Hello, it may sound strange but this disorder may indicate inadequate blood sugar control but not as serious as diabetes (prediabetes which means before diabetes ). The high fasting blood sugar is indicative. Individuals with this disorder fail to secrete insulin on time but they still have the potential to secrete the required amount, they just do so late enough to cause hypoglycemia 2-3 hours after the meal. In normal individuals insulin is secreted on time, therefore it won t let the blood sugar get too high after the meal. When insulin secretion is inadequate or delayed the blood sugar rises fast and may trigger an even more exaggerated insulin secretion but not on the right time. A 3-hour oral glucose tolerance test may help to reveal this disorder, particularly if insulin levels are measured as well. This disorder is supposed to be more exaggerated when eating food with high carbohydrate content or high glycemic index. Oatmeal is not a low-carbohydrate meal (it s not the worst for blood sugar either) so this may well be the cause of your hypoglycemia. Perhaps you will experience the same problem with other high carbohydrate food like sweets, fruits with high carbohydrate content (bananas for example), etc. I hope you find my comments helpful! Be sure to discuss this with your doctor as other causes are also possible (but less likely) and investigation might be required. Kind Regards!