Mediterranean diet and Alzheimer's protection

Brain. The GeroScience 2025 meta-analysis shows a 30% reduction in Alzheimer's risk and 11% for all-cause dementia among Mediterranean diet adherents.

The two hallmark lesions of Alzheimer's appear 15 to 20 years before symptoms : extracellular beta-amyloid (Aβ) plaques and intraneuronal hyperphosphorylated Tau protein.

- OLEOCANTHAL (extra virgin olive oil) : inhibits COX-1 and COX-2 like ibuprofen, increases P-glycoprotein (P-gp) and LRP1 expression at the blood-brain barrier, raising Aβ clearance from 62% to 79.9%. It also inhibits Tau fibrillisation and activates the degrading enzymes IDE and NEP.

- OLEUROPEIN : another olive polyphenol, activates autophagy and reduces mitochondrial oxidative stress.

- DHA : makes up 15 to 20% of neuronal membrane fatty acids. Its deficiency increases Aβ production.

- NF-kB activated in microglia is central to Alzheimer's neuroinflammation; polyphenols inhibit it.

- SIRT1 inhibits BACE1 (reducing Aβ production) and lowers Tau phosphorylation.

- Nrf2 and NF-kB are antagonists : activating Nrf2 simultaneously inhibits NF-kB.

- Glymphatic system : clears Aβ during deep sleep.

- Elevated homocysteine accelerates brain atrophy; the Oxford VITACOG study showed that B vitamins (B6, B9, B12) slow this atrophy.

ApoE e4 carriers benefit most from a triple-target approach : LDL, inflammation and homocysteine.

Scientific references : PMID 39797935, 23414128, 26348065, 39349103.