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Diabetes Mellitus

What is Diabetes?

Diabetes mellitus, also known as diabetes, is a chronic metabolic disease characterised by abnormally high blood sugar levels. It is caused by a disorder of the pancreas, which produce insulin, the main hormone that converts glucose from food into energy. A decrease in insulin production causes glucose to stay in the blood, causing blood sugar levels to rise. This rise leads to the condition, which can be Type 1 diabetes or Type 2 diabetes.

What are the types of Diabetes?

Type 1 diabetes takes place when the immune system destroys the insulin-producing cells in the pancreas. The insulin which is no longer produced by the body is administered through daily injections on a life-long basis.

Type 2 diabetes is the most common type of diabetes that is usually caused by weight and lifestyle-related issues. It happens when the body is unable to produce enough insulin. It could also be a condition called insulin resistence when the body does not react to the insulin produced. Type 2 diabetes is less severe but remains a progressive disease that worsens over time. It is also linked to obesity where there isn't enough insulin to break the blood glucose down.

Diabetes is a life-long condition without a cure and its symptoms are managed through lifestyle adjustments. It needs constant monitoring of blood glucose levels to prevent the worsening of this disease.

Gestational diabetes occurs during pregnancy and develops when blood glucose levels increase during pregnancy. It usually resolves itself and insulin production goes back to normal after childbirth. It is important to control blood glucose levels as the condition may be passed to the child.

Prediabetes is a condition where blood sugar levels are higher than normal, but not at a point to warrant a Type 2 diabetes diagnosis. The condition can be reversed with appropriate lifestyle interventions such as regular exercise and a healthy diet.

What are the symptoms of Diabetes?

  • Blurred vision
  • Constant hunger
  • Fatigue and tiredness
  • Frequent urination
  • Increased thirst
  • Irritability
  • Slow-healing wounds
  • Weight loss

How is Diabetes diagnosed?

Blood Tests

Glycated haemoglobin (HbA1C) test
HbA1C reflects the average blood sugar level for the past two to three months and measures the amount of haemoglobin in the blood that has glucose attached to it. It does not require fasting and 2 separate tests are conducted to determine the presence of diabetes.
An HbA1C level of 6.5 percent or higher on two separate tests indicates that you have diabetes. An HbA1C between 5.7 and 6.4 percent indicates prediabetes. Below 5.7 is considered normal.

Random blood sugar test
A random blood sugar level of 200 milligrams per deciliter (mg/dL) — 11.1 millimoles per liter (mmol/L) — or higher suggests diabetes.

Fasting blood sugar test
A blood sample is taken after an overnight fast and a level less than 100 mg/dL (5.6 mmol/L) is normal. A fasting blood sugar level from 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is considered prediabetes. If it's 126 mg/dL (7 mmol/L) or higher on two separate tests, you have diabetes.

Oral glucose tolerance test
An overnight fast is required, after which the fasting blood sugar level is measured. A sugary liquid is taken, and blood sugar levels are tested periodically for the next two hours.

A blood sugar level less than 140 mg/dL (7.8 mmol/L) is normal. A reading of more than 200 mg/dL (11.1 mmol/L) after two hours indicates diabetes. A reading between 140 and 199 mg/dL (7.8 mmol/L and 11.0 mmol/L) indicates prediabetes.

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