Diabetes mellitus or diabetes is a metabolism disorder taking place due to a combination of environmental and hereditary reasons. And the result of it is unusually high levels of sugar in the blood. The blood sugar levels in our bodies are balanced by an interaction of multiple chemicals and hormones, including the insulin hormone, which found in the pancreas. As a result of some defect in the action of insulin or problem in insulin secretion the blood sugar level increases. Hyperglycemia occurs that leads to the acute signs of diabetes like too much urine production, thirst and increased fluid intake, blurred vision, mysterious weight loss, lethargy and changes in energy metabolism.

The symptoms of diabetes occur gradually and are hard to identify initially. These may include a sick feeling, fatigue, excessive thirst and frequent urination, especially at night. Since the body has extra glucose in the blood, it tries to get rid of it through urine. This fluid loss leads to a feeling of thirst. Among the other symptoms are blurred vision, sudden weight loss, genital itching and slow healing of gum, skin and urinary tract infections. Since blood sugar is not something that one can see, the side effects are the signs that are considered by the doctors. Seeing the symptoms, the blood sugar level of the body is tested and accordingly, diabetes is diagnosed.

Doctors often suspect diabetes if the patient develops certain health problems that are related to diabetes. Heart disease, changes in vision, numbness in the feet and legs or slow-healing sores prompt a doctor to check for diabetes. These symptoms do not necessarily mean diabetes but anyone having any of these problems needs to consult a doctor as a preventive measure. Once the diabetes gets treated, the symptoms diminish.

Polyuria (frequent urination), polydipsia (excessive thirst) and polyphagia (hunger and weight loss) are the classic symptoms of diabetes. A dry mouth, aches and pains, fatigue, unusual infections, blurred vision, dry skin and slow healing of wounds are the other signs. But one needs to remember that not everybody will show all of these symptoms. It is better to test one's blood sugar level if any one of these symptoms occurs. Sometimes, there can be absolutely no symptoms and yet, one can have diabetes.

In diabetes type 1, the pancreas stops producing insulin due to some viral attack or autoimmune response. In the absence of insulin, body cells don't get the required amount of glucose for producing Adenosin Triphosphate or ATP units. This results in the symptom of nausea and vomiting. Gradually, the body starts breaking down the muscle tissue and fat for producing energy leading to weight loss. Due to electrolyte disturbance dehydration can also occur. Advanced stages of diabetes can lead to coma and death.

In case of diabetes type 2, the body builds up a resistance to insulin. Due to the failure of the cells to metabolise glucose, fat deposited in the body is metabolised to gain energy. The body undergoes negative calorie effect and feels fatigue. When the glucose concentration in the blood rise, the brain receives signal for diluting it. Hyperosmolar hyperglycemia nonketotic syndrome results as body fluid is pulled out of tissues together with eye lenses.