Evidence map›Paper›PMID 27538675›Full record

ArticlePsychopharmacology2016

Sweet taste pleasantness is modulated by morphine and naltrexone.

Marie Eikemo, Guro E Løseth, Tom Johnstone, Johannes Gjerstad, Frode Willoch, Siri Leknes

Open access · greenAbstract read
PubMed Publisher
In one paragraph

Article in Psychopharmacology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 37 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
37citing papers in PubMed, 3 pooled it
5.5field-weighted citation impact, top 4% of its field
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

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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

37 citing papers in PubMed, 3 syntheses or guidelines pooled it, 99 citations in OpenAlex.

  1. Pooled it
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  3. Intact responses to non-drug rewards in long-term opioid maintenance treatment.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2019
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  12. Pleasurable music activates cerebral µ-opioid receptors: a combined PET-fMRI study.European journal of nuclear medicine and molecular imaging · 2025
    Article
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  20. Opioid antagonism in humans: a primer on optimal dose and timing for central mu-opioid receptor blockade.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2023
    Article
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

6 authors at 2 institutions in 2 countries.

Marie EikemoNorwegian Center for Addiction Research (SERAF), University of Oslo, PO BOX 1039 Blindern, 0315, Oslo, Norway. m.h.eikemo@medisin.uio.no.
Guro E LøsethDepartment of Psychology, University of Oslo, Oslo, Norway.
Tom JohnstoneSchool of Psychology and CLS, University of Reading, Reading, UK.
Johannes GjerstadNorwegian Institute of Occupational Health (STAMI), Oslo, Norway.
Frode WillochDepartment of Basic Medical Sciences, University of Oslo, Oslo, Norway.
Siri LeknesDepartment of Psychology, University of Oslo, Oslo, Norway.
University of Oslo · NOUniversity of Reading · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundRodent models highlight the key role of μ-opioid receptor (MOR) signaling in palatable food consumption. In humans, however, the effects of MOR stimulation on eating and food liking remain unclear.

objectivesHere, we tested sweet pleasantness experience in humans following MOR drug manipulations. We hypothesized that behaviors regulated by the endogenous MOR system would be enhanced by MOR agonism and decreased by antagonism. In line with rodent findings, we expected the strongest drug effects for the sweetest (high-calorie) sucrose stimuli. As very sweet stimuli are considered aversive by many people (called sweet dislikers), we also assessed whether MOR manipulations affect pleasantness ratings of sucrose-water stimuli differently depending on subjective and objective value.

methodsIn a bidirectional psychopharmacological cross-over study, 49 healthy men underwent a sweet taste paradigm following double-blind administration of the MOR agonist morphine, placebo, and the opioid antagonist naltrexone.

resultsAs hypothesized, MOR stimulation with morphine increased pleasantness of the sweetest of five sucrose solutions, without enhancing pleasantness of the lower-sucrose solutions. For opioid antagonism, an opposite pattern was observed for the sweetest drink only. The observed drug effects on pleasantness of the sweetest drink did not differ between sweet likers and dislikers.

conclusionsThe bidirectional effect of agonist and antagonist treatment aligns with rodent findings showing that MOR manipulations most strongly affect the highest-calorie foods. We speculate that the MOR system promotes survival in part by increasing concordance between the objective (caloric) and subjective (hedonic) value of food stimuli, so that feeding behavior becomes more focused on the richest food available.

Indexed as

SucroseSweetening AgentsAdultAnalgesics, OpioidCross-Over StudiesDouble-Blind MethodEatingEmotionsFood PreferencesHumansMaleMorphineNaltrexoneNarcotic AntagonistsReceptors, Opioid, muTasteAnalgesics, OpioidMorphineNaltrexoneNarcotic AntagonistsOPRM1 protein, humanReceptors, Opioid, muSucroseSweetening AgentsFoodHumanMorphineNaltrexoneOpioid system

Identifiers

PMID27538675
OpenAlexW2514917568

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

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.