Adherence to Mediterranean diet and prevalence of differentiated thyroid cancer: a single-center Unit of Thyroid Surgery experience in a Southern-Italy cohort.

Background: The Mediterranean diet (MD) is recognized as a cultural heritage by UNESCO, thus, is a nutritional model widely spread in all Mediterranean countries. As already demonstrated by several studies, high adherence to MD is a protective factor against many chronic diseases. Conversely, poor adherence to the diet is correlated with an increased prevalence of these pathologies. The aim of the current study was to investigate the relationship between the adherence to MD and the prevalence of benign and malignant thyroid disease.

Methods: We analyzed the health status of 60 patients, referred to total thyroidectomy and histological examination, due to nodular thyroid disease. Eating habits were evaluated according to the PREDIMED questionnaire, and patients' results were evaluated according to histological findings of benign or malignant disease.

Results: PREDIMED Score was lower in patients with malignant thyroid disease (MTD) than those with benign thyroid disease (BTD) (5.27±0.87 vs. 7.00±1.23, respectively; P value <0.001). A significant correlation was found between poor adherence to MD and diagnosis of MTD (r=0.454; P<0.001). Excessive consumption of butter and sugary drinks, along with low consumption of pasta, white meat, and rice were found to be predictive factors of MTD.

Conclusions: In our cohort, a PREDIMED Score ≤7 resulted significantly related to MTD diagnosis, while a good adherence to MD resulted associated with BTD. Moreover, high consumption of sweetened beverages seemed to predict MTD histologic diagnosis, while, conversely, low consumption resulted predictor of BTD. Nevertheless, more studies are needed to evaluate the effective impact of MD on MTD incidence on larger cohorts.