- Source type
- Study
- Access type
- Full text
- Publisher
- PubMed Central
- Date
- 2025
- Added
- 2026-07-04
Trust profile
VV Source Trust Matrix v1.0
VV Source Trust Matrix v1.0 asks whether this source is trustworthy for the claim lane being used, not whether every possible claim from it is equally strong.
91
Government health research
- Publisher type
- Government research
- Bias profile
- Low
This source is strongest for safety and clinical outcomes and weaker for consumer context and regulatory status.
VV Source Fit Score 1.0
Fit by use case
Fit scores are role-specific. A source can be excellent for one claim lane and weak for another.
- Regulatory status
- 66/100
- Context Source
- Clinical outcomes
- 90/100
- Primary Anchor
- Mechanism
- 90/100
- Primary Anchor
- Safety
- 92/100
- Primary Anchor
- Consumer context
- 88/100
- Strong Support
- Trial discovery
- 89/100
- Strong Support
Best used for
- Research synthesis
- Public-health context
- Safety resources
Weak for
- Primary endpoint extraction when a study is available
Used in Viral Vitalism
Does Cannabis Shrink Your Brain?
Roles: Primary source
Lifetime Cannabis Use Is Associated with Brain Volume and Cognitive Function in Middle-Aged and Older Adults
Roles: Primary source
Show section-level references
Claim ledger
Claims supported
Reviewed claim cards that cite this source in the evidence graph.
cannabis: The broad claim that cannabis shrinks your brain overstates
The broad claim that cannabis shrinks your brain overstates a mixed evidence base and swaps endpoints such as perfusion, activation, volume, and cognition.
cannabis: Older-adult cannabis brain-volume counter-signals break the simple shrinkage meme
Older-adult cannabis brain-volume counter-signals break the simple shrinkage meme but do not prove cannabis protects the aging brain.
Related studies
Related sources
Lifetime Cannabis Use Is Associated with Brain Volume and Cognitive Function in Middle-Aged and Older Adults
Counter-signal source. Observational UK Biobank analysis; do not convert into neuroprotection proof.
- Trust score
- 91
- Publisher
- PubMed
- Indexed by
- PubMed
- Access
- Abstract/index
- Usage
- 7 connections
What are marijuana's long-term effects on the brain?
Government consumer-health context for long-term brain-effect framing and adolescent exposure cautions.
- Trust score
- 91
- Publisher
- National Institute on Drug Abuse
- Access
- Official
- Usage
- 5 connections
Dave Asprey Facebook post: cannabis brain shrinkage claim
Public-discourse source documenting the Facebook version of the claim. Use for claim-accountability context only, not as clinical evidence.
- Trust score
- 60
- Publisher
- Access
- Publisher
- Usage
- 4 connections
Dave Asprey X post: marijuana shrinks your brain
Public-discourse source documenting the viral claim. Use for claim-accountability context only, not as clinical evidence.
- Trust score
- 60
- Publisher
- X
- Access
- Publisher
- Usage
- 4 connections
Sanofi: Cenrifki approved in the EU for secondary progressive multiple sclerosis without relapses
Canonicalized from rapid brief sanofi-cenrifki-tolebrutinib-eu-spms-approval.
- Trust score
- 60
- Publisher
- Sanofi
- Access
- Publisher
- Usage
- 1 connection
Wall Street Journal: Sanofi Multiple Sclerosis Drug Gets EU Approval
Canonicalized from rapid brief sanofi-cenrifki-tolebrutinib-eu-spms-approval.
- Trust score
- 60
- Publisher
- Wall Street Journal
- Access
- Publisher
- Usage
- 1 connection