OleoMetS: the first study to evaluate the effects of Thousand Olives® in individuals with Metabolic Syndrome

A major scientific milestone for the Greek nutraceutical sector is marked by the publication of the OleoMetS clinical study in Clinical Nutrition ESPEN, the official journal of the European Society for Clinical Nutrition and Metabolism (ESPEN).

The OleoMetS study is pioneering in nature, as it is the first randomized, double-blind, placebo-controlled clinical trial worldwide to directly evaluate the beneficial effects of purified olive oil polyphenols (OOPs) as a dietary supplement in individuals with Metabolic Syndrome, offering new, robust clinical evidence of their effectiveness.

The aldehydic phenolic compounds of olive oil (OOPs), including oleocanthal, oleacein, oleuropein aglycone, ligstroside aglycone, tyrosol, and hydroxytyrosol, are highly bioactive secoiridoids with unique health-protective properties. Preclinical studies have demonstrated that OOPs exhibit anti-inflammatory and antioxidant activities. The aim of the OleoMetS study was to evaluate the direct health effects of OOPs, administered as a dietary supplement, in individuals diagnosed with Metabolic Syndrome.

A total of 102 individuals diagnosed with Metabolic Syndrome participated in the study, ensuring robust and reliable results through a randomized, double-blind, placebo-controlled clinical trial design. The 12-week intervention provided either a dietary supplement containing a polyphenol-rich olive oil extract at a dose of 10 mg/day (80% oleocanthal/oleacein, 18% oleuropein aglycone/ligstroside aglycone) or a placebo. No lifestyle modifications were recommended, and dietary intake and physical activity were assessed at week 6.

Key Findings of the OleoMetS Study

Clinically proven reduction in blood glucose:
The OleoMetS trial demonstrated a significant reduction in fasting glucose (7.06mg/dL) and HbA1c (–0.29%), confirming a meaningful benefit in glycaemic control.

Holistic metabolic improvement:
Beyond glucose regulation, supplementation with OOPs led to 5–7% improvements in additional key metabolic markers, including reductions in Body Mass Index (–1.15), systolic blood pressure (–7.66 mmHg), triglycerides (–8.57 mg/dL), and oxidized LDL (–5.01).

Improved quality of life:
Participants reported a 25% improvement in fatigue-related scores (–16.88 points), indicating a positive impact on overall wellbeing and daily energy levels.

Equivalent to high-quality olive oil intake:
A daily intake of 10 mg of OOPs polyphenols is equivalent to approximately three tablespoons of high-quality extra virgin olive oil, in line with EFSA recommendations, with enhanced bioavailability compared to olive oil consumption.

Safe and well tolerated:
The intervention was well tolerated, with no serious adverse events, confirming the supplement’s excellent safety profile.

Scientifically engineered product:
The product Thousand Olives® contains a precisely defined combination of highly bioactive secoiridoids, including oleocanthal and oleacein, extracted and formulated using an innovative and cost-effective patented method.

High-Level International Research Collaboration

The study represents a flagship collaboration between leading academic institutions. The research team included scientists from the University of Nicosia Medical School (Cyprus), the Yale School of Public Health (USA), the Faculty of Pharmacy of the National and Kapodistrian University of Athens (Greece), and the Apostolos Loukas Medical Center. This collaboration underscores the international scope and scientific rigor applied to the evaluation of olive oil polyphenols.

Study Authors and Institutional Affiliations

The OleoMetS study was authored by:
George Samoutis a,*, Tassos C. Kyriakides b, Nicholas Demetriou c, Evdoxia Poulianiti c, Gregoria Samouti c, Sophronia Samouti c, Panagiotis Diamantakos d, Eleni Melliou d, Prokopios Magiatis d,**

a University of Nicosia Medical School, Cyprus
b Yale School of Public Health, New Haven, CT, USA
c Apostolos Loukas Medical Centre, Nicosia, Cyprus
d Laboratory of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, University Campus 15771, Zografou, Greece

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Read the OleoMetS study here or scan the QR code: