Vitamin A supplementation in iodine-deficient African children decreases thyrotropin stimulation of the thyroid and reduces the goiter rate

Abstract

Iodine prophylaxis is effective in controlling ID in areas of poor vitamin A status. VA supplements are effective in treating VAD in areas of mild ID and have an additional benefit-through suppression of the pituitary TSHbeta gene, VAS can decrease excess TSH stimulation of the thyroid and thereby reduce the risk of goiter and its sequelae.

Thyroid volume, selenium levels and nutritional habits in a rural region in Albania

“…There are reports which correlate the manifestation of goiter with elements of diet other than iodine, such as low levels of selenium, the consumption of foods rich in thiocyanate, the insufficiency of vitamin A, iron deficiency and low intake of proteins. 7,9,[16][17][18] The countries in which studies were conducted in order to assess the effect of dietary factors in patients with sufficient intake of iodine and which found a correlation with the above-mentioned parameters are mainly developing countries that have serious problems with malnutrition. It is possible that in our study the lower meat intake may have contributed to mild deficiencies in various micronutrients; however, in this population we did not measure iron or vitamin A concentrations.…”

“…This is more obvious in areas with a low standard of living where the replenishment of such micronutrients is of importance in the treatment of goiter. 7,8,[21][22][23][24] On the other hand, thiocyanates contained in vegetables such as cabbage, broccoli and soya are well known goitrogens; thiocyanates also exist as environmental toxins and in cigarette smoke. 10,25 Studies with a larger number of cases are needed in order to clarify with a greater statistical significance any correlation of this or other dietary micro-and macronutrients with the development of goiter.…”

“…Such nutritional factors include iodine, selenium, vitamin A and iron as well as foods containing thiocyanates and proteins. [6][7][8][9][10] The purpose of this paper was to study thyroid status in inhabitants of the region of Gyrocaster in Southwestern Albania, who were attending the outpatients' clinic for routine examination, in relation to their dietary habits and their socioeconomic level.…”

ENDOCRINE SIDE-EFFECTS OF ANTI-CANCER DRUGS: The impact of retinoids on the thyroid axis

“…In 1997, Coya et al (27) found that rats, either euthyroid or hypothyroid, treated with retinoic acid, showed a decrease in spontaneous basal TSH levels and TSH responses to TRH. In a quite different setting, data with similar meaning were recently reported in mildly iodine-deficient children in whom vitamin A (retinyl palmitate) supplementation decreased excess TSH stimulation thereby reducing the risk of goiter (28).…”

Progress towards eliminating iodine deficiency in South Africa

“…39 The survey nevertheless showed that aggregated national and provincial urinary iodine data may mask pockets of persisting iodine deficiency, as was later confirmed in rural schools in the Limpopo province. 40 In the 199 national survey a median urinary iodine intake of 242 µg/L was found in children of the Northern Cape province. This value, indicating more than adequate iodine intake in this province, most likely resulted from a combination of the salt iodisation programme and abundant iodine in the environment as reflected by high iodine concentrations in the drinking water of some Northern Cape towns.…”