Trial reportSleep2025
Dose and timing effects of caffeine on subsequent sleep: a randomized clinical crossover trial.
Trial report in Sleep, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
24 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- The Caffeinated Brain Part 1: The Effects of Caffeine on Event-Related Potentials (ERPs)-A Systematic and Mechanistic Review.Nutrients · 2026Pooled it
- The Caffeinated Brain Part 2: The Effect of Caffeine on Sleep-Related Electroencephalography (EEG)-A Systematic and Mechanistic Review.Nutrients · 2026Pooled it
- Differential effects of caffeine, acute aerobic exercise, and placebo on mental fatigue.PloS one · 2026Trial
- Coffee consumption patterns and sleep quality among Saudi Youth: A cross-sectional study.Sleep medicine: X · 2026Article
- Beverage Co-Consumption Profiles, Sleep, and Fatigue in Professional Army Personnel.Nutrients · 2026Article
- Article
- PSQI-based severity-ordered sleep-quality strata and associated clinical and psychosocial factors among adults with untreated obstructive sleep apnea: a multicenter cross-sectional study.BMC public health · 2026Article
- One Step Further: Integrating Evidence-Based Guidelines into Practice to Address Environmental Challenges at the Men's 2026 FIFA World Cup.Sports medicine (Auckland, N.Z.) · 2026Review
- Optimizing Athlete Travel for Performance: A Scientific Blueprint for Athletes, Coaches, and Sports Medicine Staff.Sports medicine (Auckland, N.Z.) · 2026Review
- Caffeine intake from different dietary sources and its association with sleep quality in employed adults.BMC nutrition · 2026Article
- Chrysanthemum morifolium extract protects HT22 cells from oxidative stress and enhances sleep via GABAergic modulation: contribution of luteolin-7-glucoside.Journal of the science of food and agriculture · 2026Article
- The multidimensional effects of sleep quality in young adults: the relationship between auditory performance, sound tolerance, and anxiety.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2026Article
- The effect of caffeinated beverage consumption on the relationship between sleep quality and major adverse cardiovascular events: Sleep Heart Health Study.Sleep advances : a journal of the Sleep Research Society · 2026Article
- Evaluating the association between caffeine exposure and sleep duration and trouble sleeping in adults.Sleep advances : a journal of the Sleep Research Society · 2026Article
- Caffeine and human performance: from molecular mechanisms to exercise and recovery.Frontiers in physiology · 2026Review
- Sleep and Substance Use Among Firefighters: Associations with Alcohol, Caffeine, and Nicotine Use.Nature and science of sleep · 2026Article
- Caffeine consumption patterns, motivations, and adverse effects among Brazilian esports players: a cross-sectional study.Journal of the International Society of Sports Nutrition · 2025Article
- Device for Electrochemical Caffeine Analysis in Fluids (DECAF): A Stir-Bar-Embedded Sensor for Real-Time Caffeine Analysis in Commercial and Homemade Beverages.Small (Weinheim an der Bergstrasse, Germany) · 2025Article
- A Mixed Method Study Exploring Children and Young People's Perception of Energy Drinks and Analysing Consumption Patterns.Journal of human nutrition and dietetics : the official journal of the British Dietetic Association · 2025Article
- Eat Well, Sleep Well: Exploring the Association Between Eating Behavior and Sleep Quality.Nutrients · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
STUDY
objectivesTo investigate the effect of a typical dose of caffeine and a high dose of caffeine consumed in the morning, afternoon, and evening on subsequent sleep.
methodsUsing a placebo-controlled, double-blind, randomized crossover design, 23 males (25.3 ± 5.0 years) with a moderate habitual caffeine intake (<300 mg∙day-1) completed seven conditions: placebo, and 100 and 400 mg of caffeine consumed 12, 8, and 4 hours prior to bedtime, with a 48-hour washout. In-home partial polysomnography and sleep diaries were used to assess sleep. Linear mixed models estimated the effect of each condition.
resultsNo significant effect on objective or subjective sleep occurred with the 100 mg dose of caffeine compared with the placebo (p > .05), but significant effects occurred with the 400 mg dose (p < .05). Significant delays in sleep initiation and alterations to sleep architecture were observed when 400 mg was consumed within 12 hours of bedtime (p < .05), and significantly greater sleep fragmentation occurred when 400 mg was consumed within 8 hours of bedtime (p < .05). Additionally, perceived sleep quality was significantly reduced when 400 mg was consumed 4 hours prior to bedtime (-34.02%, p = .006) but not at 8 or 12 hours.
conclusionsA 100 mg dose of caffeine can be consumed up to 4 hours prior to bedtime, but 400 mg may negatively impact sleep when consumed as one dose within 12 hours of bedtime, with the adverse influence on sleep increasing the closer consumption occurs to bedtime. The discrepancy between objective and subjective sleep quality suggests that individuals may have difficulty accurately perceiving the influence of caffeine on sleep quality. CLINICAL
trial registrationAustralian and New Zealand Clinical Trials Registry, registration number: ACTRN12621001625864, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12621001625864.
Indexed as
Identifiers
What Socratic holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.