A blood sugar level of 7.8 mmol/L (140 mg/dL) is considered the upper limit of normal when measured two hours after eating. Whether it's considered "high" depends on the context of when it was measured.
Here's a breakdown:
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Fasting Blood Sugar (After not eating for at least 8 hours): A fasting blood sugar level of 7.8 mmol/L (140 mg/dL) would be considered very high and indicative of diabetes. Normal fasting blood sugar is generally below 5.6 mmol/L (100 mg/dL).
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Two Hours After Eating (Postprandial): A blood sugar level of less than 7.8 mmol/L (140 mg/dL) is generally considered normal two hours after eating. A level between 7.8 mmol/L (140 mg/dL) and 11.0 mmol/L (199 mg/dL) suggests prediabetes (impaired glucose tolerance). A level of 11.1 mmol/L (200 mg/dL) or higher indicates diabetes. Therefore, 7.8 mmol/L right at the two-hour mark would be borderline and should be discussed with a healthcare professional.
To summarize:
| Measurement Time | mmol/L | mg/dL | Interpretation |
|---|---|---|---|
| Fasting (8+ hours without eating) | < 5.6 | < 100 | Normal |
| Fasting | ≥ 7.0 | ≥ 126 | Diabetes |
| 2 Hours After Eating | < 7.8 | < 140 | Normal |
| 2 Hours After Eating | 7.8-11.0 | 140-199 | Prediabetes (Impaired Glucose Tolerance) - 7.8 is the lower boundary |
| 2 Hours After Eating | ≥ 11.1 | ≥ 200 | Diabetes |
If you're concerned about your blood sugar levels, it's always best to consult with a doctor or other qualified healthcare professional. They can perform the necessary tests and provide personalized advice based on your individual circumstances.
