14
17
9
↑14
↓17
—9
Evidence suggests Caffeine maydecreaseSleep duration.
18 studies (40 claims)
Conflicting evidence
Typical effective dose 32.45 (5.13–74.17) mgacross 4 dosed studies
Study Claims
| Intervention | Direction | Endpoint | Type | Population | Dosage | Title |
|---|---|---|---|---|---|---|
| caffeine supplements | No effect - showed varying results concerning | other sleep-related variables | Human | professional athletes | Not specified | Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. |
| caffeine supplements | No effect - showed varying results concerning | sleep efficiency | Human | professional athletes | Not specified | Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. |
| caffeine supplements | No effect - showed varying results concerning | sleep onset latency | Human | professional athletes | Not specified | Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. |
| caffeine supplements | No effect - showed varying results concerning | sleep quality | Human | professional athletes | Not specified | Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. |
| caffeine supplements | No effect - showed varying results concerning | sleep quantity | Human | professional athletes | Not specified | Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. |
| caffeine supplementation | Decreases - could have a detrimental effect on | sleep | Human | professional athletes | Not specified | Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. |
| caffeine use in increasing amounts | Decreases - associated with decreased | sleep duration | Human | — | Mean caffeine consumption varied from 212 to 285 mg/day. | The effects of caffeinated products on sleep and functioning in the military population: A focused review.cited 13× |
| chronic caffeine intake | No effect - associated with | non-restful sleep | Human | the general population | Mean caffeine consumption varied from 212 to 285 mg/day. | The effects of caffeinated products on sleep and functioning in the military population: A focused review.cited 13× |
| chronic caffeine intake | Decreases - associated with decreased | sleep duration | Human | the general population | Mean caffeine consumption varied from 212 to 285 mg/day. | The effects of caffeinated products on sleep and functioning in the military population: A focused review.cited 13× |
| Caffeine and energy drink consumption | No effect - may maintain | some aspects of performance stemming from insufficient sleep | Human | deployed personnel | Mean caffeine consumption varied from 212 to 285 mg/day. | The effects of caffeinated products on sleep and functioning in the military population: A focused review.cited 13× |
| caffeine supplementation | Increases - had the highest prevalence and magnitude | negative effects on sleep onset | Human | athletes | — | Risk or benefit? Side effects of caffeine supplementation in sport: a systematic review.cited 48× |
| caffeine supplementation | Increases - impaired | sleep latency | Human | female athletes taking a low-dose monophasic oral contraceptive steroid | 6 mg/kg body mass anhydrous caffeine. | The Effect of Caffeine Ingestion during Evening Exercise on Subsequent Sleep Quality in Females.cited 24× |
| caffeine supplementation | Decreases - impaired | subsequent quality of sleep | Human | female athletes taking a low-dose monophasic oral contraceptive steroid | 6 mg/kg body mass anhydrous caffeine. | The Effect of Caffeine Ingestion during Evening Exercise on Subsequent Sleep Quality in Females.cited 24× |
| Habitual daily caffeine consumption | Increases - was positively correlated with | wake after sleep onset (WASO) duration on the recovery night | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| Acute caffeine intake | Decreases - decreased | delta power spectral density during NREM sleep | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| Acute caffeine intake | Decreases - decreased | N3 sleep stage duration | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| Acute caffeine intake | No effect - altered | recovery sleep continuity | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| Acute caffeine intake | No effect - altered | recovery sleep organization | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| Acute caffeine intake | No effect - altered | recovery sleep stability | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| Acute caffeine intake | Decreases - decreased | recovery total sleep time (TST) | Human | participants | 2.5 mg/kg administered twice during continuous wakefulness. | Caffeine Intake Alters Recovery Sleep after Sleep Deprivation. |
| avoidance of caffeine | Increases - promising indications | sleep | Human | children and young people (0-18 y) | Not specified | Empirical research evaluating the effects of non-traditional approaches to enhancing sleep in typical and clinical children and young people.cited 15× |
| combined theanine and caffeine (TC) | No effect - no differences | sleep-onset latency | Human | healthy young women | 50 mg theanine, 30 mg caffeine | Theanine maintains sleep quality in healthy young women by suppressing the increase in caffeine-induced wakefulness after sleep onset.cited 5× |
| caffeine | No effect - no differences | sleep-onset latency | Human | healthy young women | 50 mg theanine, 30 mg caffeine | Theanine maintains sleep quality in healthy young women by suppressing the increase in caffeine-induced wakefulness after sleep onset.cited 5× |
| caffeine intake | Decreases - decreased | duration of deep sleep (N3 and N4) | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine intake | Increases - increased | duration of light sleep (N1) | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine intake | Decreases - decreased | proportion of deep sleep (N3 and N4) | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine intake | Increases - increased | proportion of light sleep (N1) | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine consumption | Decreases - reduced | sleep efficiency | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine consumption | Increases - increase | sleep onset latency | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine consumption | Decreases - reduced | total sleep time | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| caffeine consumption | Increases - increase | wake after sleep onset | Human | — | — | The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.cited 57× |
| combined EGCG and L-Theanine total content in relation to caffeine ratio | No effect - showed a slightly stronger correlation with | sleep duration | Animal | — | 58.9 mg g-1 caffeine in GE, comparable to 25 mg kg-1 pure caffeine. | The polyphenol/caffeine ratio determines the arousal-inducing properties of the green tea ethanol extract. |
| ratio of EGCG to caffeine in GE | No effect - was more closely associated with | sleep duration | Animal | — | 58.9 mg g-1 caffeine in GE, comparable to 25 mg kg-1 pure caffeine. | The polyphenol/caffeine ratio determines the arousal-inducing properties of the green tea ethanol extract. |
| caffeine supplement (CAF; 6 mg∙kg⁻¹) | Decreases - impaired | sleep efficiency | Human | trained runners | — | Impact of Caffeine Intake on 800-m Running Performance and Sleep Quality in Trained Runners.cited 18× |
| caffeine supplement (CAF; 6 mg∙kg⁻¹) | Increases - increased | sleep latency | Human | trained runners | — | Impact of Caffeine Intake on 800-m Running Performance and Sleep Quality in Trained Runners.cited 18× |
| caffeine supplement (CAF; 6 mg∙kg⁻¹) | Decreases - decreased | total sleep time | Human | trained runners | — | Impact of Caffeine Intake on 800-m Running Performance and Sleep Quality in Trained Runners.cited 18× |
| caffeine supplement (CAF; 6 mg∙kg⁻¹) | Increases - increased | wake after sleep onset | Human | trained runners | — | Impact of Caffeine Intake on 800-m Running Performance and Sleep Quality in Trained Runners.cited 18× |
| caffeine ingestion | Decreases - impairs | sleep quality | Human | — | — | Impact of Caffeine Intake on 800-m Running Performance and Sleep Quality in Trained Runners.cited 18× |
| caffeine consumption | Increases - contributing to | chronic sleep loss | Human | adolescents | Not available | Insufficient sleep in adolescents and young adults: an update on causes and consequences.cited 877× |
| caffeine | No effect - modifies | sleep | Human | athletes | — | Caffeine and Exercise: What Next?cited 92× |
| caffeine | No effect - did not affect | sleep | Human | depressed patients | 60 mg or 120 mg daily. | Low dose of caffeine enhances the efficacy of antidepressants in major depressive disorder and the underlying neural substrates.cited 29× |
| caffeine | Increases - may help improve | sleep disorders | Human | — | Not specified | Uncovering the effects and mechanisms of tea and its components on depression, anxiety, and sleep disorders: A comprehensive review.cited 3× |
| caffeine | No effect - hypothesized impact on | sleep disorders | Human | — | Not specified | Alzheimer's disease and sleep disorders: Insights into the possible disease connections and the potential therapeutic targets.cited 20× |
| caffeine | Decreases - markedly decrease | sleep efficiency | Animal | zebrafish larvae | 31.25 μM, 62.5 μM, and 120 μM | The Effect of Caffeine Exposure on Sleep Patterns in Zebrafish Larvae and Its Underlying Mechanism. |
| caffeine | Increases - could induce | sleep pattern disorders | Animal | zebrafish larvae | 31.25 μM, 62.5 μM, and 120 μM | The Effect of Caffeine Exposure on Sleep Patterns in Zebrafish Larvae and Its Underlying Mechanism. |
| caffeine | Decreases - markedly decrease | total sleep time | Animal | zebrafish larvae | 31.25 μM, 62.5 μM, and 120 μM | The Effect of Caffeine Exposure on Sleep Patterns in Zebrafish Larvae and Its Underlying Mechanism. |
| Caffeine | Increases - have a role in facilitating sleep schedule changes | sleep schedule changes | Human | athletes | Not specified | Medications for Sleep Schedule Adjustments in Athletes.cited 7× |