Objectives: This study aimed to evaluate the association between adherence to the Mediterranean diet and blood trimethylamine-N-oxide (TMAO) levels. Methods: This randomized clinical trial enrolled 53 healthy adults with normal or overweight body mass index (BMI) who were recruited from a cardiology outpatient clinic in Istanbul, Turkey. Dietary patterns and Mediterranean diet adherence (assessed using the MEDAS) were evaluated alongside anthropometric and biochemical parameters, including fasting glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Twenty individuals with low adherence underwent a 4-week Mediterranean dietary intervention with daily dietary monitoring. To assess changes, pre- and postintervention data were compared. Results: The results revealed that individuals adhering to the Mediterranean diet exhibited significantly lower blood TMAO levels (p 0.05). In females, only blood TMAO levels exhibited significant reduction, with no other biochemical parameters indicating significant differences (p > 0.05). Additionally, males demonstrated significant improvements in anthropometric measures, including weight, BMI, fat mass, muscle mass, waist, and hip circumference, compared with pre-intervention values (p 0.05). Conclusions: Our findings demonstrate that implementing the Mediterranean diet in individuals with initially low adherence causes significantly reduced blood TMAO levels even within a short intervention period of 4 weeks.
Deniz et al. (2025) studied this question.