Thyroid Diseases

Thyroid diseases are those pathologies that affect the functioning of the thyroid gland. The main function of this gland, located at the base of the neck just below the Adam's apple, is to secrete thyroid hormones, which regulate metabolism, that is, how the body uses energy. To do this, they stimulate body tissues to produce proteins and increase the amount of oxygen used by cells. Therefore, its functioning affects most vital functions, such as growth, breathing, heart rate, digestion, and maintaining body temperature, among others.

The most common thyroid diseases are as follows:

• Hyperthyroidism: excessive production of hormones.
• Hypothyroidism: insufficient production of thyroid hormones.
• Goiter: abnormal enlargement of the thyroid that usually causes improper functioning of the gland.
• Thyroid Nodules: clusters of thyroid cells that form tumors, generally benign and asymptomatic.
• Thyroiditis: inflammation of the gland. It can be acute or chronic.
• Thyroid Cancer: uncontrolled growth of thyroid cells. It is rare.

Symptoms

Each thyroid disease has its own symptoms:

Symptoms of hyperthyroidism:

• Weight loss (even when eating more).
• Increased appetite.
• Rapid heart rate.
• Nervousness, anxiety, and irritability.
• Difficulty sleeping.
• Tremors in the hands.
• Increased sweating.
• Higher intolerance to heat.
• Muscle weakness.
• Increased bowel movements.
• In women, reduced frequency and intensity of menstrual periods.
• Swollen, red, or irritated eyes. Light sensitivity or double vision may occur.

Symptoms of hypothyroidism:

• Weight gain (without increased food intake).
• Sadness or depression.
• Memory problems.
• Slow heart rate.
• Muscle weakness.
• Fatigue.
• Higher intolerance to cold.
• Joint or muscle pain.
• Pale and dry skin.
• Constipation.
• Reduced sweating.
• Fine, dry hair.
• Facial swelling.
• Goiter.
• Hoarseness in the voice.
• In women, more intense menstrual bleeding.

Symptoms of goiter:

• Swelling in the neck: a lump that can be felt or seen.
• If the lump is too large, neck stiffness, coughing, or difficulty breathing or swallowing may appear.

Symptoms of thyroid nodules:

• Usually, they don’t present symptoms, although occasionally they can be visible.
• If the nodules press against other neck structures, goiter, pain, hoarseness, or difficulty breathing or swallowing may occur.
• If the nodules produce thyroid hormones, symptoms of hyperthyroidism will manifest.

Symptoms of thyroiditis:

• Symptoms of hypothyroidism if thyroiditis causes slow deterioration and destruction of thyroid cells.
• Symptoms of hyperthyroidism if it causes rapid deterioration leading to the release of more hormones.
• A sore throat may occur.

Symptoms of thyroid cancer:

• Can be confused with symptoms of nodules or goiter.
• Swelling or lump in the neck.
• Hoarseness in the voice.
• Difficulty swallowing.

Causes

The causes of thyroid diseases vary depending on each specific pathology:

Causes of hyperthyroidism:

• Graves-Basedow disease: the most common cause. It is a chronic autoimmune condition in which the body produces autoantibodies against the thyroid that stimulate excessive hormone production.
• Presence of toxic nodules that secrete hormones.
• Thyroiditis, in its initial phase.
• Some medications, such as interferon or amiodarone.
• Excess iodine: iodine is essential for thyroid hormone production.

Causes of hypothyroidism:

• Hashimoto’s disease: a chronic autoimmune disorder that produces autoantibodies that inflame and damage the thyroid.
• Thyroiditis.
• Iodine deficiency.
• Radiation treatments or treatments for hyperthyroidism.
• Congenital thyroid or pituitary disorders.
• Total or partial removal of the gland during surgery.

Causes of goiter:

• Iodine deficiency.
• Other thyroid disorders, such as Graves' disease, Hashimoto’s disease, thyroiditis, thyroid nodules, or thyroid cancer.
• Pregnancy: during gestation, human chorionic gonadotropin (hCG) is produced, which can cause thyroid hyperactivity and enlargement.

Causes of thyroid nodules:

• The exact mechanism for the appearance and growth of nodules is unknown, but it may be related to iodine deficiency or have a hereditary component.

Causes of thyroiditis:

• Autoimmune disorder (Hashimoto’s disease).
• Postpartum: an immune alteration similar to Hashimoto’s disease can occur.
• Viral or bacterial infection.
• Radiation treatments.
• Trauma or surgery in the area.
• Some medications, such as interferon or lithium.

Causes of thyroid cancer:

• Thyroid cells develop mutations in DNA that accelerate their growth. These accumulate and form tumors that invade nearby tissues and may spread. The cause of these mutations is not clear.

Risk Factors

The risk of thyroid disorders increases with the following factors:

• Gender: thyroid disorders are more common in women.
• Age: the risk increases after age 60.
• Pregnancy, postpartum, and menopause.
• Family history.
• Presence of autoimmune diseases.
• Iodine deficiency or excess.
• Use of medications that affect the thyroid.
• Radiation treatments.

Complications

If thyroid gland pathologies are not properly treated, they can lead to:

• Weight problems, such as obesity or excessive weight loss.
• Excessive thyroid hormones can cause heart problems, such as arrhythmias, strokes, or heart failure.
• Osteoporosis due to insufficient calcium supply to the bones.
• Hypercholesterolemia due to insufficient thyroid hormone production.
• Damage to peripheral nerves, leading to pain and numbness in the extremities.
• Ovulation disturbances and limited fertility.
• In some cases, myxedema coma, a medical emergency that poses a life-threatening risk.
• In rare cases, hyperthyroidism can cause a thyroid crisis, or thyrotoxic storm, which can be fatal.

Prevention

To improve thyroid function, the following tips can be followed:

• Follow a balanced diet, rich in vegetables and lean proteins.
• Avoid processed and refined foods.
• Cook cruciferous vegetables, such as broccoli, cabbage, or cauliflower: they contain goitrogens, natural chemicals that interfere with thyroid hormone synthesis. Cooking deactivates these substances.
• Exercise regularly, as it helps regulate metabolism.
• Manage stress: stress slows down metabolism.
• Reduce alcohol, tobacco, and caffeine consumption because they accelerate metabolism.

What doctor treats thyroid diseases?

Thyroid diseases are diagnosed and treated in the endocrinology unit, and the follow-up of some of these processes can also be carried out by family medicine specialists.

In many cases, they are detected in the check-up unit or during gynecological exams.