One fact I always tell my patients: type 2 diabetes does not appear suddenly. There is a long period — anywhere from 5 to 10 years — during which the body is already sending warning signals in the form of prediabetes and insulin resistance. Most people pass right through it because there are no obvious symptoms.
What Is Insulin Resistance?
Normally, insulin acts like a "key" that unlocks the body's cells so glucose can enter and be used as energy. With insulin resistance, the body's cells start becoming "unresponsive" to that key — the pancreas has to produce more and more insulin to keep blood glucose levels normal.
Over time, the pancreas becomes "exhausted" and can no longer compensate. That is when blood sugar starts rising permanently — prediabetes turns into type 2 diabetes.
Early Signs That Are Often Overlooked
Prediabetes has almost no distinctive symptoms. However, there are several signs that are often associated with this condition:
- Fatigue after eating carbohydrates — heavy drowsiness or sluggishness after eating rice or bread, a sign that glucose isn't entering the cells efficiently
- Dark patches in skin folds (Acanthosis Nigricans) — velvety brownish patches on the back of the neck, armpits, or groin; a classic sign of hyperinsulinaemia
- A protruding belly even if not particularly overweight — visceral fat is both a manifestation and a cause of insulin resistance
- Feeling hungry again soon after eating — because glucose isn't entering the cells, the brain keeps sending hunger signals
- Blood pressure tending high, elevated cholesterol and triglycerides — all three often go hand in hand with insulin resistance
- PCOS in women — insulin resistance is the main cause of Polycystic Ovary Syndrome
Diagnostic Criteria: When Is It Called Prediabetes?
| Test | Normal | Prediabetes | Diabetes |
|---|---|---|---|
| Fasting Blood Glucose (FBG) | <100 mg/dL | 100–125 mg/dL | ≥126 mg/dL |
| HbA1c | <5.7% | 5.7–6.4% | ≥6.5% |
| 2-hour OGTT | <140 mg/dL | 140–199 mg/dL | ≥200 mg/dL |
Worth noting: HbA1c is the most informative test because it reflects average glucose levels over the past 2–3 months, not just the condition at that moment.
Who Needs Screening Now?
I recommend routine screening for anyone with one or more of the following risk factors:
- Age ≥35 (or younger with risk factors)
- Body Mass Index (BMI) ≥23 kg/m² (Asian threshold)
- A parent or sibling with type 2 diabetes
- History of gestational diabetes or delivering a baby >4 kg
- Hypertension, high cholesterol, or coronary heart disease
- A sedentary lifestyle and a diet high in refined carbohydrates
The Good News: Prediabetes Can Be Reversed
Unlike type 2 diabetes, which is chronic and progressive, prediabetes is fully reversible with the right intervention:
- Losing 5–10% of body weight has been proven to significantly improve insulin sensitivity
- 150 minutes of physical activity per week (even brisk walking is enough) — active muscles take up glucose without needing insulin
- A low glycaemic index diet — it's not that you "can't eat rice," but about choosing types of carbohydrates that are absorbed more slowly
- Metformin in high-risk cases — a safe, inexpensive medication proven to prevent or delay progression to type 2 diabetes
"I always tell my patients: prediabetes is not a threat, prediabetes is an opportunity. An opportunity to change course before the door truly closes."
— dr. Sebastianus Jobul, Sp.PD-KEMD, FINASIM
If you have any of the risk factors mentioned above, don't wait for symptoms to appear. Get screened now — a single simple HbA1c test can provide information that changes your life.