Do iodine supplements cause goiter and thyroid cancer?

In response to information that using iodine supplements increases thyroid disease due to excess of this micronutrient, the Ministry of Health has explained the disease conditions related to using iodine supplements.

No people with excess iodine have been recorded.

According to the results of the 2019-2020 Nutrition Survey, in all groups of subjects, urinary iodine levels were lower than recommended, according to the Ministry of Health.

The proportion of people with urinary iodine concentrations exceeding the threshold of 300 ppm was 0% (threshold above 300 ppm is the threshold for high urinary iodine).

The Ministry of Health said there have been no recorded cases of thyroid cancer or diseases caused by excess iodine.

With this result, the professional agency affirmed that the Vietnamese population still does not reach the recommended daily iodine intake. Up to now, there has been no medical literature mentioning the program of using iodized salt for the whole population (from 1994 to present) leading to consequences of thyroid disease.

In addition, according to reports from the Central Endocrinology Hospital and the Institute of Nutrition, Vietnam has not yet recorded any cases of patients with excess iodine.

According to the Ministry of Health, iodine deficiency or high iodine causing thyroid diseases is also classified as a consequence of iodine deficiency, this is the classification of the World Health Organization (WHO).

According to WHO, in areas with severe iodine deficiency, the incidence of hyperthyroidism in autoimmune thyroid nodules increases. After 5-10 years of regular iodine supplementation, the incidence of hyperthyroidism will decrease, corresponding to areas without iodine deficiency.

Hyperthyroidism is an autoimmune disease, medical treatment with synthetic antithyroid drugs is the main treatment. If medical treatment fails or immune factors remain high after a long period of medical treatment, surgery or radiation therapy should be chosen.

Thyroid cancer on the rise

According to the Ministry of Health's professional agency, the detection of thyroid cancer is increasing thanks to advances in diagnosis and people's awareness of disease screening.

Thyroid cancer is the most common malignancy of the endocrine system, and is on the rise globally. According to GLOBOCAN (global cancer database) 2020 data from the International Agency for Research on Cancer (IARC), thyroid cancer ranks 11th in the number of new cancer cases, accounting for 3% of all new cases of all cancers.

In Vietnam, according to GLOBOCAN data in 2020, similar to the situation in the world, thyroid cancer ranks 10th in the number of new cases, 6th in women in the rate of new cases among all types of cancer, 4 times higher than in men.

"The cause of this cancer is increasing due to the development of technology and people's awareness of early detection. There is no scientific document confirming that excess iodine causes thyroid cancer," the Ministry of Health explained.

In response to some opinions that iodine-fortified foods affect product quality and increase thyroid cancer, the Ministry of Health said that in the past 8 years, health agencies have not received scientific evidence related to the use of iodine-fortified salt causing changes in product color, taste or negative effects on consumers' health.

Results of the 2019 - 2020 general nutrition survey in Vietnam:

Only 27% of households use qualified iodized salt, while WHO's recommendation is over 90%.

The national urinary iodine test index in children (over 6 years old) is 113.3 mcg/l; in women of childbearing age it is 98.9 mcg/l (while the WHO recommended level for these subjects is 100 - 199 mcg/l); in pregnant women it is 85.3 mcg/l (the WHO recommended level for these subjects is 150 - 249 mcg/l).

Therefore, the iodine index in the tested groups and the index of households using iodized salt that meets disease prevention standards in Vietnam are all at the lower risk level and do not meet WHO recommendations.

WHO and other research agencies emphasize that large-scale micronutrient fortification is an effective public health intervention to prevent micronutrient deficiencies.

Fortification of foods with micronutrients to address globally prevalent micronutrient deficiencies does not result in toxicity or oversupplementation risks.

According to the 2021 report of the Global Network for the Prevention of Iodine Deficiency Disorders, Vietnam is still among the remaining 26 countries in the world lacking this micronutrient.

(Ministry of Health)

Source: https://thanhnien.vn/thuc-pham-bo-sung-i-ot-co-gay-buou-co-ung-thu-tuyen-giap-185241105112128206.htm