Planetary Health Diet, gut–liver–brain axis, MASLD and cognitive aging: a narrative review
A narrative review reports that large observational cohorts link higher adherence to the Planetary Health Diet with lower MASLD prevalence and severity and slower cognitive decline; mechanistic pathways remain proposed, and randomized trials are still needed. [1]
Automatic summary · not editorially reviewed
The key findings
The review frames MASLD and cognitive aging as interrelated conditions sharing gut-derived mechanisms and asks whether the Planetary Health Diet could support liver and brain health via the gut–liver–brain axis. [1]
Large observational cohorts link higher PHD adherence to lower MASLD prevalence and severity, slower cognitive decline, reduced dementia incidence and more favorable Alzheimer's neuropathology. [1]
The authors describe the evidence as predominantly observational and propose future randomized controlled trials with liver imaging, cognitive assessment, microbiome profiling and culturally adapted dietary interventions. [1]
The source at a glance
- Study type / format
- Structured narrative literature review (abstract)
- Population / context
- People in large observational cohorts and patients with MASLD or cognitive aging discussed in the reviewed literature
- Summary based on
- Study abstract
- Original publication
- October 5, 2026
Review question: diet, gut–liver–brain axis, liver and cognition
The authors describe MASLD and cognitive aging as common, interrelated conditions that share mechanisms originating in the gut. They ask whether the Planetary Health Diet (PHD), a sustainable plant-forward framework proposed by the EAT-Lancet Commission, might support both liver and brain health through the gut–liver–brain axis. This is a framing question in a narrative review, not a tested hypothesis in a trial.
Supporting source [1]
Observational cohort links to MASLD and cognitive outcomes
The review reports that epidemiological evidence from large cohorts links higher PHD adherence to lower MASLD prevalence and severity, slower cognitive decline, reduced dementia incidence and more favorable Alzheimer's disease neuropathology. These are associations from observational data, not proof that the diet causes these outcomes. The abstract gives no effect sizes, cohort sizes or follow-up durations.
Supporting source [1]
Proposed mechanisms and the need for randomized trials
Mechanistically, the review states that PHD components may change gut microbiota composition and diversity, increase short-chain fatty acid production, regulate bile acid signaling through the farnesoid X receptor (FXR) and Takeda G-protein-coupled receptor 5 (TGR5), strengthen the intestinal barrier and reduce metabolic endotoxemia and neuroinflammation. The authors call current evidence predominantly observational and propose future randomized controlled trials combining liver imaging, cognitive assessment, microbiome profiling and culturally adapted dietary interventions.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. This is a structured narrative review, not a systematic review or trial. The reported cohort links are associations, and the mechanistic pathways are described as possible, not established. No effect sizes, sample sizes or follow-up periods are given.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Cai H, Chen C, Cai H, Zhang D, Huang Q. · europepmc.org · October 5, 2026