Diabetes Mellitus :

Diabetes Mellitus is a syndrome characterized by a metabolism disorder and abnormal increase in the blood sugar level resulting due to an insufficient level of the hormone insulin. 

Diabetes is a disorder characterized by hyperglycemia or high blood glucose level. Diabetes mellitus is often referred to a group of metabolic diseases characterized by high blood sugar levels, which result from defects in insulin secretion, or action, or both. 

Diabetes mellitus, commonly known as diabetes was first identified as a symptom associated with “sweet urine," and excessive muscle loss. High levels of blood glucose lead to the excretion of glucose in the urine, hence the phrase “sweet urine”. 

Though it cannot be cured after it occurrence, it can be kept well under control with a proper medication, diet and exercise.

Normally, blood sugar levels are controlled by insulin. Insulin is released from the pancreas to normalize the glucose level when the blood glucose is high. 

In patients with diabetes, the absence of insulin causes hyperglycemia. The two principal classifications of Diabetes Mellitus are Types 1 and 2. The “type 1 Diabetes" has globally replaced the former terms, including childhood-onset diabetes, juvenile diabetes, and insulin-dependent diabetes (IDDM). 

Similarly, the term "type 2 Diabetes" has replaced several former terms, including adult-onset diabetes, obesity-related diabetes, and non-insulin-dependent diabetes

(NIDDM).