📖 Diabetes Basics: Understanding Types, Symptoms & Diagnosis
A complete, doctor‑reviewed guide to the fundamentals of diabetes — by Dr. Ravi Sishir Reddy, MD
Medically reviewed by: Dr. Ravi Sishir Reddy, MBBS, MD (General Medicine)
Last updated: [Insert Date] | All content in this pillar is reviewed by Dr. Reddy.
📊 Key Numbers You Should Know
- Normal fasting glucose: Below 100 mg/dL (5.6 mmol/L)
- Prediabetes (impaired fasting glucose): 100–125 mg/dL (5.6–6.9 mmol/L)
- Diabetes: Fasting ≥126 mg/dL (7.0 mmol/L) on two occasions
- HbA1c normal: Below 5.7%
- HbA1c prediabetes: 5.7%–6.4%
- HbA1c diabetes: ≥6.5%
Diabetes is a condition that affects how your body turns food into energy. It sounds simple, but the details matter — especially when you’re newly diagnosed and trying to understand what it all means. This pillar guide, reviewed by Dr. Ravi Sishir Reddy, walks you through the fundamentals: what diabetes actually is, the differences between its types, how it’s diagnosed, and what your lab reports are telling you.
In This Guide:
- What is Type 2 Diabetes?
- Type 1 vs Type 2 Diabetes
- Prediabetes: Symptoms & Reversal
- Insulin Resistance Explained
- Blood Sugar Levels: Normal Range
- HbA1c Test Explained
- Fasting vs Postprandial Sugar
- Glucose Tolerance Test (OGTT)
- Risk Factors You Can Control
- Genetics & Family History
- Diabetes in Young Adults (India)
- Gestational Diabetes Overview
- LADA: Latent Autoimmune Diabetes
- Diabetes Myths Debunked
1. What is Type 2 Diabetes?
Type 2 diabetes is a chronic condition where the body either resists the effects of insulin — the hormone that moves sugar from the blood into cells — or doesn’t produce enough insulin to maintain normal glucose levels. It accounts for 90‑95% of all diabetes cases and is strongly linked to lifestyle and genetics.
👉 Read more: What is Type 2 Diabetes? →
2. Type 1 vs. Type 2 Diabetes: What’s the Difference?
Though both involve high blood sugar, the underlying causes are very different. Type 1 is an autoimmune destruction of insulin‑producing beta cells; Type 2 is primarily insulin resistance. Treatment, onset, and risk factors differ significantly.
👉 Read more: Type 1 vs Type 2 →
3. Prediabetes: Symptoms & Reversal
Prediabetes is a warning zone where blood sugar is elevated but not yet in the diabetic range. It is reversible with lifestyle changes — weight loss, diet, and exercise — and acting at this stage can prevent progression to full diabetes.
4. Insulin Resistance Explained
Insulin resistance is the root cause of Type 2 diabetes. It means your cells don’t respond well to insulin, forcing the pancreas to produce more and more until it eventually wears out.
👉 Read more: Insulin Resistance →
5. Blood Sugar Levels: Normal Range
Understanding target ranges for fasting, postprandial, and random glucose is the foundation of self‑management. This article breaks down the numbers for non‑diabetics, prediabetics, and diabetics.
👉 Read more: Blood Sugar Levels →
6. HbA1c Test Explained
The HbA1c test reflects your average blood sugar over the past 2‑3 months. It’s the most important number for tracking long‑term control and guiding treatment decisions.
7. Fasting Blood Sugar vs. Postprandial
Fasting sugar tells you how your body regulates glucose overnight; postprandial sugar shows how it handles a meal. Both are needed for a complete picture.
👉 Read more: Fasting vs Postprandial →
8. Glucose Tolerance Test (OGTT)
The OGTT is the definitive test for diagnosing gestational diabetes and borderline cases. You drink a glucose solution, and blood samples are taken over 2 hours.
9. Diabetes Risk Factors You Can Control
While age and genetics play a role, obesity, sedentary lifestyle, poor diet, and smoking are modifiable risks. Addressing these can prevent or delay diabetes.
👉 Read more: Controllable Risk Factors →
10. Genetics and Diabetes: Family History
A strong family history increases your risk, but it doesn’t make diabetes inevitable. Understanding your genetic susceptibility helps you take early preventive action.
👉 Read more: Genetics & Diabetes →
11. Diabetes in Young Adults in India
Alarmingly, Type 2 diabetes is rising sharply among Indians under 40. This article discusses the unique drivers — central obesity, high‑carb diets, and genetic predisposition — and how young adults can fight back.
👉 Read more: Young Adult Diabetes →
12. Gestational Diabetes Overview
Diabetes that develops during pregnancy requires careful management to protect both mother and baby. Most cases resolve after delivery, but they increase the future risk of Type 2 diabetes.
👉 Read more: Gestational Diabetes →
13. Latent Autoimmune Diabetes in Adults (LADA)
LADA is a slowly progressive form of autoimmune diabetes that looks like Type 2 initially but eventually requires insulin. It’s often misdiagnosed. Learn the clues.
14. Diabetes Myths Debunked
From “eating too much sugar causes diabetes” to “insulin means you’ve failed” — we separate fact from fiction.
Armed with the basics, you’re ready to take control. Browse the articles above to build your understanding, and always involve your doctor in decisions about your health.
📋 Medical Disclaimer
This article is for educational purposes only and does not substitute for professional medical advice. All content is reviewed by Dr. Ravi Sishir Reddy. Consult your physician for diagnosis and treatment of diabetes.