What is the recommended dose of iodine supplementation for adults and pregnant women with critical iodine needs?

From the Guidelines

The recommended daily iodine supplementation for adults is 150 micrograms, while pregnant women should consume 250 micrograms daily, as recommended by the WHO/UNICEF/International Council for the Control of IDD 1. This higher requirement during pregnancy is essential because iodine is critical for fetal brain development and thyroid function. Iodine supplements are typically available as potassium iodide tablets or as part of prenatal vitamins. For those with diagnosed deficiency, healthcare providers might recommend higher doses temporarily. Most people can obtain adequate iodine through iodized salt, seafood, dairy products, and enriched bread. However, those following vegan diets, avoiding iodized salt, or living in regions with iodine-poor soil may need supplements. Excessive iodine intake can cause thyroid dysfunction, so it's essential not to exceed 1,100 micrograms daily for adults, as suggested by the Institute of Medicine 1. Before starting supplementation, consulting with a healthcare provider is advisable, especially for those with existing thyroid conditions. Some studies have suggested that supplementation with iodine for a long period prior to conception may be beneficial for women living in mild-to-moderate deficient areas 1. Key points to consider include:

• Iodine requirements vary with age, with no sex differentiations in the recommendation, besides from pregnancy and lactation 1.
• The European Food Safety Authority proposed a new reference value of adequate intake for pregnant women of 200 µg/d 1.
• A large-scale cross-sectional study in Chinese pregnant women suggested that UIC in pregnant women should not exceed 250 µg/l in iodine-sufficient regions, due to high risk of subclinical hypothyroidism 1. It is crucial to weigh the benefits and potential harms of iodine supplementation, as some studies have indicated both positive and negative health effects 1. Ultimately, the decision to supplement with iodine should be made in consultation with a healthcare provider, taking into account individual needs and circumstances.

From the FDA Drug Label

DIRECTIONS FOR USE: Use only as directed by public officials if a nuclear radiation emergency happens. Dose: Adults over 18 years 2 mL every day (130 mg) Children over 12 years to 18 years 2 mL every day (130 mg) who weigh at least 150 pounds Children over 12 years to 18 years 1 mL every day (65 mg) who weigh less than 150 pounds Children over 3 years to 12 years 1 mL every day (65 mg) Children over 1 month to 3 years 0.5 mL every day (32.5 mg) Babies at birth to 1 month 0.25 mL every day (16.25 mg)

The recommended dose of iodine supplementation for adults is 130 mg per day, and for pregnant women, the dose is not explicitly stated, but it can be inferred that it would be the same as for adults, which is 130 mg per day, as there is no distinction made for pregnant women in the provided text 2.

• Key points:
  • The dose for adults and pregnant women is 130 mg per day.
  • The dosage is to be taken every 24 hours as directed by public officials.
  • It is crucial not to exceed the recommended dose to minimize the risk of side effects.

From the Research

Iodine Supplementation for Adults and Pregnant Women

• The recommended dose of iodine supplementation for adults and pregnant women with critical iodine needs is not explicitly stated in the provided studies.
• However, study 3 suggests that small amounts of supplementary iodine (250 microg) can cause slight but significant changes in thyroid hormone function in predisposed individuals.
• Study 4 mentions that the starting dose of potassium iodide is around 50 mg/day for mild cases of Graves' disease, but this is not directly related to iodine supplementation for critical iodine needs.
• Study 5 discusses the potential risks of excess iodine intake, but does not provide guidance on recommended supplementation doses.
• Studies 6 and 7 focus on the use of potassium iodide in the treatment of thyrotoxicosis and thyroid storm, respectively, and do not address iodine supplementation for critical iodine needs.

Key Findings

• Iodine supplementation can affect thyroid hormone function, particularly in individuals with preexisting thyroid disease or those previously exposed to iodine deficiency 3, 5.
• The use of potassium iodide in combination with antithyroid drugs may improve short-term control of Graves' hyperthyroidism 6.
• Early potassium iodide use may be associated with reduced in-hospital mortality in patients with thyroid storm and Graves' disease 7.

Iodine Intake and Thyroid Function

• Excess iodine intake can precipitate hyperthyroidism, hypothyroidism, goiter, and/or thyroid autoimmunity, particularly in individuals with preexisting thyroid disease or those previously exposed to iodine deficiency 5.
• The median urinary iodine concentration (UIC) can accurately identify populations with excessive iodine intakes 5.