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Metabolic & Cardiometabolic

anabolic-androgenic steroids worsens cognitive function

In plain terms: Do anabolic steroids impair cognitive function?

Leans support Metabolic & Cardiometabolic 🔬 Includes disconfirming

Part of: 💊 anabolic-androgenic steroids

RefutedContestedStrong support
consensus score 0.58

Leans yes — long-term high-dose users show poorer cognition and brain changes on imaging, so the evidence points to real cognitive harm, with the caveat that much of it comes from a single research group.

📅 Last reviewed: 2026-07-14

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: Population patterns (Observational)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

9 support 0 contradict 1 tested null 4 mixed · 14 sources, 6 independent groups

What the evidence shows

Causal-review pass (2026-08-14) — `causal_basis: association-only`. Cannot be randomised (dosing healthy people with supraphysiological androgens for a cognitive endpoint is not an ethical trial), so every human appraisal is observational and self-selected.

The evidence (14)

SourceGradeStanceQualityFinding
Buhl LF et al
2024 · study_type: observational
observational tested-null low Human protocol paper (FIDO-DK, Denmark) for a cross-sectional cohort study of illicit AAS users vs matched controls; cognitive function is listed among planned mental-health outcomes assessed via validated questionnaires, but this is a stud
Bjornebekk
2023 · Neuroendocrinology
observational supports low High-dose androgen use was associated with reduced brain-derived neurotrophic factor, a biomarker linked to cognitive function.
Bjornebekk
2021 · Biol Psychiatry CNNI
observational supports moderate Prolonged AAS use was associated with accentuated (deviant) brain aging on MRI-based age prediction.
Tungesvik
2025 · Drug Alcohol Depend
observational mixed moderate Long-term AAS users showed altered cerebrovascular indicators versus non-using weightlifters, though cerebral blood flow findings were not uniformly impaired.
Bjornebekk
2017 · Biol Psychiatry
observational supports moderate Long-term AAS users showed thinner cortex and smaller subcortical volumes, a candidate neural substrate for cognitive deficits.
Coliță D et al
2025 · study_type: mechanism
observational supports low Human-focused narrative review of doping/AAS in elite athletes: cites behavioral and neuroimaging evidence that prolonged AAS use impairs visuospatial memory, executive functioning, and attentional control, linked to prefrontal-limbic alter
Kaufman
2024 · Am J Drug Alcohol Abuse
observational supports moderate Long-term supraphysiologic-dose AAS users showed poorer cognitive function than non-using weightlifters in middle age.
Zelleroth S et al
2024 · study_type: animal
animal supports moderate Animal (male rat) study comparing decanoate esters of nandrolone, testosterone, and trenbolone at supratherapeutic doses (15 mg/kg): only nandrolone decanoate caused impaired recognition memory on the novel-object-recognition test, indicati
Kanayama
2013 · Drug Alcohol Depend
observational mixed moderate Long-term AAS users showed deficits on visuospatial memory but performed comparably on several other cognitive measures.
Bjornebekk
2019 · Neuropsychology
observational supports moderate Long-term AAS-exposed weightlifters showed poorer cognitive performance with correlated structural brain differences versus non-exposed weightlifters.
Hauger
2019 · Addiction
observational mixed moderate AAS-dependent users showed greater structural brain differences than non-dependent users, consistent with dose/exposure-related brain effects.
Mhillaj
2015 · Front Neurosci
observational mixed low Animal/in-vitro work indicates supraphysiologic AAS can trigger neuronal apoptosis and reward-system changes, a mechanism for cognitive impairment.
Çınaroğlu M et al
2025 · study_type: observational
observational supports moderate Human observational study (n=285 gym-goers: 87 long-term PED/AAS users, 95 short-term, 103 non-users): long-term users showed significantly poorer Stroop interference (executive function) than short-term users/non-users, alongside higher de
Kaufman
2015 · Drug Alcohol Depend
observational supports moderate Long-term AAS users displayed cognitive dysfunction alongside brain abnormalities on imaging.

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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.