Diabetes mellitus is a chronic disease in which patients present with absolute or relative insulin deficiency. It affects about 6% of western populations and is a major contributing factor for heart attacks, strokes, kidney failure and peripheral vascular disease. Diabetes mellitus is also the leading cause of new blindness without a cure.

1. Types of Diabetes
There are four forms of the disease, classified as: types 1 and 2, gestational and other specific types.

a. Type 1 Diabetes
In people with type 1 diabetes the pancreas is not producing insulin, so blood glucose levels are higher than normal. People with this form of diabetes require daily insulin therapy to survive. This form is further split into idiopathic diabetes and immune mediated diabetes.

Type 1 accounts for around 10% to 15% of all people with diabetes. It is one of the most serious and common chronic diseases of childhood, with about half of the people with this form of diabetes developing the disease before age 18. It is also known as insulin dependent diabetes mellitus (IDDM) or juvenile-onset diabetes.

b. Type 2 Diabetes
Type 2 diabetes is marked by reduced levels of insulin (insulin deficiency) and/or the inability of the body to use insulin properly (insulin resistance). This form of the disease is most common among people aged 40 years and over and accounts for 85% to 90% of all people with diabetes. Most people with type 2 diabetes are obese.

c. Gestational Diabetes
Gestational diabetes occurs during pregnancy in about 3% to 8% of females not previously diagnosed with diabetes. It is a temporary form of diabetes and usually disappears after the baby is born. However, it is a marker of much greater risk of developing Type 2 diabetes later in life. Screening tests for gestational diabetes are usually performed around the 24th-28th week of pregnancy.

d. Other Specific Diabetes Types
This includes people who have diabetes as a result of a genetic defect, or exposure to certain drugs or chemicals.

2. Causes of Diabetes Mellitus
Diabetes is caused by resistance to, or deficient production of, the hormone insulin, which helps glucose move from the blood into the cells.

In type 1 immune mediated diabetes, pancreatic beta cell destruction results in failure to release insulin and ineffective transport of glucose. There is no known cause for idiopathic diabetes.

In type 2 diabetes, the beta cells release insulin but, receptors are insulin resistant and glucose transport is variable and inefficient. Some people may have conditions that can cause diabetes, such as Cushing's syndrome, pancreatitis or liver disease.

Risk factors for type 2 diabetes include;

a. Obesity
b. History of Gestational diabetes
c. Lack of physical activity
d. Hypertension
e. Age 45+
f. Ethnic groupings other than anglo-saxon
g. Low HDL cholesterol levels
h. Impaired glucose tolerance
i. Family history

3. Signs and Symptoms of Diabetes
Symptoms of diabetes include; dehydration, unexplained weight loss, excessive thirst, frequent need to urinate, fatigue, lethargy, severe irritation and itching, excessive hunger, blurred vision, skin and urinary infections and vaginitis.

4. Diagnosis
Diabetes or impaired glucose tolerance may be detected on routine blood tests as part of a general health check up or investigation for other symptoms or diseases. Diabetes tests check blood glucose levels. Someone with a random non fasting blood glucose level greater than 200mg/dl accompanied by other symptoms, or someone with a fasting blood glucose level greater than 126mg/dl can be diagnosed with diabetes.

Because symptoms can be mild, diabetes is often detected when a person suffers a problem that is caused by diabetes, such as a heart attack, stroke, neuropathy, poor wound healing or a foot ulcer, certain eye problems, certain fungal infections, or delivering a baby with macrosomia or hypoglycemia.

5. Diabetes Treatment
Effective treatment endeavors to normalize blood glucose and reduce complications using insulin replacement, diet and exercise. For those with very mild diabetes, diet plus weight loss plus exercise may be enough to keep blood glucose within reasonable levels.
Dietary changes should focus on the ideas of weight loss and blood sugar regulation by keeping the blood sugar levels relatively stable throughout the day, avoiding big peaks or troughs.

The principal treatment of type 1 diabetes, even from its earliest stages, is replacement of insulin combined with careful monitoring of blood glucose levels using blood testing monitors.

Type 2 diabetes may require oral anti-diabetic drugs to stimulate the body's insulin production and increase insulin sensitivity. Various forms of natural supplements for diabetes treatment have also been postulated as effective.

People with unstable diabetes, or those requiring many injections a day, may benefit from an insulin pump which is worn on the body and delivers a continuous infusion of insulin via a needle implanted into the body.

Gestational diabetes is fully treatable but requires careful medical supervision throughout the pregnancy. Even though it may be transient, untreated gestational diabetes can damage the health of the fetus or the mother.

Treatment for all forms of diabetes need not significantly impair normal activities, if sufficient patient training, awareness, appropriate care, discipline in testing and dosing of insulin is taken

6. Complications
Diabetes mellitus is the most common cause of adult kidney failure worldwide in the developed world. If undetected or poorly controlled, diabetes can lead to blindness, kidney failure, lower limb amputation, heart attack, stroke and impotence.