Currently, it is not known how to prevent most cases of hypothyroidism that occur in industrialized countries. All the same, a early diagnosis and food which provides all the nutrients essential for the proper functioning of the thyroid gland help prevent exacerbation of symptoms and worsening of the disease.

Elsewhere in the world, prevention is possible in cases where nutritional deficiencies (especially iodine, selenium or zinc), or an excess of iodine, are the cause of hypothyroidism.

A screening test forhypothyroidism congenital is performed in hospital in all newborns, in industrialized countries. Blood samples are taken from the heel on a filter paper, ideally 3 to 6 days after birth. The TSH hormone level is first measured, then the T4 hormone level in borderline cases. Studies indicate that this early detection helps treat the disease quickly and prevent its consequences, such as mental retardation and growth retardation⁵.

In adults, the benefits of screening have not been demonstrated. Therefore, the Canadian and US Preventive Medicine Study Groups do not recommend universal screening. However, several medical associations recommend that the TSH hormone level in the blood be measured periodically in people at risk (taking a drug at risk or having a family history of hypothyroidism) and in those who have symptoms of hypothyroidism.

Food

To produce thyroid hormones, the thyroid needs a sufficient amount of trace elements, especiallyiodine, selenium and zinc. A deficiency in any of these elements can slow down the functioning of the thyroid. Iodine deficiency is rather rare in industrialized countries due to the use of iodized table salt. A healthy and varied diet provides all these trace elements. In 2007, according to the World Health Organization, iodine deficiency, although less frequent than before, remained a public health problem in 47 countries⁶. If in doubt, do laboratory tests to detect the nutrient deficiency (s) and fill them to restore function.

Here are some good food sources:

— d’iodine : sea fish (anchovies, sea bream, mackerel, cod, sardines, etc.), seaweed and table salt.

– of selenium : Brazil nuts, oysters and tuna.

– of zinc : seafood (oysters at the top of the list), beef and veal, beef or pork liver.

For other sources of selenium or zinc, see our corresponding sheets.

Daily iodine requirement. In adults, a daily intake of 150 µg per day is recommended. Requirements rise to 200 µg per day in pregnant or breastfeeding women. In order not to exceed the recommended daily allowance, the World Health Organization recommends consuming a maximum of 5 g of iodized table salt per day, which corresponds to approximately 1 tsp. salt per day¹³. This amount of salt provides 50 µg to 75 µg of iodine per day.

In people with a problem with the functioning of the thyroid, it is possible that excess iodine worsens the disease and interferes with treatment. It is difficult to quantify what constitutes excessive iodine consumption. This depends on the amount of iodine usually consumed and varies greatly from region to region of the world. According to the World Health Organization, an intake of no more than 1 µg (the equivalent of 000 mg) of iodine per day is considered safe.¹³.

Many natural products intended for the treatment of thyroid diseases are rich in iodine (iodine tincture, seaweed-based iodine supplements, etc.). As a precaution, their use should be restricted to people with iodine deficiency (which is rare). Consult a physician or health care professional knowledgeable in nutrition before consuming such a product.

Take the prescribed treatment daily and consult your doctor regularly to ensure that the dosage of treatment remains correct.