Evidence map›Paper›PMID 40892726›Full record

ArticlePloS one2025

A quantitative projection of the net health effects of cannabis legalization in Germany.

Afschin Gandjour

Abstract read
In one paragraph

Article in PloS one, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
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1 · What the graph read from it

What it found

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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

1 author.

Afschin GandjourFrankfurt School of Finance & Management, Frankfurt, Germany.ORCID https://orcid.org/0000-0002-4262-8344

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

BACKGROUND/

aimCannabis consumption in Germany has been on the rise, culminating in the legalization of recreational cannabis in 2024. This shift aims to minimize the harms associated with black-market cannabis, such as exposure to contaminants, while regulating consumption to reduce health risks. The primary aim of this study is to quantitatively assess the net health effects of cannabis legalization in Germany by balancing harm reduction from fewer contaminants against potential risks from increased consumption.

methodsA quantitative projection model was employed to evaluate the potential net health effects of cannabis legalization in Germany. By estimating the likely increase in consumption and corresponding health risks, the study calculated quality-adjusted life year (QALY) losses due to cannabis use disorder (CUD) and long-term health impacts from both cannabis dependence and contamination exposure.

resultsProjected increases in adult cannabis consumption may lead to 400,000-800,000 new users, resulting in approximately 2,300 additional cases of severe long-term mental health conditions. The corresponding QALY losses from CUD-related harms are estimated to be approximately nineteen times greater than the health gains from reduced contamination-related harm. Sensitivity analysis shows that consumption rates have a strong influence on net QALY outcomes, with even a 1% increase in cannabis use sufficient to produce net population-level harm.

conclusionsThe findings suggest that cannabis legalization in Germany may not achieve the intended health benefits. Increased consumption, particularly among new users, may result in considerable public health burdens, with QALY losses associated with CUD outweighing gains from reduced contamination. Effective regulation and public health interventions are needed to minimize adverse health outcomes while avoiding a resurgence of black-market sales.

Indexed as

CannabisLegislation, DrugMarijuana AbuseMarijuana SmokingAdultFemaleGermanyHumansMaleQuality-Adjusted Life Years

Identifiers

PMID40892726
PMCPMC12404361

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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.