MedQA_jp

子どもでは、昆布過食など食餌による過剰なヨード(ヨウ素)摂取は甲状腺機能障害や甲状腺腫に関連します。北海道では、“endemic coastal goiter”in Hokkaido とよばれる病気が知られています。ヨード(ヨウ素)の豊富な海草の多い地域の伝統食が関係します。尿中ヨード(ヨウ素)濃度で500 mcg/L以上であると、甲状腺に影響し大きくなります（甲状腺腫）。
Zimmermann MB 2005 / 風土病について Suzuki H 1965

原著 “ENDEMIC COAST GOITRE”
　http://www.eje-online.org/cgi/content/abstract/50/2/161
Acta Endocrinologica, Vol 50, Issue 2, 161-176, 1965
European Society of Endocrinology
ENDEMIC COAST GOITRE IN HOKKAIDO, JAPAN
Hoji Suzuki, Tadashi Higuchi, Kunio Sawa, Sachiya Ohtaki and Yoshihiko Horiuchi

A survey of goitre was made in the goitrous regions on the coast of Hokkaido, the northern island of Japan. Prevalence of goitre was confirmed in Hidaka coast and Rishiri Island. All goitrous patients were clinically euthyroid. The usual diet of the inhabitants of these districts consisted of a large quantity of iodine-rich seaweeds. Urinary excretion of iodine in five patients exceeded 20 mg per day.

中略

In a few patients restriction of seaweed induced a marked decrease in the size of goitre. The major cause of the endemic coast goitre seems to be excessive and longstanding intake of iodine from seaweed, and the similarities of iodine metabolism between the endemic coast goitre and iodide goitre arc discussed.

American Journal of Clinical Nutrition, Vol. 81, No. 4, 840-844, April 2005
American Society for Clinical Nutrition
High thyroid volume in children with excess dietary iodine intakes
Michael B Zimmermann, Yoshiya Ito, Sonja Y Hess, Kenji Fujieda and Luciano Molinari

Conclusions: Chronic iodine intakes approximately twice those recommended – indicated by UI concentrations in the range of 300–500 mcg/L – do not increase Tvol in children. However, UI concentrations >=500 mcg/L are associated with increasing Tvol, which reflects the adverse effects of chronic iodine excess.

他の参照ページ：
こども健康倶楽部 – 先天性甲状腺機能低下症（クレチン症）の患者さんとご家族のための情報サイト
　PDFファイル：昆布過食による”Endemic Coast Goitre” 原著の写真コピーがあります。
　http://kodomo-kenkou.com/default/file_download/58