Diabetes is a chronic metabolic disorder marked by elevated blood glucose (or blood sugar) levels arising when the body cannot produce enough insulin, or cannot use insulin effectively. Over time, uncontrolled diabetes damages vital organs, including the heart, blood vessels, kidneys, nerves, and eyes.
What Is Diabetes?
According to the World Health Organization (WHO), diabetes results from defects in insulin secretion, insulin action, or both. Insulin is a hormone made by the pancreas that allows glucose to enter cells and be used for energy. When this process breaks down, glucose accumulates in the bloodstream.
Left unaddressed, elevated glucose can injure small blood vessels and nerves, leading to cardiovascular disease, kidney failure, neuropathy, and blindness.
Types of Diabetes
There are several types of diabetes, but the three most common are Type 1, Type 2, and gestational diabetes.
- Type 1 Diabetes
In Type 1 diabetes, the immune system attacks and destroys the insulin-producing beta cells in the pancreas, causing little or no insulin production. It’s sometimes called “insulin-dependent” or “juvenile” diabetes, though it can develop at any age. Without insulin treatment, Type 1 diabetes can lead to life-threatening problems. - Type 2 Diabetes
This is the most common form. It develops when the body becomes resistant to insulin or does not produce enough. Type 2 diabetes often develops gradually and may remain undiagnosed for years. Lifestyle factors such as poor diet, physical inactivity, and obesity are key contributors. - Gestational Diabetes
Gestational diabetes occurs during pregnancy and usually resolves after delivery. However, it increases the risk of future Type 2 diabetes for both mother and child.
Early Signs and Symptoms of Diabetes
Recognizing the early signs of diabetes can prompt timely diagnosis and treatment, which helps prevent long-term complications. Symptoms may vary in intensity, and some people especially with Type 2 or prediabetes may have very subtle or no outward signs.
Here are common early warning signs:
- Increased Thirst and Frequent Urination: Higher blood sugar levels cause more fluid to be filtered through the kidneys, leading to dehydration and more trips to the bathroom.
- Unintended Weight Loss: Without enough insulin, the body breaks down fat and muscle for energy.
- Extreme Hunger: Cells can’t access the glucose in the blood, so the body signals for more food.
- Fatigue or Weakness: Glucose isn’t being used effectively, leaving you feeling drained.
- Blurred Vision: High blood sugar can change the shape of the eye’s lens, affecting focus.
- Slow-Healing Sores and Frequent Infections: High glucose impairs white blood cell function and microcirculation, making infections more common and wounds harder to heal.
- Tingling or Numbness in Hands or Feet: Elevated blood sugar can damage nerves, a condition known as neuropathy.
In Type 1 diabetes, symptoms typically appear suddenly and may include the presence of ketones (a byproduct from the breakdown of fat and muscle) in the urine.
How Is Diabetes Diagnosed?
Healthcare providers use several tests to diagnose diabetes:
- Fasting Plasma Glucose (FPG): Measures blood sugar after an overnight fast.
- Oral Glucose Tolerance Test (OGTT): Measures blood sugar before and two hours after ingesting a glucose drink.
- Hemoglobin A1c (HbA1c): Reflects average blood glucose over the past two to three months.
Diagnostic criteria vary slightly by guideline, but reference values include a fasting glucose ≥ 7.0 mmol/L (126 mg/dL) or a 2-hour OGTT result ≥ 11.1 mmol/L (200 mg/dL), However Hba1C (glycated hemoglobin) is now the favored method of diagnosis based on WHO and regional guidelines.
Can Diabetes Be Prevented?
Prevention depends largely on the type:
- Type 1 Diabetes: Currently, there are no proven ways to prevent Type 1 diabetes.
- Type 2 Diabetes: Many cases can be delayed or prevented through lifestyle changes. Key strategies include:
- Maintaining a healthy weight
- Engaging in regular physical activity (e.g., 150 minutes of moderate aerobic exercise per week)
- Eating a balanced, fiber-rich diet with whole grains, vegetables, and fruit
- For some individuals with prediabetes, medications like metformin may offer additional risk reduction.
- Gestational Diabetes: Risk can be lowered by healthy weight gain during pregnancy, physical activity, and balanced nutrition. After delivery, regular monitoring is important, since risk of progression to Type 2 diabetes remains.
Why Early Detection Matters
Early diagnosis improves long-term outcomes. When diabetes is identified before complications arise, interventions such as blood glucose control, blood pressure and lipid management, and routine screenings for kidney, eye, and nerve damage are more effective.
Emerging Developments
Recent research highlights the use of advanced tools to improve early detection of Type 2 diabetes. For example, a new multimodal neural network model called ECG-DiaNet integrates electrocardiogram (ECG) data with clinical risk factors to predict diabetes risk more accurately. In parallel, other machine learning models are being developed to stratify risk and support early interventions.
Understanding diabetes types, recognizing early symptoms, and engaging in preventive behaviors form the cornerstone of effective care. Although we cannot yet prevent Type 1 diabetes, many cases of Type 2 diabetes are avoidable through healthy lifestyle choices. For healthcare practitioners, promoting screening and early intervention remains critical to reducing the burden of diabetes and protecting patients from its long-term complications.
FAQs
Q: Can someone have diabetes without any symptoms?
Yes. Especially in Type 2 diabetes or prediabetes, symptoms can be mild or absent. That is why periodic screening is crucial, particularly in high-risk individuals.
Q: How often should someone be tested for diabetes?
Testing frequency depends on risk factors such as family history, obesity, or previous gestational diabetes. Many guidelines suggest at least annual screening for high-risk individuals.
Q: Can lifestyle changes reverse prediabetes?
Evidence shows that weight loss, dietary improvements, and regular physical activity can delay or even prevent the onset of Type 2 diabetes in people with prediabetes.
Q: Why is managing blood pressure and lipids important in diabetes?
High blood sugar damages blood vessels over time. Controlling blood pressure and cholesterol helps reduce the risk of cardiovascular disease and other organ damage.