Many people ask me, “Which test should I do to check for diabetes?” and then get confused by the long names. Let me make it easy. There are only four tests you need to know.
1. Fasting plasma glucose
This is the sugar level after at least 8 hours without food. You can drink plain water. A value of 126 mg/dL or more points to diabetes. A value from 100 to 125 means prediabetes.
2. Post-meal or glucose tolerance test (OGTT)
For this test, you drink a sweet glucose drink (75 grams) and the blood is checked two hours later. A value of 200 mg/dL or more points to diabetes. A value from 140 to 199 means prediabetes. This test is useful when other tests are borderline.
3. HbA1c
This shows your average sugar of the last 2 to 3 months. A value of 6.5 percent or more points to diabetes, and 5.7 to 6.4 percent means prediabetes. You do not need to fast for it.
4. Random sugar
A sugar of 200 mg/dL or more at any time of the day, along with symptoms like heavy thirst and frequent urine, points to diabetes.
Important rules
- Unless you have clear symptoms, doctors usually repeat the test on another day to confirm.
- Do not skip your normal food the previous evening. Eat as usual, then fast overnight.
- Tell your doctor if you have anaemia or recent blood loss, because HbA1c can be misleading in such cases.
- Medicines such as steroids can push sugar up. Share your medicine list with your doctor.
After the diagnosis
A diagnosis is not the end. It is the beginning of a plan. Along with sugar, we also check cholesterol, kidney tests, urine protein, blood pressure, eyes and feet, so that nothing is missed.
If you live in Gopanpally, Gowlidoddi, Nallagandla or Tellapur, or work in the Financial District or Nanakramguda, a simple blood sugar check is available at our clinic in Gopanpally, Gachibowli. You can read more about our diabetes care or contact us to book a visit.
Keep reading
Your family doctor,
Akhila Reddy
MBBS, DNB (Family Medicine) | TSMC Reg. No. APMC/FMR/74261
AMC Hospital, Gopanpally, Gachibowli, Hyderabad
This article is for general health education and does not replace a check-up. Every person is different, so please speak to your doctor before changing any medicine. In an emergency, call 108 or go to the nearest hospital.
References
- American Diabetes Association. Diagnosis and Classification of Diabetes: Standards of Care in Diabetes-2025. Diabetes Care 2025;48(Suppl 1). https://diabetesjournals.org/care/issue/48/Supplement_1
- World Health Organization. Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia. 2006.
- World Health Organization. Diabetes fact sheet. https://www.who.int/news-room/fact-sheets/detail/diabetes