Dr. Prabhat AryaMD · Internal Medicine
ConditionsKnow your condition

Your sugar report, value by value.

A sugar report tells you one of three things: normal, prediabetes, or diabetes. A single high reading is not a diagnosis, but it is worth acting on, because prediabetes can usually be turned back.

Reviewed by Dr. Prabhat Arya, MBBS, MD (Internal Medicine)

Reviewed · Next review · Sources: American Diabetes Association, MedlinePlus, Testing.com, NHS

Send your report for ₹199See every value

Read this first.

Go by the range printed on your own report. The ranges below are typical adult ranges for blood taken from a vein and tested in a lab (“plasma glucose”). A finger-prick meter at home is useful for day-to-day checks, but diabetes is diagnosed on lab tests.

Diabetes is not diagnosed on one reading unless it is very high with symptoms. Usually a second test on another day, or two different tests (such as fasting sugar and HbA1c) that agree, are needed.

The most useful line is HbA1c: it shows your average sugar over the last two to three months, so one sweet meal or a bad night does not change it much. Fasting and PP sugar show what is happening today.

Readings in the prediabetes range are very common in India, even in slim people. They are a warning, not a disease, and losing a little weight, walking daily and cutting sugar, sweet drinks and refined flour can bring them back to normal. Compare with your last report to see which way they are moving.

Every value, one by one.

Fasting blood sugar (FBS)

Glucose in the blood after at least 8 hours without food (water is fine)

Typical adult range 70–99 mg/dL. 100–125 is prediabetes (impaired fasting glucose); 126 or more, on two tests, is diabetes

High usually means
Prediabetes or diabetes, most often. It can also be raised for a day or two by an infection, fever, stress, poor sleep, or steroid tablets or injections, and by not truly fasting (tea with sugar, a biscuit).
Low usually means
Below 70 mg/dL. In people on diabetes tablets or insulin, it means the medicine is too strong for the food eaten. In people without diabetes, a reading in the 60s with no symptoms is often because the blood sample stood too long before testing, which lowers the sugar; a repeat is usually normal.
Usually nothing to worry about when
It is 100–110 once, with a normal HbA1c: recheck at your next yearly test and keep active.
See a doctor when
Within a few weeks if it is 100–125 on two tests, to plan how to stop diabetes developing. Within a week if it is 126 or more. Within a day or two if it is above 250, if it is below 70 with symptoms in someone without diabetes, or if it is below 70 more than once in someone on diabetes tablets or insulin.

Post-meal sugar (PP / PPBS)

Postprandial blood sugar: glucose about 2 hours after the start of a meal

Typical adult range Below 140 mg/dL. 140–199 suggests prediabetes; 200 or more suggests diabetes

High usually means
The body is struggling to handle the sugar from a meal: often the earliest sign of prediabetes or diabetes in Indians. A very heavy, sweet or rice-rich meal, or timing the test early (1 hour instead of 2), also gives a higher reading.
Low usually means
Below about 70 mg/dL two to three hours after food, with sweating or shakiness, can be “reactive” low sugar. In people without diabetes it is usually harmless; in people on diabetes medicines it means the dose needs a look.
Usually nothing to worry about when
It is 140–160 once after a heavy meal, and the fasting sugar and HbA1c are normal.
See a doctor when
Within a few weeks if it is 140–199 on two tests. Within a week if it is 200 or more. A PP test after a normal meal is a guide; the formal glucose tolerance test (75 g glucose drink) or HbA1c is used to confirm.

Random blood sugar (RBS)

Glucose measured at any time, whatever you last ate

Typical adult range Usually below 140 mg/dL; there is no exact range because it depends on the last meal

High usually means
If 200 or more with thirst, passing a lot of urine, weight loss or blurred vision, that is diabetes. Without symptoms, a high random sugar needs a fasting sugar or HbA1c to confirm.
Low usually means
Below 70 mg/dL with sweating, shakiness, hunger or confusion is low sugar and should be treated with something sweet straight away.
Usually nothing to worry about when
It is 140–180 soon after a meal with no symptoms, and a fasting sugar or HbA1c is normal.
See a doctor when
Within a week if it is 200 or more. Within a day or two if it is above 300.

HbA1c (glycated haemoglobin)

The share of your haemoglobin with sugar stuck to it: your average sugar over the last 2–3 months

Typical adult range Below 5.7%. 5.7–6.4% is prediabetes; 6.5% or more is diabetes. For people with diabetes, below 7% is a common target, but your doctor may set a different one

High usually means
Your average sugar has been high for weeks to months: prediabetes or diabetes. Iron deficiency anaemia, very common in Indian women, can push HbA1c up a little without a real rise in sugar. Kidney failure can also make it read wrongly.
Low usually means
Below about 4% is uncommon. It can read falsely low after recent blood loss, a blood transfusion, in pregnancy, or when red cells break down early. Some inherited haemoglobin types, such as thalassaemia trait, can make HbA1c unreliable in either direction.
Usually nothing to worry about when
It is 5.7–5.9% and stable over the years: this is early prediabetes and food, activity and weight usually keep it there or bring it down.
See a doctor when
Within a few weeks if it is 6.0–6.4%. Within a week if it is 6.5% or more for the first time. If you already have diabetes, at your next visit if it is above your target, sooner if it is above 9%. If HbA1c and your fasting sugar disagree, or you are anaemic, ask for the HbA1c to be read alongside the other tests.

Estimated average glucose (eAG)

Your HbA1c converted into mg/dL, the unit your meter uses

Typical adult range Below about 117 mg/dL (matches an HbA1c below 5.7%). HbA1c 6% is about 126 mg/dL; 7% about 154; 8% about 183

High usually means
Always moves with HbA1c, because the lab works it out from HbA1c with a fixed formula. It adds no new information; it just makes HbA1c easier to compare with meter readings.
Usually nothing to worry about when
Treat it exactly as you would the HbA1c beside it.
See a doctor when
Go by the HbA1c line.

Fasting insulin (where tested)

The hormone that moves sugar from the blood into the cells, measured after an overnight fast. Sometimes printed with “HOMA-IR”, a score worked out from insulin and fasting sugar

Typical adult range Varies a lot between labs: go by the range on your report

High usually means
Usually insulin resistance: the body’s cells respond poorly to insulin, so the pancreas makes more to keep the sugar normal. It goes with a big waist, fatty liver, PCOS and prediabetes, and can show up years before the sugar rises. It does not diagnose diabetes on its own.
Low usually means
With a normal sugar, usually not a concern. With a high sugar, a low insulin can mean the pancreas is not making enough, as in type 1 diabetes or a slower adult form of it; that needs a doctor.
Usually nothing to worry about when
It is mildly high, your sugar and HbA1c are normal, and you are working on weight and activity. Many doctors do not order this test routinely, and a result does not change the advice much.
See a doctor when
Within a week if insulin is low and sugar is high, especially if you are young, slim or losing weight. If you inject insulin, this test cannot be read in the usual way.

Results that go together.

PatternsTypical, not certain
When you seeIt usually means
Fasting 100–125 and HbA1c 5.7–6.4%Prediabetes. Very common, and can usually be turned back with weight loss of 5–7%, 30 minutes of walking most days and less sugar and maida. Recheck in a year, or sooner with symptoms. See prediabetes.
Normal fasting sugar, high PP sugarOften the earliest sign in Indians that the body is handling meals poorly. An HbA1c or a formal glucose tolerance test settles whether it is prediabetes or diabetes.
High HbA1c, normal fasting and PP sugar, with low haemoglobinIron deficiency anaemia can push HbA1c up. Treat the anaemia and repeat; the fasting sugar may be the better guide meanwhile. See the blood count guide.
High sugar with high triglycerides, low HDL and raised SGPTInsulin resistance with fatty liver: the commonest combination on Indian health checks. All of these improve together with weight loss. See the lipid profile and fatty liver.
High sugar with weight loss, thirst and passing a lot of urineDiabetes that is not controlled. See a doctor within a day or two, sooner if there is vomiting or drowsiness.

Get help today if

  • Sugar above 250–300 mg/dL with vomiting, tummy pain, deep fast breathing, a fruity smell on the breath or drowsiness: go to hospital today. This can be diabetic ketoacidosis. If you take a gliflozin tablet (dapagliflozin, empagliflozin and similar), these symptoms need hospital today even when the sugar is normal or only a little high.
  • Sugar below 70 mg/dL with confusion, fits or fainting: if the person is awake and can swallow, give sugar, glucose or a sweet drink at once, then a snack. If they cannot swallow, are having a fit or are unconscious, give nothing by mouth and call 112. Call 112 too if they are not clearly better within 15 minutes. Low sugar on insulin or on tablets such as glimepiride or gliclazide can come back over the next hours, so the person needs a doctor today.
  • Sugar above 400 mg/dL, or a meter showing “HI”, in anyone, especially an older person who is drowsy or not drinking enough: go to hospital today.

Call 112 or go to the nearest emergency department. Ambulance: 108 (102 in some states).

Read more.

Questions people ask.

  1. My fasting sugar is 110. Do I have diabetes?

    Not on this number. 100–125 mg/dL is the prediabetes range: a warning that sugar handling is starting to slip. Check HbA1c too, as it sometimes shows diabetes even when the fasting sugar is below 126, and work on weight, daily walking and less sugar and refined flour; these often bring it back to normal. Recheck in about a year.

  2. What is a normal HbA1c?

    Below 5.7%. 5.7–6.4% is prediabetes and 6.5% or more is diabetes. HbA1c can read slightly high in iron deficiency anaemia and wrongly in some blood conditions and kidney disease, so it is read together with your sugar readings.

  3. How long after a meal should PP sugar be checked?

    Two hours after you start eating. Eat your usual meal, sit quietly, and do not have anything except water until the blood is taken. A reading at one hour will be higher and cannot be compared with the usual range.

  4. Can stress or a fever raise my sugar?

    Yes. Infections, fever, injury, poor sleep, strong stress and steroid medicines can push sugar up for a while. A single high reading during an illness should be repeated once you are well, along with an HbA1c.

Where this can be checked

These are trusted general sources. The advice on this page is Dr. Arya’s, written for patients in India. Ranges differ between labs: go by the range printed on your own report.

Your whole report, read by your doctor.

Send every page, old reports too. He reads them himself and tells you what changed and what to do.

Send your report for ₹199

Dr. Prabhat Arya · MBBS, MD (Internal Medicine)