title: Dietary evaluation of a low-iodine diet in Korean thyroid cancer patients preparing for radioactive iodine therapy in an iodine-rich region.
abstract: OBJECTIVE
  Despite the importance of a low-iodine diet (LID) for thyroid cancer patients preparing for radioactive iodine (RAI) therapy, few studies have evaluated dietary intake during LID. This study evaluated the amount of dietary iodine intake and its major food sources during a typical diet and during LID periods for thyroid cancer patients preparing for RAI therapy, and examined how the type of nutrition education of LID affects iodine intake.
  
  
  METHODS
  A total of 92 differentiated thyroid cancer patients with total thyroidectomy were enrolled from Seoul National University Hospital. All subjects completed three days of dietary records during usual and low-iodine diets before (131)I administration.
  
  
  RESULTS
  The median iodine intake was 290 µg/day on the usual diet and 63.2 µg/day on the LID. The major food groups during the usual diet were seaweed, salted vegetables, fish, milk, and dairy products and the consumption of these foods decreased significantly during LID. The mean energy intake on the LID was 1,325 kcal, which was 446 kcal lower than on the usual diet (1,771 kcal). By avoiding iodine, the intake of most other nutrients, including sodium, was significantly reduced during LID (P < 0.005). Regarding nutritional education, intensive education was more effective than a simple education at reducing iodine intake.
  
  
  CONCLUSIONS
  Iodine intake for thyroid cancer patients was significantly reduced during LID and was within the recommended amount. However, the intake of most other nutrients and calories was also reduced. Future studies are needed to develop a practical dietary protocol for a LID in Korean patients.
authors.affiliation: Department of Food Service and Nutrition Care, Seoul National University Hospital, Seoul, 03080, Korea.
authors.forename: Dal Lae
authors.initials: DL
authors.lastname: Ju
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, 03080, Korea.
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Park
authors.affiliation: Department of Food and Nutrition, Seoul National University, Seoul, 08826, Korea.
authors.forename: Hee-Young
authors.initials: HY
authors.lastname: Paik
authors.affiliation: Major of Food and Nutrition, School of Human Ecology, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi 14662, Korea.
authors.forename: Min-Ji
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital Biomedical Research Institute, Seoul, 03080, Korea.
authors.forename: Seonyeong
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Eulji University Hospital, Seoul, 01830, Korea.
authors.forename: Kyong Yeun
authors.initials: KY
authors.lastname: Jung
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, 03080, Korea.; Department of Internal Medicine, Thyroid Center, Samsung Medical Center, Seoul, 06351, Korea.
authors.forename: Tae Hyuk
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, 03080, Korea.; Department of Internal Medicine, Kangwon National University Hospital, Chuncheon, 24289, Korea.
authors.forename: Hun Sung
authors.initials: HS
authors.lastname: Choi
authors.affiliation: Major of Food and Nutrition, School of Human Ecology, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi 14662, Korea.
authors.forename: Yoon Ju
authors.initials: YJ
authors.lastname: Song
keywords: Low-iodine diet; dietary record; iodine intake; radioactive iodine therapy; thyroid cancer