1231 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
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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
Physical exercise training may increase cardiorespiratory fitness in people with spinal cord injury
This systematic review of 17 randomized controlled trials (505 participants) found that physical exercise training may increase cardiorespiratory fitness (CRF) in people with spinal cord injury (SCI), with a standardized mean difference of 0.48 (95% CI 0.18 to 0.77) compared to no intervention. However, the certainty of evidence is low due to high risk of bias in most studies, and effects on other outcomes (functional fitness, quality of life, depression, anxiety, adverse events) are very unclear.
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.
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.
Benralizumab reduces cough and/or dyspnea frequency and improves cough-specific health-related quality of life in patients with severe eosinophilic asthma in Asia
In a post-hoc analysis of the MIRACLE trial, benralizumab significantly increased the proportion of patients transitioning from frequent to non-frequent cough at Week 8 (54.0% vs 39.7%, p=0.0051) and improved cough-related SGRQ items earlier than placebo, with sustained benefits through Week 48. Similar improvements were seen for dyspnea frequency at Week 8 (64.2% vs 47.1%, p=0.0026) and Week 48 (75.5% vs 63.4%, p=0.0221). Benefits were more pronounced in patients with baseline blood eosinophil counts ≥300 cells/μL.
Evidence Explorer
662 claimsMuscular endurance and strength are lower in lymphangioleiomyomatosis (LAM) patients compared to matched healthy controls, coincident with greater self-reported fatigue.
In a cross-sectional study of 15 LAM patients and 15 matched controls, LAM patients exhibited significantly lower muscular force (by 220±89 N), power (by 312±129 W), endurance (by 4674±1974 N*sec), and worse fatigue survey scores (p=0.02 to 0.0004). Poorer muscular endurance in LAM was associated with shorter 6-minute walk distance (r=0.68), lower VO2max (r=0.58), and worse fatigue (r=0.56). No differences in fiber type distribution were found.
Low-sodium oxybate reduces excessive daytime sleepiness and improves nighttime sleep quality in participants with narcolepsy
In a phase 4 open-label study of 34 participants with narcolepsy (NT1 or NT2), low-sodium oxybate (LXB) significantly reduced daytime sleepiness, with a least-squares mean change in Epworth Sleepiness Scale score of -7.7 (SE 0.9, P<0.0001). LXB also decreased transitions to lighter sleep stages by 13.1 (SE 2.9, P<0.0001), increased N3 (deep sleep) duration by 45.0 minutes (SE 8.8, P<0.0001), and reduced nocturnal awakenings by 3.2 (SE 0.9, P=0.0013). Most participants reported improved sleep quality and overall disease severity.
Preoperative vitamin D deficiency is associated with a substantially increased risk of postoperative delirium in pediatric patients undergoing general anesthesia for laparoscopic surgery
In a single-center retrospective study of 320 pediatric patients undergoing laparoscopic surgery under general anesthesia, the incidence of postoperative delirium (POD) was 80.3% (257/320) based on CAPD score ≥9. Patients with POD had significantly lower preoperative serum 25(OH)D3 levels, and multivariable analysis showed that vitamin D deficiency (<30 ng/mL) was independently associated with a higher risk of POD (adjusted OR=14.25; 95% CI: 3.33-61.0; P<0.001). The association remained robust after adjusting for postoperative sleep quality (OR=8.15; 95% CI: 1.88-35.3; P=0.005).
Occupational and environmental exposure to inorganic dust during military service is associated with increased risk of sarcoidosis among U.S. Veterans.
In a retrospective nested case-control study of 3,019,636 U.S. Veterans with at least one military occupational code, inorganic dust exposure was associated with a modestly increased risk of sarcoidosis (conditional odds ratio [cOR] 1.08; 95% CI 1.003-1.170). The attributable fraction among the exposed was 7.6%, and the association was stronger when using a modified job exposure matrix (cOR 1.15; 95% CI 1.05-1.27) and when restricted to post-9/11 Veterans (cOR 1.25; 95% CI 1.07-1.47).
Healthy plant-based diets improve sleep quality, while unhealthy plant-based diets worsen it in adults
In a cross-sectional study of 5260 adults, higher adherence to healthy plant-based diets (hPDI) and pro-vegetarian diets (PVDI) was associated with lower PSQI scores and a 12% reduction in odds of poor sleep quality. Conversely, higher overall plant-based diet (oPDI) and unhealthy plant-based diet (uPDI) scores were linked to higher PSQI scores and increased odds of poor sleep. Mediation analyses indicated that the beneficial effects were partly mediated by lower BMI, while the harmful effects were mediated by greater depression and less physical exercise.
Higher body mass index, waist circumference, and body fat percentage are associated with greater somatic symptom severity in perimenopausal women
In a cross-sectional study of 112 Irish perimenopausal women, higher BMI, waist circumference, and body fat percentage were significantly correlated with overall menopausal symptom severity, but after adjusting for confounders, these body composition measures predicted only somatic symptoms (e.g., hot flushes, sleep problems, joint pain). No significant associations were found with psychological or urogenital symptoms. Median BMI was 28.3 kg/m², mean body fat percentage was 34.9%, and median MRS score was 15.0.
Seed cycling capsules with chasteberry reduce PMS symptom severity and frequency over two menstrual cycles
In a single-arm trial, 40 women using Two Moons Seed Cycling Capsules (ZEST and ZEN) showed significant improvements in Menstrual Symptom Questionnaire (MSQ) scores, Numerical Pain Rating Scale (NPRS) scores for cramping, and a 73.86% decrease in sick days due to menstrual issues by the end of Cycle 2. All nine PMS-related symptom parameters improved, including digestive upset, breast tenderness, and productivity interference. Participant satisfaction was high, with 71.79% reporting improved premenstrual/menstrual pain.
Polysomnographic parameters, particularly sleep latency and arousal index, are sensitive early markers of neurocognitive dysfunction following cardiac surgery, and perioperative Citicoline mitigates neurocognitive decline and stabilizes sleep-wake cycles.
In a prospective study of 104 cardiac surgery patients, acute postoperative neurological complications occurred in 35.6% (n=37) on Day 3, and PSG alterations (increased sleep latency, elevated arousal index) on Day 10 correlated with cognitive impairment. In patients with POCD, Citicoline (Group I) showed significant recovery in MoCA scores and faster stabilization of sleep parameters by Day 30 compared to controls (p=0.0016).
Elevated fasting plasma succinate is associated with higher resting heart rate in young sedentary adults
In a cross-sectional analysis of 85 young sedentary adults, higher fasting plasma succinate concentrations were modestly associated with increased resting heart rate (β=0.213, R²=0.074, P=0.046), independent of sex and BMI. Participants with succinate above the cohort median had a resting heart rate about 4 bpm higher than those below the median (95% CI: +0.1 to +8.3, P=0.045). No significant associations were found with heart rate variability parameters.
Physical exercise is associated with better sleep quality among college students, mediated by mobile phone addiction tendency and moderated by psychological resilience.
In a sample of 1,583 college students, physical exercise was significantly negatively associated with sleep quality (β = -0.19, p < 0.001), indicating better sleep quality with more exercise. The relationship was partially mediated by mobile phone addiction tendency (indirect effect = -0.03, 95% CI [-0.04, -0.02]), and psychological resilience moderated the first stage of this mediation, with exercise linked to reduced mobile phone addiction only among students with moderate to high resilience.
An actigraphy-based nap detection algorithm reliably identifies nap-based phenotypes that differentiate individuals with narcolepsy type 1 from healthy controls, and demonstrates that an orexin receptor 2-selective agonist reduces napping to normative levels.
The study developed and validated an actigraphy-based nap detection algorithm with high specificity (93.2%) and accuracy (F1 Area: 83.9%). Applying the algorithm, participants with narcolepsy type 1 had 12.8 fewer nap-free days over 28 days and slept 34 minutes more during the day than controls; treatment with oveporexton (TAK-861) increased nap-free days by 6.1-11.9 and reduced daytime sleep by 12-33 minutes versus baseline.
Physical activity improves executive function in college students through sequential reduction of anxiety and improvement of sleep quality
In a cross-sectional study of 2,033 Chinese college students, physical activity positively predicted executive function, with a direct effect accounting for 49.53% of the total variance. Three mediating pathways were identified: anxiety reduction (31.78%), sleep quality enhancement (14.02%), and a sequential chain of anxiety reduction leading to better sleep quality (4.67%). All mediating effects were statistically significant based on bootstrap confidence intervals.
Newest Studies
All →Cognitive Behavior vs Bright Light Therapy for Insomnia in Women Undergoing Chemotherapy for Breast Cancer: A Randomized Clinical Trial.
JAMA network open, 2026 · observational
Depression prediction and key factors: A comparative analysis of logistic regression and machine learning models.
PloS one, 2026 · observational
Efficacy of benralizumab in reducing cough and/or dyspnea frequency, and improving cough-specific health-related quality of life in patients with severe eosinophilic asthma in Asia.
Therapeutic advances in respiratory disease, 2026 · observational
Home-testing devices for diagnosing obstructive sleep apnoea hypopnoea syndrome - a systematic review and economic evaluation.
Health technology assessment (Winchester, England), 2026 · observational
Recently Updated
All →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.
Valerian, hops, and melatonin may improve sleep quality and reduce insomnia symptoms
This literature review suggests that certain supplements, particularly valerian, hops, and melatonin, could be effective in improving sleep quality and reducing insomnia symptoms. However, the strength of evidence varies, and optimal dosages, formulations, and treatment durations are not established.
Caffeine supplementation may have a detrimental effect on sleep and recovery in athletes
This systematic review of nine randomized controlled trials found that caffeine supplementation can adversely affect sleep parameters in athletes, including sleep quality, quantity, efficiency, number of awakenings, and sleep onset latency. The effects vary based on timing of consumption, habitual caffeine use, and dose.
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).
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