Diabetes: Overview, Symptoms, Causes, Prevention, and Treatment

Understanding Diabetes

What Is Diabetes?

Diabetes is a chronic condition that affects how your body converts food into energy. Normally, your pancreas releases insulin — a hormone that helps move sugar (glucose) from your bloodstream into your cells for energy. With diabetes, your body either doesn’t make enough insulin or can’t use it effectively. This leads to high blood sugar levels, or hyperglycemia.

There are two main types: Type 1 (autoimmune) and Type 2 (insulin resistance). Both require ongoing care to prevent complications.

According to the Centers for Disease Control and Prevention (CDC), more than 38 million Americans have diabetes, and about 1 in 5 don’t know they have it.

Types of Diabetes

  • Type 1 Diabetes: An autoimmune disease where the immune system destroys insulin-producing cells in the pancreas. Learn more about T1D.
  • Type 2 Diabetes: The most common type, where your body becomes resistant to insulin. Learn more about T2D.
  • Gestational Diabetes: Develops during pregnancy and usually resolves after birth but increases future risk of T2D.

Common Symptoms of Diabetes

Symptoms vary, but common signs include (Mayo Clinic):

  • Increased thirst and frequent urination
  • Extreme hunger
  • Fatigue and weakness
  • Blurred vision
  • Unexplained weight loss
  • Slow-healing sores or frequent infections
  • Numbness or tingling in hands or feet

What Causes Diabetes?

Diabetes has several underlying causes, depending on the type:

  • Type 1: Autoimmune destruction of beta cells in the pancreas (NIH).
  • Type 2: The body becomes resistant to insulin due to lifestyle, genetics, and other factors.
  • Gestational: Hormonal changes during pregnancy cause temporary insulin resistance.

Risk factors include obesity, inactivity, poor diet, family history, and age over 45.

Diagnosis

Diagnosis involves simple blood tests to measure glucose levels (ADA):

  • A1C Test: Measures average blood sugar over 2–3 months. Try our A1C Calculator.
  • Fasting Blood Sugar Test: Checks blood sugar after an overnight fast.
  • Oral Glucose Tolerance Test: Measures your body’s response to sugar intake.
  • Random Blood Sugar Test: Can detect diabetes at any time of day.

Treatment and Management

There’s no cure for diabetes, but it can be managed with the right care plan. Treatment depends on the type but typically includes:

1. Medication

  • Insulin therapy for Type 1 and some Type 2 patients.
  • Oral medications like metformin for Type 2 diabetes.

2. Blood Sugar Monitoring

Tracking glucose levels helps you adjust your medication, diet, and exercise.

3. Nutrition

Healthy eating plays a key role in managing diabetes. Explore our Diets and Nutrition guide for meal planning tips.

4. Exercise

Regular activity improves insulin sensitivity and blood sugar control. Visit our Exercise section for safe workouts and advice.

Prevention

While Type 1 diabetes isn’t preventable, Type 2 and gestational diabetes can often be delayed or avoided with lifestyle changes (CDC):

  • Maintain a healthy weight
  • Exercise regularly (at least 150 minutes per week)
  • Eat balanced meals rich in fiber, fruits, and vegetables
  • Avoid sugary drinks and processed foods
  • Monitor blood sugar if you’re at risk

Living with Diabetes

With proper care, people with diabetes can live long, fulfilling lives. Focus on consistency in diet, activity, and monitoring, and build a relationship with your care team. The CDC and ADA provide excellent guidance on daily management.

Frequently Asked Questions (FAQ)

Type 2 diabetes can sometimes be put into remission through diet, exercise, and weight loss (Mayo Clinic).

For most adults, fasting blood sugar should be below 100 mg/dL, and A1C under 7% (ADA).

It depends on your treatment plan. People on insulin often check multiple times daily; others may only need periodic monitoring.

References

Reviewed by Dr. Seshadri Das, Endocrinologist
Written by Diabetesknow Research Team
Last updated: December 2025