Background <p>This study aimed to assess the feasibility of the protocol, including recruitment rate, intervention adherence, dropout rate, the occurrence of adverse effects and feedback from participants. This study also sought to evaluate the effects of two interventions—MIND + FB (Mediterranean-DASH Intervention for Neurodegenerative Delay diet combined with forest bathing) and MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay diet only)—on clinical outcomes, including cognitive function, metabolic health markers, and adherence to the MIND diet, both immediately post-intervention and three months post-intervention. It was hypothesized that both intervention groups would show significant within-group improvements in outcomes, while the control group would not.</p> Methods <p>A three-parallel-group, single-blinded randomized controlled trial was conducted with 48 participants (aged ≥ 60 years) randomized into MIND + FB (<i>n</i> = 16), MIND (<i>n</i> = 16), and control (<i>n </i>= 16) groups. The outcome assessor was blinded, while the participants and interventionist were not blinded to the group assignment. The MIND + FB group received eight sessions over three months (four nutritional counseling and four forest therapy sessions), the MIND group received four nutritional counseling sessions, and the control group received usual care. Data were collected at baseline (T0), immediately post-intervention (T1), and three months post-intervention (T2). The primary aim was to test the feasibility of the study. The secondary outcomes included cognitive function, metabolic health markers and MIND diet adherence.</p> Results <p>The recruitment rate was 60%, with high adherence (MIND: 97%, MIND + FB: 95%) and a 4.2% dropout rate. No significant adverse effects were reported. Both MIND + FB and MIND groups showed significant within-group improvements in cognitive function with a larger effect size in MIND + FB (Kendall’s W = 0.619). The MIND + FB group also demonstrated significant reductions in fasting blood glucose (Kendall’s W = 0.279)) and waist circumference (Kendall’s W = 0.382)). Improved MIND diet adherence was observed in the MIND group (Kendall’s W = 0.256). Between-group comparisons showed significant cognitive function improvements in both intervention groups versus control.</p> Conclusions <p>The MIND + FB intervention may enhance cognitive function and metabolic health in older adults with hypertension, potentially offering greater benefits than the MIND diet alone. While MIND alone promotes better diet adherence, the dose-response effects on health outcomes remain unclear. Future studies should refine behavioural strategies to enhance adherence and identify the most effective components. A larger trial is recommended to confirm these findings and address current study limitations.</p> Trial registration <p>ClinialTrials.gov registration number: NCT05342896. Registered on 3rd Jan 2021. <a href="https://clinicaltrials.gov/study/NCT05342896">https://clinicaltrials.gov/study/NCT05342896</a>.</p>