Brief Answer: Various causes.Lab error, reagent change, diet etc Detailed Answer: Hello, I have gone through your query and understand your concern. There are various causes for changing of fasting blood sugars. 1. Error in laboratory. 2. Use of different reagents 3. Further change in diet 4. Physical activity You have to understand that amount of glucose in your blood changes throughout the day depending on what you're eating and drinking. Thus if you checked your glucose too earlier or too late after fasting ( usually recommended fasting is 8 hours) can change the fasting values of blood sugar. As your 8 of the fasting readings are normal, you may not be in prediabetic stage. It may be due to any one of the factor which i mentioned above for change in your blood sugar. Thus nothing to be concerned too much about this. Exercise regularly for 45 minutes a day for at least 5 days a week. Eat plenty of vegetables and fruits. Avoid deep fried and fat rich foods. Drink plenty of water. Hope this helps. Please write back for further queries. Wishing you good health.

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