Editing Hashimoto's thyroiditis (section)

=== Geographic influence of dietary trends ===
Geography plays a large role in which regions have access to diets with low or high iodine. Iodine levels in both water and salt should be heavily monitored in order to protect at-risk populations from developing hypothyroidism.<ref>{{cite journal | vauthors = Katagiri R, Yuan X, Kobayashi S, Sasaki S | title = Effect of excess iodine intake on thyroid diseases in different populations: A systematic review and meta-analyses including observational studies | journal = PLOS ONE | volume = 12 | issue = 3 | pages = e0173722 | date = 2017-03-10 | pmid = 28282437 | pmc = 5345857 | doi = 10.1371/journal.pone.0173722 | bibcode = 2017PLoSO..1273722K | doi-access = free }}</ref> Geographic trends of hypothyroidism vary across the world as different places have different ways of defining disease and reporting cases. Populations that are spread out or defined poorly may skew data in unexpected ways.<ref name="Chistiakov-2005" />