Your ideal blood sugar (glucose) levels depend on whether you have diabetes and the timing of the measurement (fasting, before meals, or after meals). Here are general guidelines for healthy blood sugar levels:

• For people without diabetes:
  • Fasting blood sugar (after at least 8 hours without eating): less than 100 mg/dL (5.6 mmol/L) is normal.
  • Blood sugar between 100 and 125 mg/dL (5.6 to 6.9 mmol/L) indicates prediabetes.
  • Blood sugar of 126 mg/dL (7.0 mmol/L) or higher on two separate tests indicates diabetes.
  • After meals, blood sugar typically should be below 140 mg/dL (7.8 mmol/L) within 2 hours

• For people with diabetes:
  • Before meals (preprandial): 4 to 7 mmol/L (72 to 126 mg/dL) depending on type 1 or type 2 diabetes.
  • After meals (postprandial, about 90 minutes after eating): under 9 mmol/L (162 mg/dL) for type 1 diabetes and under 8.5 mmol/L (153 mg/dL) for type 2 diabetes

* The American Diabetes Association recommends a target of 80 to 130 mg/dL before meals and less than 180 mg/dL within 2 hours after eating for people with diabetes

• Low blood sugar (hypoglycemia):
  • Blood sugar below 70 mg/dL (3.9 mmol/L) is generally considered too low for most adults with diabetes and may require treatment

These ranges serve as general guidelines; individual targets may vary based on personal health conditions, age, pregnancy, and other factors. It's best to consult your healthcare provider to determine your specific target blood sugar levels

. In summary, for a healthy adult without diabetes, aim for fasting blood sugar below 100 mg/dL and under 140 mg/dL after meals. For those with diabetes, targets are personalized but generally fall within the ranges above to reduce the risk of complications