Research

Hormonal

Obesity-associated gut dysbiosis contributes to cognitive and mood deficits through the activation of the HPA-axis, leading to glucocorticoid overproduction, and the promotion of a pro-inflammatory milieu (endotoxemia/leaky gut) that causes neuro-inflammation.

If you are obese and experiencing brain fog or mood issues, your gut health may be a contributing factor, not just your weight. The paper suggests that improving diet (fiber, prebiotics) or using specific probiotics might help restore gut balance, reduce inflammation, and lower stress hormones, potentially improving cognitive and emotional health. This is not a cure-all, but a modifiable lever.

ModerateSupportsMEDIUM confidence
Experimental studies in animal models and, to a lesser extent, in humans suggest that the obesity-associated microbiota may contribute to the endocrine, neurochemical and inflammatory alterations underlying obesity and its comorbidities. These include dysregulation of the HPA-axis with overproduction of glucocorticoids, alterations in levels of neuroactive metabolites (e.g., neurotransmitters, short-chain fatty acids) and activation of a pro-inflammatory milieu that can cause neuro-inflammation.
Ana Agustí et al. · Frontiers in Neuroscience · 2018

Why this rating

The paper is a review citing animal models and limited human observational data; it explicitly notes human evidence is 'to a lesser extent'.

Source

Interplay Between the Gut-Brain Axis, Obesity and Cognitive Function

Ana Agustí et al. · Frontiers in Neuroscience · 2018

DOI 10.3389/fnins.2018.00155

narrative_reviewCited 295×
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DOI resolved against Crossref · corpus check 2026-06-10

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