Iodine

Iodine is an essential trace element crucial for the production of thyroid hormones, which regulate growth, development, and metabolism. It also plays a vital role in maintaining healthy brain and nervous system function.

Iodine RDA (Recommended Dietary Allowance):

• Adults (19+ years): 150 µg/day
• Pregnant women: 220 µg/day
• Breastfeeding women: 290 µg/day
• Children (varies by age): 90-150 µg/day

ODA (Optimal Daily Allowance):

• 150-300 µg/day (depending on individual needs and health conditions)

Found in:

• Iodized salt
• Seafood (e.g., cod, tuna, shrimp)
• Seaweed (kelp, nori, wakame)
• Dairy products (milk, yogurt, cheese)
• Eggs
• Fortified foods (e.g., bread in some countries)
• Potatoes
• Cranberries

Helps with:

• Supporting the production of thyroid hormones (T3 and T4)
• Regulating metabolism and energy production
• Promoting healthy growth and development in children
• Maintaining cognitive function and brain health
• Supporting fetal brain development during pregnancy

Insufficient doses:

• Symptoms of deficiency:
  • Goiter (enlarged thyroid gland)
  • Hypothyroidism (fatigue, weight gain, sensitivity to cold)
  • Developmental delays in children
  • Cretinism (severe iodine deficiency during pregnancy)
  • Cognitive impairments and learning difficulties
• Deficiency is more common in regions where iodine intake from diet or fortified foods is low.

Excessive doses:

• Upper limit: 1,100 µg/day for adults
• Possible side effects of excessive intake:
  • Thyroid dysfunction (hyperthyroidism or hypothyroidism)
  • Thyroiditis (inflammation of the thyroid)
  • Nausea and abdominal pain
  • Metallic taste in the mouth (from acute overexposure)

Interactions:

• Synergy:
  • Works with selenium to support the conversion of T4 to the active hormone T3.
  • Combines with tyrosine (an amino acid) to produce thyroid hormones.
• Antagonistic interactions:
  • Excessive iodine can interfere with thyroid hormone synthesis, leading to thyroid dysfunction.
  • Goitrogens (found in raw cruciferous vegetables like broccoli and cabbage) may inhibit iodine absorption when consumed in large amounts.
  • Fluoride and bromine can compete with iodine for uptake in the thyroid gland.