One in three people in Germany suffers from a pathological change in the thyroid gland.
The most common thyroid disorder is hypothyroidism, a condition in which the thyroid gland produces less hormones than the body needs (hypothyroidism) 
This condition occurs, for example, as a result of thyroid inflammation. („Hashimoto-Thyreoiditis).
symptoms
Hypothyroidism is characterized by a gradual but persistent progression. 

• Increased sensitivity to cold
• Slowed reflexes
• Memory loss, depressive moods
• Weight gain and elevated cholesterol levels
• Muscle weakness and muscle stiffness
• Brittle, fragile hair, increased hair loss, brittle nails
• Pale, cool, and dry skin
• Hoarse, deep voice; slow, slurred speech
• Chronic constipation
• Decreased sexual desire and potency in men
• Slowed heartbeat, lowered blood pressure, rarely elevated blood pressure

Thyroid nodule
Tissue growths can also occur in the thyroid gland, which are usually first detected by ultrasound as incidental findings, known as nodules. 99.9% of thyroid nodules are benign.. 
In Germany, about one-third of the population has such nodular changes. However, very few of those affected have symptoms. 
According to current knowledge, the causes of nodule formation in the thyroid gland are primarily attributable to genetic, i.e., familial predisposition. 

However, thyroid nodules can cause discomfort when they reach a certain size, leading to a lump in the throat, tightness, and difficulty swallowing. 
Is it a hormone-active (“hot”) nodules, this can lead to symptoms of hyperthyroidism. 
​Symptome:

• Restlessness and nervousness
• Cardiac arrhythmia and palpitations
• Schlafstörungen
• sweating
• weight loss 

Thyroid nodules are initially examined by palpating the thyroid gland, followed by an ultrasound examination and, if necessary, additional scintigraphy. 
Ultrasound can be used to determine the volume of the thyroid gland. In addition, the size and structure of the nodules can be assessed, primarily to clarify whether they are harmless or suspicious.
If this question cannot be clearly answered by ultrasound, proceed as follows:

• Scintigraphy to clarify the presence of a correspondingly “hot” or ‘cold’ nodule. In the case of “cold” nodules and suspicious changes in the ultrasound, a
• Fine needle aspiration. This provides information about the tissue characteristics of the lump and thus indicates whether surgical removal of the lump is necessary. 

Following individual examination, medication is also available to treat such harmless nodules. The aim is to prevent further growth or to reduce the size of the nodule.