Diabetes mellitus is a disorder in which blood glucose levels remain abnormally high because the body either produces insufficient insulin or cannot use insulin effectively. This causes excessive thirst, frequent urination, fatigue, and long-term damage to the eyes, kidneys, nerves, and blood vessels.

Hyperthyroidism occurs when the thyroid gland produces excessive thyroxine. It speeds up metabolism, leading to weight loss, rapid heartbeat, excessive sweating, nervousness, and heat intolerance.

Hypothyroidism develops when the thyroid gland produces too little thyroxine. It slows metabolism, causing tiredness, weight gain, dry skin, constipation, and sensitivity to cold.

Goiter is an abnormal enlargement of the thyroid gland. It commonly results from iodine deficiency or thyroid disorders and appears as swelling in the front of the neck.

Gigantism is caused by excessive secretion of growth hormone during childhood before the growth plates close. It results in unusually rapid growth and extremely tall stature.

Growth hormone deficiency during childhood may cause pituitary dwarfism. Affected individuals have proportionate body parts but grow much shorter than average.

Cushing syndrome occurs when the body is exposed to excessive cortisol. Symptoms include weight gain around the abdomen and face, muscle weakness, high blood pressure, and thinning skin.

Addison disease results from insufficient production of cortisol and aldosterone by the adrenal glands. It causes fatigue, low blood pressure, weight loss, and darkening of the skin.

Acromegaly develops when excessive growth hormone is produced in adulthood. Since bones can no longer grow longer, the hands, feet, jaw, and facial bones become enlarged.

Insulin resistance occurs when body cells do not respond properly to insulin. The pancreas produces more insulin to compensate, increasing the risk of developing Type 2 diabetes.

PCOS is a hormonal disorder affecting females. It may cause irregular menstrual cycles, ovarian cysts, acne, excessive hair growth, infertility, and insulin resistance.

Reduced melatonin production or disruption of the body's biological clock can cause insomnia, poor sleep quality, daytime fatigue, and disturbed sleep cycles.

Chronic stress causes prolonged release of cortisol and adrenaline. Persistently high levels may weaken immunity, raise blood pressure, disturb sleep, and increase the risk of anxiety and depression.

When the pituitary gland produces too little growth hormone, children may experience slow growth, delayed physical development, and reduced height compared with their peers.

Hormonal imbalance refers to having too much or too little of one or more hormones. Depending on the affected hormone, it can influence growth, metabolism, mood, reproduction, sleep, and overall health.