This week on the Olive Health Information System website
The newsletter of the University of Navarra and the IOC dedicated to health
The Mediterranean diet (MedDiet), particularly when enriched with extra virgin olive oil (EVOO), has been consistently associated with cardiovascular and metabolic health benefits. Beyond its favourable monounsaturated fatty acid profile, EVOO naturally contains bioactive phenolic compounds, such as hydroxytyrosol and tyrosol, which may contribute to these effects through antioxidant and anti-inflammatory mechanisms.
Given the central role of diet in the prevention and management of metabolic diseases such as type 2 diabetes, understanding the contribution of these bioactive compounds may help explain some of the health benefits attributed to the Mediterranean dietary pattern. However, the extent to which differences in the phenolic content of olive oil translate into measurable metabolic benefits remains insufficiently understood.
This study therefore investigated whether phenolic-rich EVOO could provide additional benefits compared with regular olive oil in 28 healthy young adults, who consumed each oil for four weeks in a crossover design.
Consumption of phenolic-rich EVOO resulted in substantially higher urinary levels of hydroxytyrosol- and tyrosol-derived metabolites, confirming greater exposure to these compounds. Interestingly, in exploratory analyses, phenolic-rich EVOO consumption was also associated with a small reduction in waist circumference and HbA1c, while greater levels of hydroxytyrosol-derived metabolites tended to be associated with greater improvements in these markers.
Although these metabolic findings are preliminary and hypothesis-generating, their direction is encouraging and provides a rationale for further investigating whether EVOO phenolic compounds contribute to improved glycaemic and metabolic health.
While the previous study explored whether bioactive phenolic compounds in EVOO may contribute to metabolic health, the potential benefits of the MedDiet may extend beyond individual metabolic outcomes.
This cross-sectional study investigated the relationship between adherence to the MedDiet, smoking, and epigenetic age acceleration in 928 participants from the Airwave Health Monitoring Study.
The researchers used several “epigenetic clocks”—tools that estimate biological ageing by analysing chemical changes in DNA—to assess whether participants appeared biologically younger or older than expected for their chronological age.
Greater adherence to the MedDiet was associated with lower epigenetic age acceleration in some of these measures, suggesting a slower biological ageing profile. Smoking, in contrast, was strongly associated with accelerated epigenetic ageing. Interestingly, among current smokers, smoking-related age acceleration was lower in participants with greater adherence to the MedDiet, with fruits, vegetables, and whole grains showing the most consistent associations.
These findings suggest that dietary patterns may influence molecular markers of biological ageing and may be associated with differences in the biological impact of smoking. However, given the cross-sectional nature of the study, these results demonstrate associations rather than causality and do not imply that a healthy diet can offset the harmful effects of smoking.
Other articles mentioned this week in the OHIS newsletter:
Olive oil
Aging
Basic research
Cardiovascular disease
Dietary pattern
Towards an Optimal Diet for Health in Asia: The Asian-Mediterranean Dietary Pattern.
Gut health
Hepatic disease
Cancer

