The thyroid, a butterfly-shaped gland weighing approximately 20 grams, is discreetly located at the front of the neck. It has a great influence on human health because its hormones, T3 and T4, regulate vital functions such as metabolism, body temperature, heart rate, fertility, and brain and intestinal function, covering memory, attention, reasoning, and emotional balance.
When the gland deregulates hormone production, whether producing in excess or in deficiency, signs can appear in unexpected places and are often not associated with the thyroid as the main cause. In the case of hypothyroidism, the gland operates slowly, generating progressive symptoms such as continuous fatigue, difficulty focusing and reasoning, forgetfulness, excessive drowsiness, and depression. Other signs include dry skin, hair loss, brittle nails, constipation, and a constant feeling of cold.
Helton Ramos, a thyroidologist and professor at the Federal University of Bahia (UFBA), points out that due to the non-specific nature of these symptoms, patients tend to ignore them, which can delay diagnosis. However, hypothyroidism does not always present obvious signs; subclinical hypothyroidism can only be detected by hormonal changes in tests, while the individual feels well. Ramos emphasizes that this condition can be linked to increased cholesterol, higher cardiovascular risk, worsening heart function, and a greater chance of progressing to overt hypothyroidism, underlining the need for medical monitoring even without symptoms.
Regarding weight gain, specialists report that it is usually modest, in the range of 2 to 5 kg, and is not the primary cause of obesity. In hyperthyroidism, however, overproduction of hormones accelerates bodily processes. Although many people associate the problem with weight loss, specialists warn that this is just a possible symptom. More common symptoms include irritability, insomnia, slight tremors in the hands, sporadic palpitations, and constant agitation.
Danielle Macellaro, an endocrinologist at Einstein Israelite Hospital, describes that in the elderly, the hyperthyroid state can be more subtle, manifesting as fatigue, muscle weakness, or cardiac changes. In certain cases, the eyes serve as a warning sign. Graves' disease, the main autoimmune cause of hyperthyroidism, can cause redness, excessive tearing, eyelid swelling, light sensitivity, and, in severe cases, exophthalmos. Ramos emphasizes that early recognition of these eye signs is crucial, as thyroid eye disease can seriously affect quality of life and, rarely, threaten vision if not treated correctly.
Although thyroid disorders are more prevalent in women, affecting menstrual cycles, sexual desire, and pregnancy, men also suffer consequences. Both hypothyroidism and hyperthyroidism can decrease libido, impair sperm quality, make erection difficult, and compromise fertility. A 2024 scientific review in the Journal of Diabetes & Metabolic Disorders confirmed the link between thyroid diseases and a higher incidence of male sexual dysfunction, although these issues improve with appropriate treatment, according to the Einstein physician.
What about nodules?
Thyroid nodules or hormonal changes often do not cause visible symptoms. When the gland volume increases, goiter occurs, which can generate a protrusion at the front of the neck, noticeable during swallowing. Hardened, rapidly growing nodules should attract attention if accompanied by persistent hoarseness, difficulty swallowing, or swollen cervical lymph nodes.
Most of these changes are not related to cancer, according to Macellaro, since between 90% and 95% of thyroid nodules are benign. Furthermore, she states that even when cancer is diagnosed, the most common thyroid tumors have high cure rates with appropriate treatment. Despite this, the incidence of thyroid cancer has been increasing drastically in several countries. In Brazil, the National Cancer Institute (INCA) estimates about 16,000 new annual cases, making it one of the most common cancers in women. This increase is attributed both to greater access to imaging exams and the detection of small tumors, but recent studies point to environmental, metabolic factors, and lifestyle changes as contributors.
Tea and supplements do not treat the thyroid
Not all thyroid diseases can be prevented, especially those of genetic or autoimmune origin. However, it is possible to promote gland health through a balanced diet, avoiding supplementation without medical guidance, and maintaining follow-up if there is a family history. It is important to note that there is no proof that teas, supplements, or formulas sold online cure thyroid diseases. Nutrients such as selenium and iodine are crucial, but excess can be as harmful as deficiency; for example, one or two Brazil nuts per day provide sufficient selenium.
Early identification of any change in the area remains essential. Self-examination does not replace a doctor's consultation but can help observe visible changes. To perform it, the individual should stand in front of a mirror, slightly tilt the chin up, and observe the area under the Adam's apple and above the collarbones. After taking a sip of water and swallowing, they should gently palpate the area, checking for bulges, asymmetries, or unusual movements. Any persistent change requires evaluation by an endocrinologist.
Diagnosing thyroid dysfunctions involves blood tests to measure free TSH, T3, and T4 levels, as well as thyroid antibodies to screen for autoimmune diseases such as Hashimoto's Thyroiditis or Graves' Disease. Ultrasound investigates the size and presence of nodules. Treatment for hypothyroidism and hyperthyroidism is mainly pharmacological, aiming to normalize hormone levels. However, patients with hyperthyroidism may require radioactive iodine therapy or surgery. Danielle Macellaro concludes that the earlier the change is identified, the greater the chances of preventing complications and maintaining the patient's quality of life.
