Influência dos padrões alimentares no risco de câncer de tireoide: uma revisão sistemática

Abstract

The worldwide incidence of thyroid cancer (TC) has been rising, and this continuous increase cannot be attributed only to more meticulous detection of thyroid nodules and accurate diagnostic techniques. Interactions among nutrition and lifestyle may contribute to TC risk. Studies suggest a possible relationship between dietary patterns and TC risk, the current evidence remains inconclusive. Therefore, a deeper understanding of the biological mechanisms linking dietary patterns to TC risk could contribute to the identification of modifiable risk factors. This dissertation aimed to investigate the association between dietary patterns and TC risk through a systematic review of the available evidence; it was conducted between September 2023 and January 2025. To achieve this, the PubMed/Medline, Embase, Scopus, Web of Science, and LILACS databases were searched without restrictions on language or publication years. Three independent reviewers participated in the selection and data extraction from original publications of observational studies. The Newcastle-Ottawa Scale (NOS) was used to assess the risk of bias, with most studies demonstrating excellent quality. A total of 45 studies were included–2 cross-sectional, 13 cohort, and 30 case-control studies. Of these, 40 examined the association of a posteriori dietary patterns with TC risk, while 5 analyzed a priori patterns. Significant findings for a posteriori dietary pattern showed that diets high in plant-based foods, fruits, fish, lowfat meats, dairy, and unsaturated fats were linked to a lower risk of TC. In contrast, high consumption of starchy foods, seafood, seaweed, processed meats, instant foods, fast food, and adherence to a Western dietary pattern increased the risk of TC. Regarding a priori dietary patterns, a diet with a higher inflammatory potential was positively associated with TC risk. In summary, while important links exist between diet, the environment, metabolism, and thyroid carcinogenesis, more robust studies with rigorous control of confounding variables and more homogeneous samples are needed for a complete elucidation of these mechanisms.