Ideas in this flowchart

• Selenium and iodine: sources, intake, functions, deficiency, and toxicity
• Selenium
• Iodine
• Sources include meat, seafood, eggs, and nuts.
• The recommended adult intake is 55 mcg/day.
• Selenium is essential for thyroid hormone activity.
• Deficiency can cause fatigue, muscle pain, weakness, and Keshan disease.
• Low-selenium soil places populations at risk for deficiency.
• Toxicity can cause nausea, diarrhea, vomiting, and fatigue.
• The tolerable upper intake level is 400 mcg/day.
• Sources include iodized salt, seaweed, and dairy products.
• The recommended intake is 150 mcg/day.
• Iodine is involved in thyroid hormone production, metabolism, growth, and development.
• Deficiency can cause goiter, cretinism, fatigue, depression, weight gain, itchy skin, and a low heart rate.
• Low-iodine soil and lack of iodized salt place populations at risk for deficiency.
• Toxicity can cause an enlarged thyroid.
• The tolerable upper intake level is 1110 mcg/day.