Hypothyroidism and Selenium

Safety Issues

The US Institute of Medicine issues guidelines for the maximum total daily intake of various nutrients, based on estimations of what should be safe for virtually all healthy individuals. These tolerable upper intake levels (ULs) are, thus, conservative guidelines. For selenium, they have been set as follows: ¹

• Infants

• 0-6 months: 45 mcg

• 7-12 months: 60 mcg

• Children

• 1-3 years: 90 mcg

• 4-8 years: 150 mcg

• 9-13 years: 280 mcg

• Males and Females

• 14 years and older: 400 mcg

• Pregnant or Nursing Women: 400 mcg

Note that these dosages apply to combined dietary and supplemental intake of selenium. When deciding how much selenium it’s safe to take, keep in mind that most adults already receive about 100 mcg of selenium in the daily diet.

Maximum safe doses of selenium for individuals with severe liver or kidney disease have not been established. There is some evidence that supplementing selenium over the long-term in areas where selenium is already adequate in the diet may increase the risk of diabetes and perhaps hypercholesterolemia. ² Highly excessive selenium intake, beginning at about 900 mcg daily, can cause selenium toxicity. ³ Signs include depression, nervousness, emotional instability, nausea, vomiting, and in some cases loss of hair and fingernails.

Interactions You Should Know About

If you are taking medications that reduce stomach acid, such as H 2 blockers or proton pump inhibitors , you may need extra selenium.