Diabetes mellitus is one of the most commonly seen conditions. The statistics of diabetes in the United States are alarming to say the least - 8 % of the population suffers from this type of diabetes. This is a long-term disease whose symptoms include uncontrollable hunger or thirst, wounds that cease to heal, considerable amount of weight loss or gain, frequent urination, etc. Sedentary lifestyle, alcoholism, smoking can be a few factors responsible for this condition. Basically, diabetes is of two types, type 1 diabetes and type 2 diabetes, both of which differ in their etiologies.

Etiology of Type 1 Diabetes

Type 1 diabetes is also known as childhood diabetes, insulin dependent diabetes mellitus, or juvenile diabetes. This is a type of diabetes mellitus that occurs due to the autoimmune destruction of the insulin producing beta cells of the pancreas.

The exact etiology of diabetes mellitus of this kind is not fully understood. It is said that immunological factors, along with genetic and environmental factors are the cause behind these symptoms in childhood. This is in fact a polygenic disease, that is, many different genes contribute to its expression. The strongest gene, IDDM1, is located in the MHC class-II region on chromosome number 6, at staining region 6p21. This is believed to be responsible for the histocompatibility disorder that is characteristic of type 1 insulin-producing beta cells in the pancreas that display improper antigens to T cells. The etiology of diabetes can also include strong environmental factors, as it has been seen that this strongly influences the expression of type 1 diabetes.

Etiology of Type 2 Diabetes

Diabetes mellitus that affects people in adulthood is known as type 2 diabetes, non-insulin dependent diabetes, or adult onset diabetes. This is a disorder that is characterized by high levels of glucose in the blood that occurs due to an increase in the resistance of the body to insulin.

There are many factors that can lead to diabetes mellitus, or at least that can exacerbate this type of diabetes. These factors include obesity (around 55 percent of type 2 diabetes patients are obese at diagnosis), high blood pressure, elevated cholesterol along with hyperlipidemia and with the condition often termed metabolic syndrome. Other causes include acromegaly, Cushing's syndrome, thyrotoxicosis, pheochromocytoma, chronic pancreatitis, and the use of certain drugs. Additional factors found to increase the risk of type 2 diabetes include aging and a diet that is high in fats along with a sedentary lifestyle. Chronic obesity leads to increased insulin resistance that can develop into type 2 diabetes, most likely because adipose tissue especially that in the abdominal region and around internal organs could be a source of several chemical signals to other tissues like hormones and cytokines.

There is also a possibly strong inheritable genetic connection in type 2 diabetes. It has been seen that having relatives that have type 2 diabetes increases the risk of developing type 2 diabetes substantially. In addition, there is also a mutation to the Islet Amyloid Polypeptide gene that results in an earlier onset, which is a more severe, form of diabetes. However, environmental factors like diet, weight, and lifestyle play a large part in the development of type 2 diabetes, in addition to any genetic component.

There are also many medications that can lead to the chronic onset and development of diabetes. These include atypical anti-psychotic drugs, beta blockers, calcium channel blockers, DPP-4 inhibitors, Sulfonylureas, Metformin, Meglitinides, thiazide diuretics, etc. There are different mechanisms by which these drugs can lead to an increase in the insulin resistance in the body.

Diabetes mellitus is a serious condition that affects practically every organ and system in the body. Furthermore, high levels of glucose in the blood increases the susceptibility of a person to contract an infection and also delays wound healing. Hence, a person who is suffering from diabetes mellitus must make all possible efforts and lifestyle changes so as to keep a check on his blood sugar levels.