The Role of Diet in the Secondary Prevention of Myocardial Infarction, With a Focus on a Plant-Based Diet

This was a single-center, three-arm, controlled, partially randomized interventional pilot study designed to evaluate the feasibility and potential effects of dietary modification in the secondary prevention of myocardial infarction over a three-month period. Participants were recruited between January 2022 and December 2025. The study duration was three months.

Participants who agreed to change their dietary habits were randomized in a 1:1 ratio into two intervention groups using stratified block randomization according to diabetes mellitus status and smoking status. Group A followed a diet based on the recommendations of the European Society of Cardiology (ESC), while Group B adopted a strictly plant-based (vegan) diet.

Patients who declined dietary modification but agreed to undergo study assessments were included as a parallel, non-intervention control group (Group C), based on patient preference.

All participants underwent clinical and laboratory assessments at baseline and at three months, including body composition analysis using bioimpedance (InBody). In the intervention groups, additional scheduled visits were conducted at monthly intervals during the three-month period. At these visits, participants received nutritional counseling from a registered dietitian and completed a three-day dietary record to assess dietary intake and adherence. Participants were additionally allowed to contact the dietitian or the study physician outside the scheduled visits if needed.

Laboratory analyses included lipid profile (total cholesterol, LDL cholesterol, HDL cholesterol, lipoprotein(a), triglycerides), glycemic parameters (fasting blood glucose, glycated hemoglobin HbA1c), inflammatory markers (high-sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6)), vitamin B12, vitamin D, iron metabolism, complete blood count, and basic biochemical parameters.