ReviewPhilosophical transactions of the Royal Society of London. Series B, Biological sciences2013
The effect of raising and lowering tryptophan levels on human mood and social behaviour.
Review in Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 46 papers, 2 of them syntheses that pooled 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.
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.
Who cites it
46 citing papers in PubMed, 2 syntheses or guidelines pooled it, 97 citations in OpenAlex.
- The habenula in mood disorders: A systematic review of human studies.Molecular psychiatry · 2025Pooled it
- Effects of physical exercise interventions on multidimensional health outcomes in patients with substance use disorders: a network meta-analysis.Frontiers in psychiatry · 2025Pooled it
- No effects of acute tryptophan depletion on anxiety or mood in weight-recovered female patients with anorexia nervosa.European archives of psychiatry and clinical neuroscience · 2023Trial
- Tryptophan-enriched diet or 5-hydroxytryptophan supplementation given in a randomized controlled trial impacts social cognition on a neural and behavioral level.Scientific reports · 2021Trial
- Influences of glutamine administration on response selection and sequence learning: a randomized-controlled trial.Scientific reports · 2017Trial
- Cortico-limbic connectivity in MAOA-L carriers is vulnerable to acute tryptophan depletion.Human brain mapping · 2017Trial
- Empathic accuracy and oxytocin after tryptophan depletion in adults at risk for depression.Psychopharmacology · 2016Trial
- Reduction in behavior problems with omega-3 supplementation in children aged 8-16 years: a randomized, double-blind, placebo-controlled, stratified, parallel-group trial.Journal of child psychology and psychiatry, and allied disciplines · 2015Trial
- Effects of a caloric restriction weight loss diet on tryptophan metabolism and inflammatory biomarkers in overweight adults.European journal of nutrition · 2015Trial
- Effects of acute treatment with a tryptophan-rich protein hydrolysate on plasma amino acids, mood and emotional functioning in older women.Psychopharmacology · 2014Trial
- Pet Nutrition and the Unmeasured Owner Outcome: A Bidirectional Framework for Relational Value in Human-Animal Relationships.Animals : an open access journal from MDPI · 2026Review
- Physiological and Behavioral Evaluation of Shelter Dogs During Veterinary Routine Health Checks.Veterinary sciences · 2025Article
- Can social isolation alleviate symptoms of anxiety and depression disorders?Frontiers in psychiatry · 2025Review
- The Intersection of Ultra-Processed Foods, Neuropsychiatric Disorders, and Neurolaw: Implications for Criminal Justice.NeuroSci · 2024Article
- A Low FODMAP Diet Supplemented with L-Tryptophan Reduces the Symptoms of Functional Constipation in Elderly Patients.Nutrients · 2024Article
- Inflammation, stress and depression: An exploration of ketamine's therapeutic profile.Drug discovery today · 2023Review
- Beneficial Effect of Increased Tryptophan Intake on Its Metabolism and Mental State of the Elderly.Nutrients · 2023Article
- Demonstrating a link between diet, gut microbiota and brain:Frontiers in nutrition · 2023Article
- Antimicrobial treatment improves tryptophan metabolism and mood of patients with small intestinal bacterial overgrowth.Nutrition & metabolism · 2022Article
- Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
1 author at 1 institution in 1 country.
Funding
Abstract
Acute tryptophan depletion (ATD) studies indicate that low serotonin can lower mood and also increase aggression, although results vary somewhat between studies with similar participants. Lowering of mood after ATD is related to the susceptibility of the study participants to clinical depression, and some participants show no effect on mood. This indicates that low serotonin can contribute to lowered mood, but cannot-by itself-cause lowered mood, unless other unknown systems interact with serotonin to lower mood. Studies using tryptophan supplementation demonstrate that increased serotonin can decrease quarrelsomeness and increase agreeableness in everyday life. Social interactions that are more agreeable and less quarrelsome are associated with better mood. Thus, serotonin may have direct effects on mood, but may also be able to influence mood through changes in social behaviour. The increased agreeableness and decreased quarrelsomeness resulting from increases in serotonin will help foster congenial relations with others and should help to increase social support. As social support and social isolation have an important relationship with both physical and mental health, more research is needed on the implications of the ability of serotonin to modulate social behaviour for the regulation of mood, and for future physical and mental health.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
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.