursing intern students.
In a cross-sectional study of 801 nursing intern students, healthy lifestyle patterns including adequate sleep, regular physical activity, and healthy diet were significantly associated with lower BMI, body fat percentage, and visceral fat. Physical activity showed the strongest inverse association with BMI (r = -0.447, β = -0.389), and the regression model explained 52% of BMI variance (R² = 0.52, F = 48.72, p < 0.001).
Sleep physiology features from digital trackers predict next-day physical fatigue in healthy adults with moderate accuracy
This exploratory study found that sleep tracker-derived features, particularly respiratory rate and REM sleep duration, could predict next-day physical fatigue in healthy adults with an AUC of 0.75. Predictive performance was lower in neurodegenerative disease (AUC=0.62) and immune-mediated inflammatory disease cohorts, indicating limited generalizability to chronic disease populations.
Positional obstructive sleep apnea (POSA) is highly prevalent and characterized by lower BMI and a more favorable sleep and oxygenation profile independent of AHI.
In a retrospective analysis of 12,036 OSA patients, 66.3% had POSA and 27.8% had supine-exclusive POSA. Compared to non-POSA, POSA patients had lower AHI (24.1 vs. 44.4 events/h), lower BMI (29.2 vs. 31.4 kg/m²), and after adjustment for AHI, showed shorter sleep latency, higher sleep efficiency, greater N3 proportion, improved oxygenation, and lower arousal index, with differences more pronounced at lower AHI levels.
Replacing 15 minutes of sleep or sedentary behavior with moving at any intensity reduces the risk of physical activity-related cancer in UK adults.
In a prospective analysis of 59,218 UK Biobank participants, replacing 15 minutes of sleep or sedentary behavior with moving at any intensity was associated with a 2% lower risk of PA-related cancer (HR 0.98, 95%CI 0.97-0.99). Greater moderate-to-vigorous physical activity, particularly vigorous activity, showed the most robust risk reduction.
Sleep disturbances and sleep latency are associated with metabolic syndrome in male Taiwanese workers
In a cross-sectional study of 348 Taiwanese workers, sleep disturbances and sleep latency were significant predictors of metabolic syndrome in men, while shift work and BMI were associated in women. The overall prevalence of metabolic syndrome was 26.4%, with higher rates in men (33.3%) than women (19.3%).
THC/CBD combination reduces RLS severity in patients with multiple sclerosis and idiopathic RLS
In an open-label trial, 2.7 mg THC/2.5 mg CBD significantly improved International Restless Legs Syndrome Rating Scale (IRLS) scores after 1 and 3 months (p < 0.001). Wake after sleep onset (WASO) also significantly decreased (p = 0.015), while sleep latency and sleep efficiency did not change significantly. After 1 year, 66.66% of patients remained on treatment with sustained IRLS improvement (p = 0.000).
Sleep physiology features from wearable trackers predict next-day physical fatigue in healthy adults with moderate discriminative capacity
The study evaluated the feasibility of using consumer- and research-grade sleep trackers to predict next-day fatigue and sleepiness in individuals with neurodegenerative and immune-mediated inflammatory diseases. In healthy adults, machine learning models achieved an AUC of 0.75 for predicting next-day physical fatigue, with respiratory rate and REM sleep duration as key features. Predictive performance was lower in chronic disease cohorts (AUC 0.62 for physical fatigue in NDD).
Frequent forest walking is associated with higher daily happiness, ikigai, and enjoyment of daily life in a Japanese general population
In a cross-sectional study of 3472 Japanese adults, those who went forest walking at least once per month had significantly higher odds of frequent happiness (aOR=1.72), higher degree of happiness (aOR=1.54), having ikigai (aOR=1.65), and enjoying daily life (aOR=2.38) compared to those who rarely forest walked. The findings suggest that occasional forest bathing may be linked to improved well-being and quality of life.
Objective sleep parameters are associated with distinct cognitive domains in euthymic bipolar disorder
In 40 euthymic individuals with bipolar disorder, actigraphy-measured sleep parameters were associated with cognitive performance. Longer assumed sleep duration was negatively associated with overall cognitive score (β = -0.38, p = 0.011), longer sleep onset latency was negatively associated with working memory (β = -0.41, p = 0.014) and processing speed (β = -0.38, p = 0.002), and greater wake after sleep onset was negatively associated with verbal fluency (β = -0.39, p = 0.016).
Newest Studies
All →Comparison of cumulative opioid consumption between variable-rate feedback infusion and fixed-rate basal infusion modes of intravenous patient-controlled analgesia following mixed surgery: protocol for a prospective randomised controlled trial.
BMJ open, 2026 · observational
Five-year patient-reported outcomes of individualized nutrition therapy supporting nutritional ketosis in adults with type 2 diabetes.
Frontiers in nutrition, 2026 · observational
Associations of actigraphic sleep parameters with adipokines in older adults in the Baltimore longitudinal study of aging.
Sleep advances : a journal of the Sleep Research Society, 2026 · observational
The Impact of Milk-Derived Bioactives and Fortified or Fermented Milk Products on Sleep Quality: A Systematic Review and Meta-Analysis.
Nutrition reviews, 2026 · observational
Recently Updated
All →Insomnia induces intestinal microbiota disorder, and artificial interventions targeting gut microbiota can improve sleep.
This narrative review summarizes evidence that insomnia can disrupt intestinal microbiota by activating immune responses, the HPA axis, and neuroendocrine systems, while gut microbiota can exacerbate insomnia via neurotransmitter and inflammatory factor release. Artificial interventions such as probiotics, traditional Chinese medicine, fecal microbiota transplantation, diet, and exercise may improve sleep by affecting neurotransmitter and microbial metabolite release.
Melissa officinalis Phytosome (MOP) improves sleep quality in adults with mild insomnia
In a double-blind, placebo-controlled crossover study, MOP significantly reduced Insomnia Severity Index (ISI) scores by an average of 2.9 points compared to placebo (6.8 ± 4.1 vs 9.7 ± 3.7, p=0.003). Slow-wave sleep (SWS) duration increased by 15%, REM sleep decreased by 10%, and 87% of treated participants reported improved sleep quality versus 30% in the placebo group (χ²=21.01, p=0.0003).
Gut microbiota taxa are causally associated with insomnia risk in European ancestry individuals
A Mendelian randomization study identified that Enterorhabdus, Family XIII AD3011 group, Paraprevotella, and Lachnospiraceae UCG004 increase insomnia risk, while Coprococcus1, Coprobacter, Desulfovibrio, Flavonifractor, Olsenella, Odoribacter, and Oscillibacter decrease risk. For specific insomnia phenotypes, Eisenbergiella increased risk of trouble falling asleep, while Haemophilus and Eubacterium brachy group reduced it; Family XIII UCG001, Lachnospiraceae FCS020 group, and Olsenella increased risk of waking too early, while Eubacterium brachy group and Victivallis reduced it.
Six hub herb pairs (Radix Astragali-Radix et Rhizoma Ginseng, Rhizoma Chuanxiong-Radix Glycyrrhizae, Seman Platycladi-Semen Ziziphi Spinosae, Pericarpium Citri Reticulatae-Radix Glycyrrhizae, Radix Polygalae-Semen Ziziphi Spinosae, Radix Astragali-Semen Ziziphi Spinosae) may treat insomnia via the cAMP signaling pathway synergistically with HIF-1, prolactin, chemical carcinogenesis receptor activation, and PI3K-Akt signaling pathways.
This study analyzed 104 TCM prescriptions for insomnia using data mining, network pharmacology, and molecular docking. Six hub herb pairs were identified, and network pharmacology suggested they may act through the cAMP signaling pathway in synergy with four other pathways, with molecular docking showing good binding affinity between active ingredients and hub targets.
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