EVOO

[Plumster]

I would be surprised if this mouse study hasn't been added here, but my search yielded no results:
"Extra virgin olive oil improves synaptic activity, short‐term plasticity, memory, and neuropathology in a tauopathy model," published in Aging Cell.

Abstract
In recent years, increasing evidence has accumulated supporting the health benefits of extra virgin olive oil (EVOO). Previous studies showed that EVOO supplementation improves Alzheimer's disease (AD)‐like amyloidotic phenotype of transgenic mice. However, while much attention has been focused on EVOO‐mediated modulation of Aβ processing, its direct influence on tau metabolism in vivo and synaptic function is still poorly characterized. In this study, we investigated the effect of chronic supplementation of EVOO on the phenotype of a relevant mouse model of tauopathy, human transgenic tau mice (hTau). Starting at 6 months of age, hTau mice were fed chow diet supplemented with EVOO or vehicle for additional 6 months, and then the effect on their phenotype was assessed. At the end of the treatment, compared with control mice receiving EVOO displayed improved memory and cognition which was associated with increased basal synaptic activity and short‐term plasticity. This effect was accompanied by an upregulation of complexin 1, a key presynaptic protein. Moreover, EVOO treatment resulted in a significant reduction of tau oligomers and phosphorylated tau at specific epitopes. Our findings demonstrate that EVOO directly improves synaptic activity, short‐term plasticity, and memory while decreasing tau neuropathology in the hTau mice. These results strengthen the healthy benefits of EVOO and further support the therapeutic potential of this natural product not only for AD but also for primary tauopathies.

https://onlinelibrary.wiley.com/doi/ful ... acel.13076

[NF52]

..."Extra virgin olive oil improves synaptic activity, short‐term plasticity, memory, and neuropathology in a tauopathy model," published in Aging Cell.

Abstract...In this study, we investigated the effect of chronic supplementation of EVOO on the phenotype of a relevant mouse model of tauopathy, human transgenic tau mice (hTau)...Our findings demonstrate that EVOO directly improves synaptic activity, short‐term plasticity, and memory while decreasing tau neuropathology in the hTau mice. These results strengthen the healthy benefits of EVOO and further support the therapeutic potential of this natural product not only for AD but also for primary tauopathies.

https://onlinelibrary.wiley.com/doi/ful ... acel.13076

Thanks for sharing this, Plumster!
I went to the source and skimmed the article, which includes a list of human trials showing benefits of EVOO.

The PREDIMED‐NAVARRA randomized clinical trial involving a cohort of 268 subjects (74.1 ± 5.7 years old) showed that long‐term intervention with an EVOO‐rich Mediterranean diet (6.5 years) results in better cognitive performances, especially across fluency and memory tasks, and less MCI incidence as compared to controls (Martinez‐Lapiscina et al., 2013). Moreover, looking specifically at progression of well‐established AD biomarkers, including β‐amyloid deposition, glucose metabolism, and neuronal loss, a more recent longitudinal study confirmed that, in middle‐aged adults, strong adherence to the Mediterranean diet (MeDi) provide significant protection against AD (Valls‐Pedret et al., 2015). Consistently, another randomized clinical trial showed that in an older population Mediterranean diet supplemented with EVOO (1 L/week) was associated with improved cognitive function after 4.1 years follow‐up (Berti et al., 2018).

This article seems to describe a clear mechanism for action in the hippocampus synapses as the reason for that.

...our data are in agreement with studies showing that oleuropein, one of the main components of EVOO, facilitates hippocampal synaptic activity and long‐term plasticity...Remarkably, tau pathology strictly correlates with the severity of dementia (Arriagada, Growdon, Hedley‐Whyte, & Hyman, 1992; Riley, Snowdon, & Markesbery, 2002)...Collectively, our findings ...provide strong preclinical evidence in support of the novel concept that EVOO should be considered as a potential and viable multi‐targeting agent not only for AD but also for primary tauopathies.

[Emphasis added.]

All good news, including for those mice, who for a few months enjoyed EVOO-infused mice chow, living la dolce vita!