Detailed answer

While dark spots on the skin are often harmless and can be caused by sun damage or aging, in some cases, they may be a sign of an underlying internal disease. Certain medical conditions like liver disease, diabetes, and hormonal disorders can cause hyperpigmentation or darkening of the skin. Dark spots that are accompanied by other symptoms such as fatigue, weight loss, or changes in bowel habits should be evaluated by a healthcare professional. It is important to keep in mind that dark spots alone do not necessarily indicate an internal disease and a proper medical diagnosis is crucial for accurate identification of the cause.