ABSTRACT
Background Adhering to a Mediterranean Diet (MedDiet) is associated with a healthier cardiometabolic profile. However, there are limited studies on the MedDiet benefits for non-Mediterranean racial/ethnic minorities, for whom this diet may be unfamiliar and inaccessible and who have a high risk of chronic diseases. Objective To describe the study design of a pilot trial testing the efficacy of a MedDiet-like tailored to adults in Puerto Rico (PR). Methods The Puerto Rican Optimized Mediterranean-like Diet (PROMED) was a single-site four-month parallel two-arm randomized pilot trial among a projected 50 free-living adults (25-65y) living in PR with at least two cardiometabolic risk factors (clinicaltrials.gov registration #NCT03975556). The intervention group received one individual nutritional counseling session on a portion-control culturally-tailored MedDiet. Daily text messages reinforced the counseling content for two months, and we supplied legumes and vegetable oils. Participants in the control group received cooking utensils and one standard portion-control nutritional counseling session that was reinforced with daily texts for two months. Text messages for each group were repeated for two more months. Outcome measures were assessed at baseline, 2 months, and 4 months. The primary outcome was a composite cardiometabolic improvement score;secondary outcomes included individual cardiometabolic factors;dietary intake, behaviors, and satisfaction;psychosocial factors;and the gut microbiome. Results PROMED was designed to be culturally appropriate, acceptable, accessible, and feasible for adults in PR. Strengths of the study include applying deep-structure cultural components, easing structural barriers, and representing a real-life setting. Limitations include difficulty with blinding and with monitoring adherence, and reduced timing and sample size. The COVID-19 pandemic influenced implementation, warranting replication. Conclusions If PROMED is proven efficacious in improving cardiometabolic health and diet quality, the findings would strengthen the evidence on the healthfulness of a culturally-appropriate MedDiet and support its wider implementation in clinical and population-wide disease-prevention programs.