Diabetes

What is Diabetes?
Diabetes is a common condition that occurs when the level of sugar (glucose) in your blood is too high. This happens when your pancreas doesn’t produce enough insulin (or none at all) or when your body doesn’t respond properly to the effects of insulin.
Glucose (sugar) comes from the food and drink we consume, mainly in the form of carbohydrates, and is used by our cells for energy. When glucose enters our bloodstream, insulin helps your cells take up glucose and use it for energy. If your body does not produce insulin or does not respond properly to it, glucose builds up in the blood, causing high levels (hyperglycemia). Over time, this can cause health problems like heart disease, eye issues and nerve damage.
There are several types of diabetes:
- Type 1 diabetes: This is an autoimmune disease. The body’s immune system destroys its insulin producing cells. This is a lifelong condition.
- Type 2 diabetes: The most common type of diabetes in which the body cannot produce enough insulin or does not respond to insulin properly.
- Gestational diabetes: Develops in pregnancy and affects the way your cells use glucose, causing high blood sugar levels.
- Prediabetes: This is when blood glucose levels are higher than normal but not high enough for a diagnosis of Type 2 diabetes. It increases your risk of Type 2.
What are the symptoms of diabetes?
Common diabetes symptoms include:
- Blurred vision
- Feeling thirsty all the time
- Feeling very tired
- Frequent urination
- Weight loss
- Numbness/tingling in the hands or feet.
Type 1 diabetes usually develops quickly, within a matter of weeks or months.
Many people with Type 2 diabetes have no symptoms, or the symptoms develop slowly, meaning they live with the condition for many years before it is diagnosed.
What causes diabetes?
Blood glucose (sugar) is controlled by the hormone insulin, which is produced by the pancreas. When we eat or drink, glucose enters our bloodstream and insulin is released to move the sugar from the blood to our cells for energy.
In people with diabetes, transportation of glucose from our blood to the cells is impaired. This may be because not enough insulin is produced or because the body is not responding to insulin properly.
Type 1 diabetes happens when the body’s immune system attacks insulin-producing cells in the pancreas. This occurs in genetically susceptible individuals and is precipitated by environmental triggers. Lifestyle factors do not cause Type 1 diabetes.
Type 2 diabetes is caused by several factors, including genetics and lifestyle factors such as obesity and physical inactivity. Type 2 diabetes usually begins with insulin resistance which is where the liver, muscle and fat cells don’t respond to insulin properly. This leads to the body needing more insulin – at first the pancreas produces more, but eventually, it cannot make enough, and blood sugar levels increase.
Gestational diabetes is believed to be caused by hormonal changes which take place during pregnancy. Genetics and lifestyle factors may also play a role.
What are the risk factors for diabetes?
Type 1 diabetes is an autoimmune disease with genetic susceptibility and environmental factors involved. There are currently no known lifestyle changes you can make to prevent Type 1 diabetes.
The risk of Type 2 diabetes can be reduced by making lifestyle changes such as losing weight, exercising regularly and eating a healthy diet.
Risk factors for Type 2 diabetes include:
- Being overweight or obese
- Eating an unhealthy, unbalanced diet
- Having a family history of Type 2 diabetes
- Having high blood pressure
- Previously having gestational diabetes in pregnancy
- Taking medications such as steroids for prolonged periods.
What are the possible complications of diabetes?
Diabetes can cause a number of health complications if blood glucose levels aren’t managed properly. These include:
- Stroke
- Coronary artery disease
- Heart attack
- Atherosclerosis
- Neuropathy (Nerve damage)
- Retinopathy (eye damage)
- Nephropathy (kidney damage)
- Skin infections
- Foot complications
- Hearing loss
- Sexual dysfunction.
How is diabetes diagnosed?
Diabetes can be diagnosed with a blood test that measures glucose levels. There are several tests that can measure blood glucose levels:
- HbA1C: Also called the glycated hemoglobin test, this gives your average blood sugar level over the last few months.
- Fasting blood glucose test: This test measures your blood glucose levels after fasting for eight hours, allowing your doctor to see your baseline level, when it is unaffected by food.
- Random blood glucose test: This test can be performed at any time.
- Oral glucose tolerance test (OGTT): A test commonly used to check for gestational diabetes, during which blood is tested after fasting and then again a couple of hours after drinking a glucose liquid.
How is diabetes managed?
Managing diabetes is different for everyone, and your diabetes team will work with you to develop a personalized diabetes management plan. This may involve:
- Blood glucose monitoring: This will provide information on how well your diabetes management is working on a regular basis. This can be done via finger-prick testing or using a continuous glucose monitor.
- Taking oral medication: Several medications can help manage blood glucose levels, depending on the type of diabetes and your individual needs. Metformin is one commonly used medication for Type 2 diabetes.
- Injecting insulin: People with Type 1 diabetes need insulin, and some people with Type 2 diabetes also need insulin to manage their blood glucose levels.
- Making lifestyle changes: Following a healthy diet and increasing physical exercise are important parts of managing diabetes. They can also help to keep your weight within a healthy range, which can reduce the risk of heart disease.
Diabetes is a complex condition, but with proper management and care, you can live a full and healthy life.

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