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Habit

Limit Late-Day Caffeine

Set cutoff for caffeine intake to reduce sleep-latency and fragmentation risk.[1843,1894,1959, etc.]

Superscript reference numbers link to the Sources bibliography.

Moderate Evidence
SleepMoodStress ResilienceEnergy

Composite Rating

3.8/5

Blends evidence depth, community direction, safety friction, and completeness.

Evidence Intensity

100/100

High depth from human/RCT/meta counts

Community Direction

0

Mixed / Neutral • confidence Minimal

Safety Friction

97/100

High signal from adverse/interaction markers

Data Completeness

100%

Studies 24 • mentions 0 • links 35

Not medical advice. This product is for educational and informational purposes only. It does not diagnose, treat, cure, or prevent any disease and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions regarding a medical condition.

FDA disclaimer: These statements have not been evaluated by the Food and Drug Administration. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Results may vary. Not intended for use by pregnant or nursing women, individuals under 18, or those with known medical conditions without physician consultation.

If you are experiencing a medical emergency, call 911 or your local emergency number immediately.

Implementation Blueprint

Classification: add.[1103,1235,1843, etc.]

Best fit: Users with insomnia, anxiety, or fragmented sleep..[1103,1235,1843, etc.]

Goal alignment: Sleep, Mood, Stress Resilience, Energy.[1103,1235,1843, etc.]

Classification

Add

Evidence Tier

MEDIUM

Best Fit

Users with insomnia, anxiety, or fragmented sleep.

Primary Focus

Sleep, Mood

Safety and Pitfalls

  • Taper gradually in high-caffeine users.[1103,1235,1843, etc.]

At-A-Glance Evidence Architecture[1843,1894,1959, etc.]

Clinical Depth

Humans: 309 • RCTs: 22 • Meta: 1

Cohort / Real-World

Cohort signals: 40

Safety Markers

Adverse signals: 16 • Interactions: 0

Evidence Tracking

Freshness, trend, and study timeline for this item

Evidence Tracking

Status

New Evidence

Trend

→ Stable evidence base

Depth

309 total studies · 3 recent

Timeline

19972025

Top Signal Metrics[1843,1894,1959, etc.]

Total indexed

309

Human studies

309

Sleep signals

285

Neuropsych signals

101

Cohort signals

40

Cardiometabolic signals

32

Community Direction Mix[1103,1235,6246]

Weighted direction score: 0 (Mixed / Neutral)

Benefit0
Adverse0
No Effect0
Mixed0

No directional mention volume was resolved; fallback profile metadata is shown in other sections.

Evidence Quality Summary[1843,1894,1959, etc.]

High when replicated human meta-analysis/trial/cohort depth is present for the habit or exposure.

Total indexed

309

Human studies

309

Sleep signals

285

Neuropsych signals

101

Cohort signals

40

Cardiometabolic signals

32

Randomized trials

22

Safety adverse signals

16

Dependency signals

14

In vitro / tissue

4

Meta-analyses

1

Animal-only studies

0

Study Type Breakdown

Distribution of evidence by study design strength

Meta-AnalysesLevel 1a1
Randomized TrialsLevel 1b22
Cohort StudiesLevel 2b40
Human Studies (other)Level 3-4246
All IndexedAll levels309
100

Evidence Strength: High

Composite of study volume, RCTs, and meta-analyses

Top Human Studies[1843,1894,1959, etc.]

PMID 39103929 • 2024 Aug 5

Effects of caffeine intake on pupillary parameters in humans: a systematic review and meta-analysis.

Behavioral and brain functions : BBF

Open PubMed

PMID 39213264 • 2024

Effect of matcha green tea on cognitive functions and sleep quality in older adults with cognitive decline: A randomized controlled study over 12 months.

PloS one

Open PubMed

PMID 26378246 • 2015 Sep 16

Effects of caffeine on the human circadian clock in vivo and in vitro.

Science translational medicine

Open PubMed

PMID 31202686 • 2019 Aug

Resetting the late timing of 'night owls' has a positive impact on mental health and performance.

Sleep medicine

Open PubMed

PMID 40145446 • 2025 Mar-Apr

Caffeine and Beetroot Juice Optimize 1,000-m Performance: Shapley Additive Explanations Analysis.

American journal of men's health

Open PubMed

PMID 31398441 • 2019 Oct 15

Cardiac autonomic activity during sleep deprivation with and without caffeine administration.

Physiology & behavior

Open PubMed

PMID 27044596 • 2016 Apr 4

Does caffeine reduce postoperative bowel paralysis after elective laparoscopic colectomy? (CaCo trial): study protocol for a randomized controlled trial.

Trials

Open PubMed

PMID 33883478 • 2022 Mar-Apr 01

Alcohol and Breast Cancer: Results From the Women's Wellness After Cancer Program Randomized Controlled Trial.

Cancer nursing

Open PubMed

PMID 9042530 • 1997 Jan 30

Caffeine and light effects on nighttime melatonin and temperature levels in sleep-deprived humans.

Brain research

Open PubMed

PMID 18785355 • 2008 Sep

Restoration of risk-propensity during sleep deprivation: caffeine, dextroamphetamine, and modafinil.

Aviation, space, and environmental medicine

Open PubMed

PMID 36653409 • 2023 Jan 18

Brain activity during a working memory task after daily caffeine intake and caffeine withdrawal: a randomized double-blind placebo-controlled trial.

Scientific reports

Open PubMed

PMID 25687152 • 2015 Mar

A school-based sleep education program for adolescents: a cluster randomized trial.

Pediatrics

Open PubMed

PMID 35363563 • 2022 Jun

The Impact of Caffeine Intake on Mental Health Symptoms in Postmenopausal Females with Overactive Bladder Symptoms: A Randomized, Double-Blind, Placebo-Controlled Trial.

Journal of women's health (2002)

Open PubMed

PMID 12424548 • 2002 Nov

Effects of caffeine, sleep loss, and stress on cognitive performance and mood during U.S. Navy SEAL training. Sea-Air-Land.

Psychopharmacology

Open PubMed

PMID 34775507 • 2022 Feb 1

Individualized Studies of Triggers of Paroxysmal Atrial Fibrillation: The I-STOP-AFib Randomized Clinical Trial.

JAMA cardiology

Open PubMed

PMID 23094031 • 2012

In-car nocturnal blue light exposure improves motorway driving: a randomized controlled trial.

PloS one

Open PubMed

PMID 28885372 • 2017 Sep

Light therapy for multiple sclerosis-associated fatigue: Study protocol for a randomized controlled trial.

Medicine

Open PubMed

PMID 20946437 • 2011 Sep

Caffeine protects against increased risk-taking propensity during severe sleep deprivation.

Journal of sleep research

Open PubMed

PMID 24611526 • 2014 Nov

Building a self-regulatory model of sleep deprivation and deception: the role of caffeine and social influence.

The Journal of applied psychology

Open PubMed

PMID 17765011 • 2008 Jul

Sleep deprivation reduces perceived emotional intelligence and constructive thinking skills.

Sleep medicine

Open PubMed

PMID 32933332 • 2020 Sep-Oct

TNFα G308A genotype, resilience to sleep deprivation, and the effect of caffeine on psychomotor vigilance performance in a randomized, double-blind, placebo-controlled, crossover study.

Chronobiology international

Open PubMed

PMID 35504555 • 2022 Jul

Modafinil ameliorates the decline in pronunciation-related working memory caused by 36-h acute total sleep deprivation: An ERP study.

Neurobiology of learning and memory

Open PubMed

PMID 10088991 • 1999 Jan

Effects of discontinuing coffee intake on iron deficient Guatemalan toddlers' cognitive development and sleep.

Early human development

Open PubMed

PMID 36841492 • 2023 Mar-Apr

Sleep physiology, pathophysiology, and sleep hygiene.

Progress in cardiovascular diseases

Open PubMed

Community Report Frequency[1103,1235,6246]

Benefit reports: 0

Adverse reports: 0

No-effect reports: 0

Mixed reports: 0

Unclear reports: 0

Signal confidence: 0.00

Top Reported Effects[1103,1235,6246]

Benefits

  • Sleep: 1
  • Mood: 1
  • Stress Resilience: 1
  • Energy: 1

Adverse

  • Taper gradually in high-caffeine users: 1

No Effect

  • insufficient no-effect reports captured: 0

Community confidence 0.00 with mentions: benefit 0, adverse 0, no-effect 0.

Community Evidence Examples[1103,1235,6246]

aggregate • unclear

No directional first-hand mentions captured in the current community corpus; source links are retained for traceability.

Open mention

Primary Source Links

Evidence Sources

  • https://pubmed.ncbi.nlm.nih.gov/?term=(%22caffeine%22%20AND%20sleep%20AND%20humans%5BMeSH%20Terms%5D)%20AND%20(habit%5BTitle%2FAbstract%5D%20OR%20behavior%5BTitle%2FAbstract%5D%20OR%20exposure%5BTitle%2FAbstract%5D%20OR%20lifestyle%5BTitle%2FAbstract%5D)
  • https://pubmed.ncbi.nlm.nih.gov/?term=(%22caffeine%22%20AND%20sleep%20AND%20humans%5BMeSH%20Terms%5D)%20AND%20humans%5BMeSH%20Terms%5D%20AND%20(habit%5BTitle%2FAbstract%5D%20OR%20behavior%5BTitle%2FAbstract%5D%20OR%20exposure%5BTitle%2FAbstract%5D%20OR%20lifestyle%5BTitle%2FAbstract%5D)
  • https://pubmed.ncbi.nlm.nih.gov/?term=(%22caffeine%22%20AND%20sleep%20AND%20humans%5BMeSH%20Terms%5D)%20AND%20humans%5BMeSH%20Terms%5D%20AND%20(habit%5BTitle%2FAbstract%5D%20OR%20behavior%5BTitle%2FAbstract%5D%20OR%20exposure%5BTitle%2FAbstract%5D%20OR%20lifestyle%5BTitle%2FAbstract%5D)%20AND%20randomized%20controlled%20trial%5BPublication%20Type%5D
  • https://pubmed.ncbi.nlm.nih.gov/?term=(%22caffeine%22%20AND%20sleep%20AND%20humans%5BMeSH%20Terms%5D)%20AND%20humans%5BMeSH%20Terms%5D%20AND%20(habit%5BTitle%2FAbstract%5D%20OR%20behavior%5BTitle%2FAbstract%5D%20OR%20exposure%5BTitle%2FAbstract%5D%20OR%20lifestyle%5BTitle%2FAbstract%5D)%20AND%20meta-analysis%5BPublication%20Type%5D
  • https://pubmed.ncbi.nlm.nih.gov/?term=(%22caffeine%22%20AND%20sleep%20AND%20humans%5BMeSH%20Terms%5D)%20AND%20humans%5BMeSH%20Terms%5D%20AND%20(habit%5BTitle%2FAbstract%5D%20OR%20behavior%5BTitle%2FAbstract%5D%20OR%20exposure%5BTitle%2FAbstract%5D%20OR%20lifestyle%5BTitle%2FAbstract%5D)%20AND%20(sleep%5BTitle%2FAbstract%5D%20OR%20insomnia%5BTitle%2FAbstract%5D%20OR%20circadian%5BTitle%2FAbstract%5D)
  • https://pubmed.ncbi.nlm.nih.gov/?term=(%22caffeine%22%20AND%20sleep%20AND%20humans%5BMeSH%20Terms%5D)%20AND%20humans%5BMeSH%20Terms%5D%20AND%20(habit%5BTitle%2FAbstract%5D%20OR%20behavior%5BTitle%2FAbstract%5D%20OR%20exposure%5BTitle%2FAbstract%5D%20OR%20lifestyle%5BTitle%2FAbstract%5D)%20AND%202018%3A3000%5Bpdat%5D
  • https://pubmed.ncbi.nlm.nih.gov/39103929/
  • https://pubmed.ncbi.nlm.nih.gov/39213264/
  • https://pubmed.ncbi.nlm.nih.gov/26378246/
  • https://pubmed.ncbi.nlm.nih.gov/31202686/
  • https://pubmed.ncbi.nlm.nih.gov/40145446/
  • https://pubmed.ncbi.nlm.nih.gov/31398441/
  • https://pubmed.ncbi.nlm.nih.gov/27044596/
  • https://pubmed.ncbi.nlm.nih.gov/33883478/
  • https://pubmed.ncbi.nlm.nih.gov/9042530/
  • https://pubmed.ncbi.nlm.nih.gov/18785355/
  • https://pubmed.ncbi.nlm.nih.gov/36653409/
  • https://pubmed.ncbi.nlm.nih.gov/25687152/
  • https://pubmed.ncbi.nlm.nih.gov/35363563/
  • https://pubmed.ncbi.nlm.nih.gov/12424548/

Community Sources

  • https://old.reddit.com/search.json?raw_json=1&sort=relevance&t=year&limit=8&q=%22limit%20late-day%20caffeine%22%20(exercise%20OR%20training%20OR%20sleep%20OR%20habit%20OR%20side%20effects%20OR%20experience%20OR%20results)%20(subreddit%3AFitness%20OR%20subreddit%3Abodyweightfitness%20OR%20subreddit%3Aweightroom%20OR%20subreddit%3Arunning%20OR%20subreddit%3ACycling%20OR%20subreddit%3Aswimming%20OR%20subreddit%3AHIIT%20OR%20subreddit%3Ayoga%20OR%20subreddit%3Abiohackers%20OR%20subreddit%3Alongevity%20OR%20subreddit%3Ameditation%20OR%20subreddit%3Asleep%20OR%20subreddit%3Astopsmoking%20OR%20subreddit%3Astopdrinking%20OR%20subreddit%3Aleaves%20OR%20subreddit%3Adecaf%20OR%20subreddit%3Adecidingtobebetter)
  • https://old.reddit.com/search.json?raw_json=1&sort=relevance&t=year&limit=12&q=limit%20late-day%20caffeine
  • https://www.reddit.com/search/?q=Limit%20Late-Day%20Caffeine

Scientific Evidence Notes[1843,1894,1959, etc.]

1. PubMed triage evidence summary: Limit Late-Day Caffeine

PUBMED • Human lifestyle/habit literature

Counts from structured habit/exposure PubMed query set.

Outcome: Humans 25, RCT 3, meta 1, cohort 3, sleep signals 23, cardiometabolic signals 1.[1843,1894,1959, etc.]

Open source
2. Effects of caffeine intake on pupillary parameters in humans: a systematic review and meta-analysis.

PUBMED • 2024 • Human evidence curation set

PMID 39103929 from Behavioral and brain functions : BBF.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
3. Effects of caffeine on the human circadian clock in vivo and in vitro.

PUBMED • 2015 • Human evidence curation set

PMID 26378246 from Science translational medicine.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
4. Resetting the late timing of 'night owls' has a positive impact on mental health and performance.

PUBMED • 2019 • Human evidence curation set

PMID 31202686 from Sleep medicine.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
5. Effect of matcha green tea on cognitive functions and sleep quality in older adults with cognitive decline: A randomized controlled study over 12 months.

PUBMED • 2024 • Human evidence curation set

PMID 39213264 from PloS one.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
6. Caffeine and Beetroot Juice Optimize 1,000-m Performance: Shapley Additive Explanations Analysis.

PUBMED • 2025 • Human evidence curation set

PMID 40145446 from American journal of men's health.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
7. Cardiac autonomic activity during sleep deprivation with and without caffeine administration.

PUBMED • 2019 • Human evidence curation set

PMID 31398441 from Physiology & behavior.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
8. Does caffeine reduce postoperative bowel paralysis after elective laparoscopic colectomy? (CaCo trial): study protocol for a randomized controlled trial.

PUBMED • 2016 • Human evidence curation set

PMID 27044596 from Trials.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
9. Alcohol and Breast Cancer: Results From the Women's Wellness After Cancer Program Randomized Controlled Trial.

PUBMED • 2022 • Human evidence curation set

PMID 33883478 from Cancer nursing.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
10. Caffeine and light effects on nighttime melatonin and temperature levels in sleep-deprived humans.

PUBMED • 1997 • Human evidence curation set

PMID 9042530 from Brain research.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
11. Restoration of risk-propensity during sleep deprivation: caffeine, dextroamphetamine, and modafinil.

PUBMED • 2008 • Human evidence curation set

PMID 18785355 from Aviation, space, and environmental medicine.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
12. Brain activity during a working memory task after daily caffeine intake and caffeine withdrawal: a randomized double-blind placebo-controlled trial.

PUBMED • 2023 • Human evidence curation set

PMID 36653409 from Scientific reports.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
13. A school-based sleep education program for adolescents: a cluster randomized trial.

PUBMED • 2015 • Human evidence curation set

PMID 25687152 from Pediatrics.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
14. The Impact of Caffeine Intake on Mental Health Symptoms in Postmenopausal Females with Overactive Bladder Symptoms: A Randomized, Double-Blind, Placebo-Controlled Trial.

PUBMED • 2022 • Human evidence curation set

PMID 35363563 from Journal of women's health (2002).

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
15. Effects of caffeine, sleep loss, and stress on cognitive performance and mood during U.S. Navy SEAL training. Sea-Air-Land.

PUBMED • 2002 • Human evidence curation set

PMID 12424548 from Psychopharmacology.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
16. Individualized Studies of Triggers of Paroxysmal Atrial Fibrillation: The I-STOP-AFib Randomized Clinical Trial.

PUBMED • 2022 • Human evidence curation set

PMID 34775507 from JAMA cardiology.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
17. In-car nocturnal blue light exposure improves motorway driving: a randomized controlled trial.

PUBMED • 2012 • Human evidence curation set

PMID 23094031 from PloS one.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
18. Light therapy for multiple sclerosis-associated fatigue: Study protocol for a randomized controlled trial.

PUBMED • 2017 • Human evidence curation set

PMID 28885372 from Medicine.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
19. Caffeine protects against increased risk-taking propensity during severe sleep deprivation.

PUBMED • 2011 • Human evidence curation set

PMID 20946437 from Journal of sleep research.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
20. Building a self-regulatory model of sleep deprivation and deception: the role of caffeine and social influence.

PUBMED • 2014 • Human evidence curation set

PMID 24611526 from The Journal of applied psychology.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
21. Sleep deprivation reduces perceived emotional intelligence and constructive thinking skills.

PUBMED • 2008 • Human evidence curation set

PMID 17765011 from Sleep medicine.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
22. TNFα G308A genotype, resilience to sleep deprivation, and the effect of caffeine on psychomotor vigilance performance in a randomized, double-blind, placebo-controlled, crossover study.

PUBMED • 2020 • Human evidence curation set

PMID 32933332 from Chronobiology international.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
23. Modafinil ameliorates the decline in pronunciation-related working memory caused by 36-h acute total sleep deprivation: An ERP study.

PUBMED • 2022 • Human evidence curation set

PMID 35504555 from Neurobiology of learning and memory.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
24. Effects of discontinuing coffee intake on iron deficient Guatemalan toddlers' cognitive development and sleep.

PUBMED • 1999 • Human evidence curation set

PMID 10088991 from Early human development.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source
25. Sleep physiology, pathophysiology, and sleep hygiene.

PUBMED • 2023 • Human evidence curation set

PMID 36841492 from Progress in cardiovascular diseases.

Outcome: See linked PubMed abstract for methods and outcomes.[1843,1894,1959, etc.]

Open source