Iodine is a mineral that is essential for proper thyroid functioning. The triiodothyronine (T3) and thyroxine (T4) thyroid hormones are tyrosine-based hormones produced by the precious thyroid gland and are necessary for a proper and efficient metabolism. The thyroid controls fundamental metabolic functions: regulation of body temperature, growth and development of tissues and energy levels. All these actions are activated through the synthesis of Tiroxina (T4) and Triiodothyronine (T3), whose iodine content is about 60%. Iodine is a key component in the production of T3 and T4. Insufficient iodine causes a reduced production of T3 and T4, which can create enlargement of the thyroid gland. A deficiency of iodine can also result in weight gain, low energy, a tendency to depression and is associated with cardiovascular disease; it also promotes cognitive decline. When iodine deficiency is severe, it causes goitre and cretinism, mental retardation, infertility and an increase in perinatal death. Unfortunately, Iodine deficiency is one of the main health emergencies, not only in Italy but also worldwide, so much so that it produces an alert by health organizations such as WHO which, in 2010, included iodine in the list of ten most important micronutrients as regards need. It should also be noted that in 2005 the Italian Health Ministry issued a law for the diffusion of iodised salt for cooking in order to reduce the incidence of iodine deficiency (about 10% of the population are affected). In pregnancy and breast-feeding, as well as in young children, the integration of iodine is essential for the proper functioning and formation of the brain: a deficiency can lead to varying degrees of cognitive deficit. To support maximum efficiency in thyroid activity, the presence of Selenium is necessary. Selenium is an essential element of the enzymatic system that has the task of transforming thyroxine (t4) into triiodothyronine (T3) at the tissue level, activating the deiodinase enzyme. Selenium is a very important mineral for keeping the body healthy. Its powerful antioxidant effectis well known; it plays a protective role for cells against the aggression of free radicals, thus counteracting the effects of oxidative stress, and acts in preventing cellular aging. Among others, in this way selenium preserves the tissues from degeneration and keeps the skin elastic and young. In addition, this important mineral stimulates the immune system, as well as having an anti-inflammatory function and, together with vitamin C, protects the body from infections, especially seasonal illnesses and flu viruses. It protects against the risk of cardiovascular dysfunctions and other diseases related to aging, such as arthritis, arteriosclerosis, etc. Selenium is useful for the prevention of some forms of tumours, in particular prostate cancer (this is because selenoproteins are directly involved in the production of testosterone). For all these reasons, it has been defined as a mineral with anti-aging effects. But as already mentioned, Selenium is fundamental for the proper functioning of the thyroid, regulating its activity and carrying out a protective function for this gland, as well as being directly involved in the transformation of the T4 hormone into T3. In fact, there may instead be a deficiency of this mineral if you suffer from metabolic dysfunctions related to thyroid activity, such as hypothyroidism. To ensure the right intake of iodine and selenium, it is important to follow a rich and balanced diet that includes all the foods containing these two precious microelements, and it is recommended replacing the sea salt used in the kitchen with iodised salt. In most cases, these indications are able to prevent a lack of iodine, but sometimes diet alone is not enough to correct these imbalances and for some people, a targeted integration of these two elements is nevertheless necessary for returning to physiological ranges and supporting physiological thyroid activity thanks to products like Tiriosel. Those who have a lazy and fatigued thyroid are found to have low T3 and T4 hormone levels, or a Tsh value that is too low. Often, before intervening with diagnostic action and particular in-depth examinations, specialists recommend a food supplement based on iodine and selenium, intended to rebalance any deficiencies or increased needs in order to encourage physiological conversion into active efficient hormones.