Knowledge, Self-Efficacy, and Perceived Barriers on the Low-Iodine Diet among Thyroid Cancer Patients Preparing for Radioactive Iodine Therapy

The purposes of the study were to assess knowledge, self-efficacy, and perceived barriers on a low-iodine diet among thyroid cancer patients and to identify strategies for nutrition education. A self-administered questionnaire was developed based on a review of literature and pilot-tested. A total of 121 female thyroid cancer patients participated in a survey and 117 responses were used for data analysis. An average knowledge score of the thyroid cancer patients was 4.5 point (available score: 0-10 point). Majority of the respondents knew that seaweeds such as lavers, brown seaweeds, and sea tangles contain large amount of iodine. However they mistook the low iodine diet as a low salt diet and were not aware of foods and seasonings that are allowed on the low iodine diet. While self-efficacy related to consuming various fruits and vegetables, to choosing potatoes and sweet potatoes for snacks, and restricting consumption of eggs, milk and milk products, and processed foods was rated highly, self-efficacy for preparing foods without using sea salts was rated low. The self-efficacy score increased as their interest on the dietary life and perceived cooking skills were greater. Most perceived barriers toward practicing the low iodine diet were related to preparation of the low iodine menus. As their interest in the dietary life and cooking and perceived cooking skills were greater, the patients perceived barriers on practicing the low iodine diet less. While the patients showed higher self-efficacy and lower barrier perception on selecting foods low in iodine and restricting food high in iodine, they showed lower self-efficacy and higher barrier perceptions on preparing low iodine meals. Clinical dietitians should recognize the gap between what the patients should know and what they really know and identify strategies on how to improve self-efficacy and reduce perceived barriers on the low iodine diet. Recent literature and the findings of the study reveal that incorporating cooking classes into nutrition education for thyroid patients is effective to enhance self-efficacy and to reduce perceived barriers on the low iodine diet.