Gly LogBlood sugar after eating: ranges and timing
After-meal (postprandial) blood sugar shows how much your blood sugar rises after you eat. It changes a lot with what and how much you eat, which is exactly why it is worth logging.
2-hour ranges
| Situation | Range (mg/dL) |
|---|---|
| Oral glucose tolerance test, 2-hour value — normal | Under 140 |
| Oral glucose tolerance test, 2-hour value — prediabetes | 140 – 199 |
| Oral glucose tolerance test, 2-hour value — diabetes threshold | 200 or higher |
| Common target for adults with diabetes (1–2 hours after a meal) | Under 180 |
The 140 and 200 values come from the oral glucose tolerance test, where you drink 75 g of glucose at a clinic. Readings after a normal meal at home vary with the food, so they can't be compared to these values one-to-one.
Start the clock when you start eating
The 1-hour and 2-hour marks are usually counted from your first bite, not from when you finish. If a meal takes a while, counting from the end means checking later than intended.
1 hour or 2 hours?
- 2 hours — the most widely used time point. It shows whether your blood sugar is coming back down.
- 1 hour — closer to the peak. Some people, such as those managing gestational diabetes, are told to use the 1-hour value.
Use whichever your care team recommends, and once you pick one, stick with it so your readings stay comparable.
This article is general health information and does not replace diagnosis or treatment. Targets and how often to check differ from person to person, so follow your care team first. If you have symptoms of low blood sugar or readings far outside your range, contact your care team right away.
Reference: American Diabetes Association (ADA) Standards of Care
Last updated 2026-10-26