pregnancy

Iodine in Pregnancy

The pregnancy

The right intake of iodine during pregnancy (or gestation) is essential for the correct and complete development of the fetus.

By itself, pregnancy is a female physiological state that takes over from the embryonic implantation in the uterine endometrium; the duration of this condition fluctuates around 38 weeks (with the necessary subjective differences), during which the needs and needs of the pregnant woman, and of the fruit of conception, are in continuous evolution.

Energy, plastic nutrients and essential molecules or microelements must comply with the basic and daily needs of the mother, as well as the development and growth of the fetus.

To learn more, read: diet during pregnancy »

requirement

Specifically, the intake of food iodine for an adult woman is around 150 micrograms (µg) / day and the increase of the recommended ration in case of gestation is equal to 25µg / day; ultimately, iodine intake in pregnancy should be around 175µg / day .

Foods rich in iodine

Ranking of food sources of iodine:

  • Fish and fishery products 50-100mcgr per 100g of edible portion
  • Human milk 30-70mcgr per 100g of edible portion
  • Fruit, vegetables, cereals and meat 2-5mcgr / 100g of edible portion

NB: In order to prevent the iodine deficiency that characterizes the entire peninsula, it is recommended to consume table salt (sodium chloride) supplemented with iodine for at least 2/3 of the total use. Unfortunately, to date the consumption of iodized salt does not yet reach levels sufficient to prevent iodine deficiency in the diet of Italians.

Functions

Iodine is a fundamental constituent of thyroid hormones, therefore its function correlates directly with the specific action of its hormones: T4 (tetraiodothyronine) and T3 (triiodothyronine). Large sample surveys on iodine food consumption and the relative appearance of deficiency symptoms have shown that, on average, the amount of iodine introduced with food does NOT reach the minimum requirement for proper organic functioning; it is in any case obligatory to specify that an iodine intake of 30-40mcgr / day seems sufficient to prevent the hormonal alterations of T4 and T3.

Effects of Deficiency

In 1990, the World Health Organization (WHO) estimated that over 20 million people worldwide suffer from a brain deficiency due to iodine deficiency in the diet; these data place the hypo-iodic diet in first place in the world ranking of preventable causes with respect to mental deficits.

The specific symptom of iodine deficiency is goiter, an anatomical alteration characterized by the increase in the pituitary hormone Thyroid Stimulating Hormone (TSH), in fact, this condition is justified by the over-stimulation of the thyroid gland and its increase in volume. This reaction is aimed at optimizing the uptake, fixation and extraction of the greatest possible amount of circulating blood iodine.

Excess of iodine

Very rare but still noteworthy is the super dosage; in this case toxic goiter (Plummer's disease) and hyperthyroidism may appear.

Importance in Pregnancy

Iodine in pregnancy is essential in order to prevent complications in fetal development; however, according to the Recommended Nutrient Intake Levels for the Italian population (LARN), the evaluation and dietary correction of iodine intake must necessarily be carried out in the pre-pregnancy period. Otherwise, similarly to the lack of the gestational period, the pre-pregnancy deficit may favor:

  • abortion
  • increase in peri-natal mortality
  • congenital anomalies
  • neurological alterations
  • mental deficit.

It seems that these complications, linked to iodine deficiency during pregnancy (especially in the first two quarters) and to its poor contribution in the pre-pregnancy period, can be easily prevented by guaranteeing only 1 mcg / kg of body weight / day; however, estimating the average gestational weight reached in Italy, a similar contribution would cover with difficulty even only 40-50% of the recommended daily ration.

Ultimately, in order to prevent complications on the fetus induced by the hypo-iodic malnutrition of the pregnant woman, it is advisable to check that the pre-pregnancy intake of iodine reaches 150mcgr / day and that the intake of iodine during pregnancy (especially in the first two quarters) is equal to 175mcgr / day.

Bibliography:

  • Medications in pregnancy - Emilio Arisi - pag 183-184.
  • Recommended intake levels of Nutrients for the Italian population (LARN) - Italian Society of Human Nutrition (SINU) - page 175: 179.