89airtight container along with plastic-pack and kept away from the furnace. Once
the pack is opened, it has to be consumed within 4 weeks. Salt should prefera-
bly be added on table rather than during cooking, as iodine quickly sublimates
on exposure to heat.- What is the recommended daily allowance for iodine?
Recommended daily allowance (RDA) for iodine as suggested by WHO is
summarized in the table given below.Age RDA of iodine (μg/day)
0–5 years 90
6–12 years 120
>12 years 150
Pregnancy and lactation 250- What are the causes of hypothyroidism in children?
Iodine defi ciency is the most common cause of primary hypothyroidism in chil-
dren worldwide. However, in iodine-suffi cient regions, the commonest cause is
Hashimoto’s thyroiditis. Other causes of hypothyroidism in children include
neck irradiation, delayed-onset dyshormonogenesis, ectopic thyroid gland,
consumptive hypothyroidism, and secondary hypothyroidism (pituitary tran-
scription factor defects and sellar–suprasellar mass). The fi gure illustrated
below shows primary hypothyroidism in a child with ectopic thyroid gland
(Figs. 3.10 and 3.11 ).Fig. 3.10 Lingual thyroid
in a child with juvenile
hypothyroidism
3 Thyroid Disorders in Children