BiomarkersIodine (serum)
Minerals
Iodine (serum)
Iodine in your blood, needed for thyroid hormone
On your report it may say: Serum iodide
Iodine is needed to make thyroid hormone. Serum iodine is a specialised test and isn't interchangeable with urinary iodine; most people in India get enough iodine from iodised salt.
Typical ranges · µg/L
Recent iodine-containing contrast scans or supplements raise the result.
Ranges vary by lab, age and sex. The range printed on your report applies.
If it's low
Iodine intake may be low.
Common causes
- Not using iodised salt
- Very low dairy and seafood intake
What you might notice
- Goitre (swelling in the neck)
- Tiredness
If it's high
Usually recent iodine exposure from contrast dye, kelp or supplements.
Common causes
- Contrast scans
- Kelp or seaweed supplements
- Iodine supplements
What you might notice
- Thyroid changes in sensitive people
Testing
- Who should test
- Only when a doctor needs to assess iodine specifically.
- How to prepare
- Avoid iodine supplements and seafood before testing if asked.
- When to retest
- As your doctor advises.
What can help
Food sources
Talk to your doctor before taking iodine if you have a thyroid condition.
Common questions
Do I need iodine if I use iodised salt?
Usually not.
Serum or urine?
Urinary iodine is more commonly used to judge intake.
Explore further
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Build My Nutrition PlanFor general education only, not medical advice. Ranges shown are typical for adults; the range printed on your lab report applies. Talk to a qualified doctor about your results.