Question
The most sensitive indicator of environmental iodine deficiency is:
| A. | Prevalence of goiter |
| B. |
Prevalence of neonatal hypothyroidism |
| C. |
Prevalence of cretinism |
| D. |
Urinary iodine excretion |
Show Answer
|
Correct Answer » D Explanation |
 |
Environmental iodine deficiency is best assessed at the population level. The ideal indicator should reflect recent iodine intake and detect deficiency before clinical manifestations such as goiter or cretinism develop.
Since more than 90% of ingested iodine is excreted in urine, urinary iodine concentration (UIC) is the most sensitive indicator of current iodine status in a community and is recommended by the World Health Organization (WHO) for population surveillance.
Explanation of Each Option
A. Prevalence of goiter — Incorrect
- Goiter is a consequence of chronic iodine deficiency.
- It reflects long-term deficiency rather than current iodine intake.
- It is less sensitive than urinary iodine estimation.
B. Prevalence of neonatal hypothyroidism — Incorrect
- Neonatal thyroid-stimulating hormone (TSH) screening can indicate iodine deficiency in a population.
- However, it is less sensitive and less commonly used than urinary iodine estimation for environmental assessment.
C. Prevalence of cretinism — Incorrect
- Cretinism is a severe, late manifestation of prolonged iodine deficiency.
- It is neither sensitive nor useful for early detection of environmental iodine deficiency.
D. Urinary iodine excretion — Correct
- Reflects recent iodine intake.
- More than 90% of dietary iodine is excreted in urine.
- Recommended by the WHO as the preferred indicator for assessing iodine nutrition in populations.
