Diabetes mellitus is a common condition characterized by high blood glucose (sugar) levels. Blood glucose levels are regulated by a hormone called insulin, which is produced by the pancreas gland. Diabetes develops when there is insufficient production of insulin or when the body’s tissues become resistant to normal or even high levels of insulin, or a combination of both of these problems.
Diabetes is a chronic medical condition requiring regular monitoring and treatment. Treatment can effectively control blood glucose levels and minimize a person’s risk for the complications of diabetes. Lifestyle adjustments and self-care also play a large role in the treatment of diabetes over time.
What are the different types of diabetes?

Diabetes is classified as either type 1 or type 2 diabetes.
Type 1 diabetes
Type 1 diabetes usually begins in childhood or young adulthood, but can occur at any age. This type of diabetes occurs when the pancreas produces very little insulin or no insulin at all. This is a serious condition and people with type 1 diabetes have to take insulin regularly, and if they do not, they develop a life threatening condition called diabetic ketoacidosis.
Type 2 diabetes
Type 2 diabetes begins in adolescence or adulthood. This type of diabetes occurs when the body’s tissues respond poorly to normal or even high levels of insulin (called insulin resistance). In addition to insulin resistance, insufficient production of insulin by pancreas is also responsible. Insulin treatment may not be necessary, and patients rarely develop diabetic ketoacidosis. However, people with type 2 diabetes often need to take oral medications and follow special diets to lower their blood glucose levels.
Gestational diabetes
Gestational diabetes refers to diabetes that develops during pregnancy.
Impaired glucose tolerance
Impaired glucose tolerance is characterized by borderline elevations of blood glucose. Many people with impaired glucose tolerance eventually develop type 2 diabetes, and people with this condition have an increased risk for cardiovascular disease even if they do not develop diabetes. Impaired glucose tolerance is very common.
Some people with diabetes have
->Excessive thirst
->Excretion of large quantities of urine
->Weight loss
->Blurred vision
However, many people with diabetes have no symptoms at all.

The diagnosis of diabetes is based on the symptoms noted during a medical history and physical examination and on the results of laboratory tests.
Random blood glucose test
Blood glucose can be measured at any time throughout the day, regardless of when a person last ate. A random blood glucose level of 200 mg/dL or higher suggests the presence of diabetes.
Fasting blood glucose test
Measurement of blood glucose test after a person has fasted for 8 to 12 hours (usually overnight) is the most accurate test for diagnosing diabetes. A level of less than 110 mg/dL is considered normal. A level of 126 mg/dL or higher suggests that a person has diabetes. A level between 111 and 125 mg/dL suggests impaired glucose tolerance.
Hemoglobin A1c test
Normal values for hemoglobin A1c are usually 6 percent or lower. This test is most useful for monitoring blood glucose in people with known diabetes.
Certain factors are helpful for identifying people who are likely to develop type 2 diabetes, although some people with these risk factors never develop diabetes.
Impaired glucose tolerance – People with impaired glucose tolerance have an increased risk of type 2 diabetes and an increased risk of cardiovascular diseases such as coronary artery disease
Obesity – For people of all ages, the risk of developing impaired glucose tolerance or type 2 diabetes increases with increasing body weight, which makes the body’s tissues less responsive to insulin. Conversely, weight loss decreases the risk of type 2 diabetes in obese people, and weight loss can improve blood glucose control in people who already have type 2 diabetes.
Gestational diabetes – Women who develop diabetes during pregnancy have an increased risk of developing type 2 diabetes. The results of an oral glucose tolerance test 4 to 16 weeks after delivery help predict the risk over the subsequent 5 years. In one study of women who developed gestational diabetes, 84 percent of women with an abnormal test result (impaired glucose tolerance) developed type 2 diabetes, compared with 12 percent of women with a normal test result.
Three strategies may prevent type 2 diabetes: exercise, weight loss, and drug therapy.
Exercise – Regular exercise can decrease a person’s risk for developing type 2.
Weight loss
Sustained weight loss can improve control of blood sugars. In those with impaired glucose tolerance, sustained weight loss can improve glucose tolerance and prevent progression to type 2 diabetes.
Changing the diet
Doctors may recommend different kinds of dietary changes for people with diabetes, depending upon the type of diabetes and the individual goals of therapy. These changes can promote weight loss, improve blood glucose control, lower blood cholesterol levels, and, indirectly, blood pressure.