Supplements

Caffeine supplementation in athletes may impair sleep quality and duration, particularly when consumed close to bedtime or in high doses.

This systematic review of nine randomized controlled trials found that caffeine supplementation can have detrimental effects on sleep parameters in athletes, including reduced sleep quality, quantity, and efficiency, as well as increased sleep onset latency and number of awakenings. The effects vary based on timing of consumption, habitual caffeine use, and dose.

1 min readUpdated Jul 7, 20261 RCTsView structured evidence →
Evidence Score42/100
Human RCT★★☆☆☆
Meta-analysis☆☆☆☆☆
Mechanism★★★★★
Safety★★★★
Confidencelow

This article is automatically generated from the structured evidence profile behind the claim above. Scores reflect the quality and quantity of available research, not clinical advice.

Caffeine supplementation in athletes may impair sleep quality and duration, particularly when consumed close to bedtime or in high doses. The current body of evidence comprises 1 study, including 1 randomized controlled trial. EvidenceHub rates the overall confidence at 42/100 (low).

The Claim

Caffeine supplementation in athletes may impair sleep quality and duration, particularly when consumed close to bedtime or in high doses.

This conclusion is most relevant to: Professional athletes (athletic community).

What the Research Shows

The conclusion draws on 1 linked study. Highlights from the cited literature:

  • Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials. (Clinical nutrition ESPEN, 2025) —

How It Works

The proposed biological pathway:

  • Caffeine blocks adenosine receptors in the brain
  • Reduces sleep pressure and delays sleep onset
  • Alters sleep architecture and reduces slow-wave sleep
  • Result: Impaired sleep quality and recovery

Who Might Benefit

Evidence fit by population:

  • Professional athletes (athletic community)

Limitations & Caveats

Important context when interpreting this evidence:

  • Only nine trials were eligible, limiting generalizability
  • Heterogeneity in study designs, caffeine doses, timing, and athlete populations

Frequently Asked Questions

Does caffeine always harm sleep in athletes?

No, the effects vary depending on timing of consumption relative to sleep and exercise, habitual caffeine use, and dose. Some athletes may be less affected.

What sleep parameters are most affected by caffeine?

Sleep onset latency, sleep quality, sleep efficiency, number of awakenings, and overall sleep duration can be negatively impacted.

Why might caffeine affect sleep in athletes specifically?

Athletes often use caffeine for performance enhancement, but its adenosine-blocking effects can interfere with sleep, which is critical for recovery.

How many studies were included in this review?

Nine randomized controlled trials were included from an initial pool of 1469 records.

References

  1. 1.Bodur M, Barkell J, Li X, Sajadi Hezaveh Z. “Does caffeine supplementation affect sleep in athletes? A systematic review of nine randomized controlled trials..” Clinical nutrition ESPEN, 2025. PMID: 39551351 DOI: 10.1016/j.clnesp.2024.11.007
Disclaimer: This article is auto-generated from structured research data for educational purposes only and is not medical advice. Evidence scores reflect the quality and quantity of available research, not clinical recommendations. Always consult a healthcare professional before starting any supplement or intervention.