Abstract: Background: Aging is an important risk factor for cardiovascular diseases and con-vincing data has shown that chronic low-grade inflammation, which develops with advanced age, contributes significantly to cardiovascular risk. Objectives: The present study aimed to use ¹⁸F-FDG/¹⁸F-NaF-PET/CT imaging to respectively gauge arterial inflammation and microcalcifi-cation in healthy elderly and to assess the potential benefits of a tyrosol- and hydroxytyrosol-rich diet on these two markers of atherosclerotic plaque fragility. Methods: Eleven healthy partici-pants (mean age 75 ± 5.67 years) were supplemented for 6 months with high polyphenol-rich extra virgin olive oil (HP-EVOO), extra virgin olive oil (EVOO), or refined olive oil (ROO). The partic-ipants underwent PET/CT imaging with ¹⁸F-FDG and ¹⁸F-NaF radiotracers at baseline and after 6 months. ¹⁸F-FDG and ¹⁸F-NaF uptakes were quantified using standardized uptake values (SUV) and were categorized based on artery calcification and olive oil type. Results: A total of 324 slices of the aortas of the imaged participants were analyzed for arterial inflammation and 327 slices were analyzed for microcalcification. 18F-FDG uptake was significantly higher in the non-calcified segments than in the calcified segments (SUVmax = 2.70 0.62 and SUVmax = 2.54 0.44, respectively, p<0.042). Conversely, the non-calcified segments displayed significantly lower 18F-NaF uptake than the calcified segments (SUVmax = 1.90 0.37 and 2.09 0.24, respec-tively, p<0.0001). The 6-month supplementation with HP-EVOO induced a significant reduction in 18F-FDG uptake in both the non-calcified (2.93 0.23 to 2.75 0.38, p<0.004) and calcified seg-ments of the aortas (2.25 0.29 to 2.15 0.19, p<0.02). 18F-NaF uptake was also significantly low-er in patients supplemented with HP-EVOO (SUVmax = 1.98 0.33 at baseline compared to 1.85 0.28, after the 6-month supplementation, p<0.004), whereas no significant effect was observed with EVOO. Conversely, participants supplemented with ROO displayed a significant increase in 18F-NaF uptake (SUVmax = 1.78 0.34 to 1.95 0.34, p<0.0001). Conclusion: The present study confirmed that ¹⁸F-FDG/¹⁸F-NaF-PET/CT imaging is a valuable approach for assessing age-related arterial damage and demonstrated that a phenolic compound-rich diet reduces both arterial inflammation and atherosclerotic lesion microcalcification.