TempoLife › Features › Blood sugar explained › after-eating-1h
One hour after eating — reference ranges
The usual moment of the peak: glucose tops out roughly 45-75 minutes after a meal, then falls. There is no universal diagnostic threshold at one hour.
| Band | mmol/L | mg/dL | What it means |
|---|---|---|---|
| Typical peak | under 7.8 | under 140 | In most people without diabetes, glucose stays below 7.8 mmol/L even at the peak. |
| Higher peaks | 7.8-11.0 | 140-199 | Common after very large or sugary meals; repeatedly high one-hour values with a slow fall are a pattern worth checking. |
| Very high peaks | above 11.1 | above 200 | A single random value of 11.1 mmol/L or higher with symptoms of diabetes is itself a diagnostic finding. |
Reading it in context
One hour is a trend number, not a diagnosis: meal size, meal composition, exercise before eating and the speed of eating all move it, and the official criteria use fasting, two-hour and HbA1c values instead. What matters at one hour is the shape — how high it goes and how fast it comes back.
Meals that spike high at one hour and crash at two-to-three (the "roller coaster") are the pattern people notice as energy slumps, cravings and early hunger. Protein, fibre and fat in the meal flatten the same curve without changing the total calories.
When to see a clinician
- Values repeatedly above 11.1 mmol/L after ordinary meals — see a clinician.
- Spikes followed by hypo-like symptoms (sweating, shaking, sudden hunger) — the pair is worth investigating.
Reference only, not a diagnosis. The thresholds on this page are population-level WHO and ADA values; your clinician interprets your own numbers against your history, medicines and other tests. If a value comes with symptoms, or keeps moving in the wrong direction, that is the signal to act on — not this page.