About 12 to 24 hours after taking a high carbohydrate meal.

About 12 to 24 hours after the last meal, a person's blood sugar level normally varies from 60 to 90 mg per 100 ml of blood, although it may rise to 130 mg per 100 ml after meals high in carbohydrates. That the blood sugar level is maintained within a fairly narrow range, despite uneven intake of sugar, is due to the bodily process called Homeostasis.

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