Evidence map›Paper›PMID 42026645›Full record

ArticleBMC nutrition2026

Caffeine intake from different dietary sources and its association with sleep quality in employed adults.

Kadriye Toprak, Zeyneb Yildirim, Feride Ayyildiz

Abstract read
In one paragraph

Article in BMC nutrition, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from 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.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Kadriye ToprakDepartment of Nutrition and Dietetics, School of Health Sciences, Ankara Medipol University, Ankara, Turkey. kadriye.eken.toprak@gmail.com.ORCID http://orcid.org/0000-0001-8706-8689
Zeyneb YildirimDepartment of Nutrition and Dietetics, Institute of Health Sciences, Ankara Medipol University, Ankara, Turkey.ORCID http://orcid.org/0000-0002-7096-4978
Feride AyyildizDepartment of Nutrition and Dietetics, School of Health Sciences, Gazi University, Ankara, Turkey.ORCID http://orcid.org/0000-0001-7956-5087

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThis study aimed to determine the frequency and amount of consumption of caffeine-containing foods among adults in active employment and to examine the relationship between total daily caffeine intake and sleep quality.

methodsThis cross-sectional study included 428 working adults aged 19–50 years. Caffeine intake was assessed using a quantitative consumption frequency form created by the researchers, while sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Statistical analyses involved appropriate parametric and nonparametric tests, as well as correlation and multiple linear regression models.

resultsThe participants’ average daily caffeine intake was 262.5 [144.0-411.0] mg. The primary sources of caffeine were black coffee (filter/Americano), black tea, and Turkish coffee. Participants with poor sleep quality (71.7%) consumed significantly more caffeine daily than those with good sleep quality. A positive and significant correlation was observed between caffeine intake and PSQI scores. Regression analysis indicated that caffeine consumption, was a significant independent predictor of poor sleep quality (β = 0.147, p = 0.003), particularly affecting sleep duration and disturbances.

conclusionThese results suggest that caffeine intake is a significant lifestyle factor independently associated with sleep quality, and a comprehensive evaluation of consumption sources could benefit public health. Future research should also focus on the timing of caffeine consumption and incorporate objective sleep measures.

Indexed as

CaffeineCaffeine intakePittsburgh Sleep Quality IndexPSQISleep quality

Identifiers

PMID42026645
PMCPMC13245018

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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 OpenQuestion graph.