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Cited by 168Coffee research and impactsSleep and Work-Related FatigueNeurotransmitter Receptor Influence on Behavior

Absorption and subjective effects of caffeine from coffee, cola and capsules

Liguori, A·1997·Pharmacology Biochemistry and Behavior
DOI 10.1016/s0091-3057(97)00003-8
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Abstract

Coffee is often perceived as producing greater pharmacological effects than cola. The present study compared the magnitude and rapidity of peak caffeine levels and subjective effects between coffee and cola. Thirteen users of both coffee and cola (mean daily caffeine consumption = 456 mg) ingested 400 mg caffeine via 12 oz unsweetened coffee, 24 oz sugar-free cola or 2 capsules in a random, double-blind, placebo-controlled, within-subjects design. Subjects provided a saliva sample and completed subjective effect scales 15 min before and 30, 60, 90, 120, 180 and 240 min after ingestion. Mean peak saliva caffeine levels did not differ between coffee (9.7 +/- 1.2 micrograms/ml) and cola (9.8 +/- 0.9 micrograms/ml) and appeared to be greater with these beverages than with the capsule (7.8 +/- 0.6 micrograms/ml; p = NS). Saliva caffeine levels peaked at similar times for coffee (42 +/- 5 min) and cola (39 +/- 5 min) but later for capsule (67 +/- 7 min; p = 0.004). There was no main effect of vehicle or interaction of vehicle and drug on magnitude of peak effect or time to peak increase on self-report scales. In summary, peak caffeine absorption, time to peak absorption, and subjective effects do not appear to be influenced by cola vs. coffee vehicle. Perceived differences in the effects of coffee vs. cola may be due to differences in dose, time of day, added sweetener, environmental setting or contingencies.

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Crossref · 10.1016/s0091-3057(97)00003-8

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  • Caffeine concentrations peak in saliva 45 min after ingestion and in serum after about 2 h.

    “Caffeine concentrations peak in saliva 45 min after ingestion (47) and in serum after about 2 h (48).”

    From The Safety of Ingested Caffeine: A Comprehensive Review (2017) · cites this paper as [47]

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Authors
Liguori, A.
Affiliations
University of Vermont (US)
Corresponding author
Liguori, A
Venue
Pharmacology Biochemistry and Behavior
Publisher
Elsevier BV
Published
1997-11
Volume
58
Issue
3
Pages
721-726
ISSN
0091-3057 (ISSN-L)
DOI
10.1016/s0091-3057(97)00003-8
OpenAlex
W2081592829
Semantic Scholar
2b26cf9af50a2fb6efe7371d17e9ce461e3d77d1
Cited by
168
References
29
Citations by year
2026: 2 · 2025: 6 · 2024: 13 · 2023: 8 · 2022: 5 · 2021: 9 · 2020: 13 · 2019: 13 · 2018: 4 · 2017: 13 · 2016: 9 · 2015: 9 · 2014: 9 · 2013: 5 · 2012: 10
FWCI
0.53
Type
journal article
Language
en
Open access
closed
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Pharmacology Biochemistry and Behavior (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health (5r01da004843-06)
  • National Institute on Aging
  • National Institute on Drug Abuse (DA-04843, DA00109)
Topics
  • Health Sciences › Medicine › Pharmacology › Coffee research and impacts
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurotransmitter Receptor Influence on Behavior
Keywords
caffeine, coffee, cola, subjective effects, vehicle effects, caffeine dose
MeSH terms
Adult, Affect, Central Nervous System Stimulants, Behavior, Caffeine, Capsules, Carbonated Beverages, Coffee, Dose-Response Relationship, Drug, Double-Blind Method, Female, Humans, Male, Saliva, Substance Withdrawal Syndrome, Area Under Curve

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