The influence of nutrition in nodular thyroid pathology: a systematic review

Nodular thyroid pathologies (NThyPs) are prevalent thyroid diseases, with a steadily increasing global incidence. Although their exact causes remain uncertain, various modifying factors, such as nutrition, influence their development. We aimed to systematically identify and synthesize the influence of dietary exposures on NThyPs risk. PubMed, Scopus, Web of Science, and EMBASE were searched on June 14, 2024, to identify relevant studies. Data extraction included study characteristics, sociodemographic factors, dietary intake assessments and exposures, and NThyPs subtypes. Out of 14,730 articles retrieved, 55 observational or experimental studies, in English, Spanish, or Portuguese, that assessed nutrition's impact on NThyPs were included, excluding non-human studies, reviews, meta-analyses, and publications outside the study's scope. Forty studies investigated how distinct dietary patterns, macronutrients, minerals, and vitamins contributed to or mitigated NThyPs development. Fish and seafood, vegetables and fruits, and meat were other dietary exposures investigated. In fourteen of previously selected studies, drink consumption was also addressed. This systematic review (CRD420234003439) suggests that reducing processed foods, sugars, meat, and dietary iodine lowers NThyPs risk, while coffee, tea, alcohol, and dairy products demonstrates potential protective roles. Fish and seafood, and fruits and vegetables also exhibit protective properties; nevertheless, further research is necessary to establish definitive conclusions.