The thyroid is a gland located in the anterior part of the neck whose primary function is the regulation of the body’s metabolic processes through the secretion of thyroid hormone. For example, the thyroid gland modulates the metabolism of proteins, fats, and carbohydrates; it also exerts a significant influence on numerous physiological processes such as heat generation, cardiac output, and bone regeneration.
There are several pathologies that can affect thyroid gland function and alter the proportions of thyroid hormones that are available at any one time throughout the various tissues of the body. The five diseases that affect the thyroid gland are goiter, thyroid nodules, thyroid cancer, and most commonly Hypothyroidism, Hyperthyroidism.
The exact mechanisms that generate thyroid disease in the body are quite varied and may include autoimmune disorders, congenital defects, mineral deficiencies, pituitary disorders, surgical alterations, and side effects induced by medicinal or radiation therapies.
The most frequently observed symptoms of Hypothyroidism are:
1. Weight gain
Weight gain is one of the most characteristic symptoms of Hypothyroidism. Patients with this form of thyroid disease typically gain weight for no apparent reason, even after adjusting their diet and lifestyle. Hypothyroidism causes our body to have a lower energy expenditure and be significantly less efficient at burning calories, so patients tend to store fat more readily, which leads to weight gain.
2. Fatigue
All three thyroid hormones, i.e., TSH, T3, and T4, help the body regulate its energy metabolism. If not enough of these hormones reach the various tissues of the body, then a significant “slowing down” of various metabolic processes occurs. Consequently, patients end up experiencing near-constant fatigue or tiredness, and in some cases, extreme lethargy.
3. Cold Intolerance
Research has shown that there is a relationship between the effects of thyroid hormones and blood vessels. And how this, in turn, affects body temperature. This phenomenon directly affects the body’s ability to autoregulate its core temperature. Thus, patients with Hypothyroidism regularly become highly susceptible to cold temperatures.
4. Gastrointestinal Symptoms
A dramatic decrease in thyroid hormones can cause significant alterations to the digestive system, such as constipation, some types of gastritis, and even anemia. Increasing your physical activity, abstaining from smoking and alcoholic drinks, reducing stress, and abstaining from dietary irritants as well as drinking lots of fluids are the recommended therapeutic measures to counteract this side effect.
5. Depression
Some patients who are diagnosed and treated for depression actually have thyroid disease. It is important to note that depression is also associated with a series of somatic symptoms common to many pathologies, including Hypothyroidism. Therefore, it is currently recommended that patients with depressive symptoms undergo tests to measure thyroid hormone levels in order to rule out, or confirm, the existence of a disease of the thyroid gland.
6. Cramps
Hypothyroidism often causes sudden, temporary, unintentional, and painful contractions of the skeletal muscles of the body. Patients with Hypothyroidism are especially susceptible to suffering from leg cramps and pain, which can occur during bouts of physical exercise or even while at rest.
7. Rise in Blood Cholesterol Levels
Cholesterol is a lipid molecule that is present in all cells of the human body. The organism uses cholesterol to synthesize hormones and bile acids, and thus, it is integral to the digestion of fat. Cholesterol travels throughout the body by binding to specific proteins found in blood, and although dietary alterations can result in dramatic increases of circulating cholesterol, it can also happen as a result of some pathologies, such as Hypothyroidism. All thyroid hormones are heavily involved in hepatic processes that modulate the elimination of cholesterol from the body; therefore, when Hypothyroidism causes a drop in thyroid hormones levels, the liver becomes significantly less efficient at managing cholesterol in the blood.
8. Menstrual Irregularities
A woman’s reproductive cycle is intricately governed by hormonal changes. Hence, the functions of the thyroid gland greatly alter the female reproductive system, especially if the thyroid is hyperfunctioning. During puberty, thyroid diseases may cause either an early or late onset of menstruation. Furthermore, abnormally low thyroid hormone levels can cause heavier than normal menstrual flow, highly irregular periods, or even their absence entirely. Additionally, Hypothyroidism can also affect ovulation and increase the risk of developing ovarian cysts. In some extreme cases, severe Hypothyroidism can cause breast milk production in women who are not breastfeeding.
9. Cardiac Symptoms
Endocrine system disorders, such as hypofunction of the thyroid gland and its respective hormones, have multiple known effects on the cardiovascular system, and thus affect the structure of the heart and its functions. Particularly concerning is the fact that pericardial effusion is a frequent finding in patients with Hypothyroidism. However, the most common cardiac manifestation among hypothyroid patients is bradycardia or abnormal reduction in heart rate. Bradycardia, which results in heart rates below 60 beats per minute is not, in and of itself, a dangerous condition. However, it has the potential to cause significant harm if the heart stops pumping sufficient oxygen-rich blood to the brain and other organs and tissues of the body.
The most frequently observed symptoms of Hyperthyroidism are:
10. Tachycardia
Hyperthyroidism, in contrast to Hypothyroidism, represents marked hyperactivity of the thyroid gland and the subsequent overproduction of thyroid hormones. As such, whereas Hypothyroidism is characterized by a “slowing down” of the body’s metabolic processes, Hyperthyroidism results in a dramatic “speeding up” of the metabolism. One of the primary consequences of this effect is the appearance of tachycardia or a sudden rise in the heart’s cardiac frequency. In other words, patients with tachycardia report experiencing too-fast contraction of the heart’s ventricles and by having a resting heart rate that exceeds 100 beats per minute.
11. Weight Loss
Hyperthyroidism is a metabolic disorder in which the endocrine thyroid gland produces significantly more thyroid hormones, i.e., TSH, T3, and T4 than the body needs. This influx of hormones results in a dramatic increase in the body’s basal metabolic rate and thus increases the body’s energy requirements. Consequently, patients use the energy they receive from food much faster than normal, and so they frequently lose large amounts of weight despite not doing any extra physical activity.
12. Goiter
The term goiter describes a condition wherein there is an increase in the size of the thyroid gland. According to its characteristics, goiter can be diffuse, that is, at the expense of a global and regular increase of the gland; or nodular, in which there are focal increases in thyroid size. Although a high percentage of goiters are present without any apparent alteration in thyroid hormones, many times, they are due to the formation of cystic, hemorrhagic or solid nodules as a result of the focal proliferation of thyroid tissue. When there are enzymatic deficiencies in the synthesis of thyroid hormones, an increase in TSH can lead to an increase in glandular size. Therefore, many cases of Hyperthyroidism present with goiter because in order to produce an increased level of thyroid hormones, it is necessary that the gland be larger and have a greater synthetic capacity.
13. Hyperhidrosis
Perspiration, or sweating, is a physiological process that is necessary to control body temperature during physical exertion or in harsh environments. Sweating is regulated by the sympathetic nervous system. When this system suffers from pathological alterations, it can become hyperactive and operate at a higher level causing profuse sweating in certain areas of the body at times which do not correspond with increased body temperature. This condition is known as hyperhidrosis. Hyperhidrosis can be primary, that is, of unknown cause or secondary to endocrine disorders such as thyroid diseases.
14. Behavioral Symptoms
Variations in hormone levels, even a small increase in thyroid hormones, directly affect cognitive and emotional responses in affected patients, including preferences, sexual behavior, appetite, and attitudes. Among the most common complaints in patients with hyperthyroidism are irritability, increased nervousness, difficulty concentrating, impatience, and sudden mood swings.
15. Sleep Disorders
In the presence of Hyperthyroidism, the body’s basal metabolism accelerates, so it is common for affected patients to feel abnormally energetic. These symptoms of Hyperthyroidism are caused by excessive levels of circulating thyroid hormone, which acts as a powerful stimulant. In these cases, the patients frequently experience restlessness, anxiety, heart palpitations, restless leg syndrome, and in more than a few cases, insomnia. Other patients with Hyperthyroidism complain of fatigue and exhaustion, while at the same time feeling anxious. All of these symptoms act as sleep disturbances with patients reporting difficulty falling asleep and waking up with the sensation of not having rested.
Conclusion
Treatment for thyroid disease depends on the severity of the symptoms, as well as the patient’s age and the existence of other conditions. In general, treatment with levothyroxine is recommended, which is taken orally as a pill. Levothyroxine works by bringing the patient’s levels of thyroid hormones closer to a healthy baseline, so the exact dosage required may vary between each patient.
Most patients require follow up check-ups every two or three months during the beginning of the treatment to check their hormone levels and adjust dosages accordingly. Thankfully, with proper treatment, the majority of patients who are diagnosed with thyroid disease manage to overcome it and lead normal lives.