Associations between food preferences, micronutrient insufficiency, and autonomic function in adolescents with a...

This study aimed to investigate the interrelationships between food preferences, micronutrient status, and autonomic function in adolescents with vasovagal syncope (VVS), exploring how dietary behaviour may contribute to syncope susceptibility.

We enrolled 138 adolescents with VVS and 78 age-matched healthy controls (13-17 years). Clinical assessment included syncope history, Modified Calgary Syncope Score (MCSS), and 24-h Holter monitoring for heart rate variability (HRV) analysis (SDANN, RMSSD, pNN50, TP, VLF, LF, HF, and LF/HF). Fasting serum levels of vitamins B6, B12, folate, and 25-hydroxyvitamin D (25(OH)D) were measured via ELISA. Food preferences were evaluated using a validated Ukrainian version of the Food Preference Questionnaire (FPQ) for adolescents and adults, covering vegetables, fruits, meat and fish, dairy, snacks, and starches. Data were analyzed using multiple linear regression, with assessment of FPQ reliability, construct, and discriminant validity.

Adolescents with VVS exhibited lower serum B6, B12, and 25(OH)D compared with controls, while folate levels were similar. HRV analysis demonstrated increased TP alongside elevated LF/HF ratios, suggesting altered autonomic regulation characterized by relative sympathetic predominance and reduced parasympathetic modulation at baseline. The FPQ demonstrated high reliability and validity. VVS participants reported lower preferences for vegetables, meat and fish, and starches (all FDR-corrected), with a trend toward lower fruit preference that did not survive correction. Regression analyses showed that higher vegetable preference was associated with increased folate and cobalamin, whereas meat and fish preference was positively associated with B6. Vegetable preference was negatively associated with HF, while meat and fish and dairy preferences were negatively associated with SDANN and RMSSD. Dairy preference showed a negative association with B6 and multiple HRV parameters, while snack and starch preference had modest or no associations. Food preferences were generally weakly related to syncope severity, with only starch preference showing a significant association with MCSS scores after FDR correction.

Adolescents with VVS exhibit distinct food preference patterns linked to micronutrient insufficiencies and altered HRV, suggesting an interaction between diet, nutrient status, and autonomic regulation. Integrating nutritional assessment and targeted interventions into clinical management may improve autonomic balance and reduce syncope burden. Future longitudinal and interventional studies are needed to clarify causal pathways and evaluate the efficacy of dietary and supplementation strategies in mitigating VVS episodes.