🩺Blood Sugar Levels Explained: Fasting, Post-Meal & HbA1c
Confused by fasting sugar, post-meal sugar, and HbA1c? Here's what each number means, the normal ranges, and when it's time to take action.
Dr. Rajesh Patel
Diabetologist
Blood Sugar Levels Explained: Fasting, Post-Meal & HbA1c
India has over 100 million people living with diabetes — and millions more who don't know they're pre-diabetic. Understanding your blood sugar report is one of the most important things you can do for your health.
Let's break down the three key numbers.
The Three Blood Sugar Tests
1. Fasting Blood Sugar (FBS)
This is measured after not eating or drinking anything (except water) for at least 8 hours. Usually done first thing in the morning.
| Level | What It Means |
|---|---|
| Below 100 mg/dL | Normal |
| 100 – 125 mg/dL | Pre-diabetes |
| 126 mg/dL and above | Diabetes |
2. Post-Prandial Sugar (PPS / Post-Meal)
Measured 2 hours after a meal. Shows how your body handles food.
| Level | What It Means |
|---|---|
| Below 140 mg/dL | Normal |
| 140 – 199 mg/dL | Pre-diabetes |
| 200 mg/dL and above | Diabetes |
3. HbA1c (Glycated Haemoglobin)
This is the most important number. It shows your average blood sugar over the past 2–3 months. No fasting needed.
| Level | What It Means |
|---|---|
| Below 5.7% | Normal |
| 5.7% – 6.4% | Pre-diabetes |
| 6.5% and above | Diabetes |
Think of HbA1c as a "quarterly report card" for your blood sugar. A single fasting test is like a snapshot; HbA1c is a video.
Why HbA1c Matters Most
- It can't be "gamed" by fasting or eating well the day before
- It reflects long-term sugar control
- Doctors use it to adjust medications
- Target for diabetics is usually below 7%
Pre-Diabetes: The Warning Sign
If your numbers fall in the pre-diabetes range, it's not diabetes yet — but it's a serious warning. The good news: lifestyle changes can reverse pre-diabetes — studies show a 58% reduction in progression to diabetes.
Many Indians ignore pre-diabetes until it becomes full-blown diabetes. Don't make that mistake.
For a detailed guide on diet, exercise, and lifestyle strategies to manage blood sugar naturally, see our Managing Blood Sugar Naturally Guide.
Common Misconceptions
"I'm not fat, so I can't have diabetes." Wrong. Many Indians are "thin outside, fat inside" (TOFI). You can have diabetes at any weight.
"I don't eat sweets, so my sugar is fine." Sugar isn't the only culprit. White rice, white bread, potatoes, and even fruits can spike blood sugar.
"If I start insulin, I'll be on it forever." Not necessarily. Some people can stop insulin with lifestyle changes. Your doctor will guide you.
How scanura Helps
Upload your diabetes panel to scanura and get:
- Colour-coded flags for fasting, post-meal, and HbA1c
- Plain-language explanation in Hindi and English
- Doctor questions like "Should I start metformin?" or "Do I need an HbA1c retest in 3 months?"
Disclaimer: This article is for educational purposes only. scanura does not provide medical diagnosis. Always consult your doctor for medical decisions.
Medical References
Step-by-Step Guide
- 1
Get fasting blood sugar test
Fast for 8-12 hours (water is okay). Visit a lab in the morning for accurate fasting glucose reading.
- 2
Check fasting glucose level
Below 100 mg/dL is normal. 100-125 is pre-diabetes. 126+ is diabetes.
- 3
Get post-meal sugar test
Eat a meal and test 2 hours after eating. Below 140 mg/dL is normal. 140-199 is pre-diabetes. 200+ is diabetes.
- 4
Check HbA1c
This shows average blood sugar over 2-3 months. Below 5.7% is normal. 5.7-6.4% is pre-diabetes. 6.5%+ is diabetes.
- 5
Monitor regularly
If pre-diabetic, retest every 3-6 months. If diabetic, target HbA1c below 7%.
- 6
Consult your doctor
Discuss results with your diabetologist. Use scanura for instant explanations and doctor questions.