At Elettra, we closely follow scientific developments that relate to the olive tree, its bioactive compounds, and their role in human health.
A new study from the Li Ka Shing Faculty of Medicine (HKUMed), University of Hong Kong, highlights something highly relevant to us: how fat quality in the diet affects the immune system’s ability to fight cancer — with oleic acid as the key protagonist.

What the study showed

The researchers examined γ-δ T lymphocytes (Vγ9Vδ2 cells), immune cells known for their tumor-killing capacity. They found that:
•oleic acid (OA) — the main monounsaturated fatty acid in olive oil — restores anti-tumor immunity in these cells when it is impaired
•palmitic acid (PA) — abundant in palm oil and ultra-processed foods — undermines their function

In a small clinical group of hepatocellular carcinoma patients receiving γ-δ T cell therapy (n=7), higher OA levels and lower PA levels in the blood correlated with better response — while the PA/OA ratio negatively associated with survival. This ratio is proposed as a potential prognostic indicator for γ-δ T-cell efficacy.

What is new mechanistically

The official Nature publication clarifies the intracellular mechanism:
•palmitic acid drives Vγ9Vδ2 cells to overproduce IFN-γ → which triggers pyroptosis (inflammatory cell death) → resulting in reduced anti-cancer activity
•oleic acid reduces this excessive IFN-γ output and attenuates pyroptosis → effectively restoring function

The study also shows that pharmacologic IFN-γ blockade or pyroptosis inhibition (e.g. dimethyl fumarate, DMF) can likewise rescue γ-δ T cell activity.

in plain terms: not all fats are the same — specific fatty acids “talk” to immune cells in different ways

What this means in practical diet context

This research does not state that food replaces medical treatment.
But it adds robust mechanistic evidence that:

choosing foods rich in oleic acid (e.g. extra virgin olive oil, avocado, some nuts)

and limiting foods rich in palmitic acid (palm oil, highly processed products, excessive fatty meats)

may help support the metabolic environment in which γ-δ T cells operate.
For patients under immunotherapy, this opens the path toward combined metabolic + clinical approaches — always under medical supervision.


Why this matters for Elettra


At Elettra, we do not view olive oil as “just a fat.”
We view it as a qualitative source of oleic acid within the Mediterranean dietary matrix.
These findings align with our commitment to scientifically informed production and responsible communication.

Quality matters.
Fat type matters.
And oleic acid — the “core” of olive oil — stands out again.

Important clarifications
•The study offers mechanistic & clinically relevant indications in a small patient sample — larger controlled studies are required.
•Any dietary intervention in patients under treatment must be done with the attending physician.

Sources
Official publication: Oleic acid restores the impaired antitumor immunity of γδ-T cells induced by palmitic acid, Signal Transduction and Targeted Therapy (Nature), 3 July 2025.