Your body uses sugar to make energy and you get a steady supply from your diet. Your body also stores sugar for use when your blood levels are low. In normal, healthy individuals, the body regulates blood sugar levels with two chemicals released from the pancreas. Insulin helps the cells use the blood sugar for energy and glucagon helps the body tap into the sugar stored in your liver. Normal blood sugar levels vary depending on the time of day and whether or not you have eaten.
Normal Fasting Blood Sugar
Fasting blood sugar is the amount of sugar in your blood after at least eight hours of not eating. Normal fasting blood sugar levels should be below 110mg/dl. In some individuals the normal fasting level could be as low as 70mg/dl. The range of normal fasting blood sugar levels depends on several factors such as your levels before the fast. If your pancreas triggers your liver to release its sugar stores, that can also affect your levels.
Normal Post-Meal Blood Sugar
After a meal, your blood sugar levels will be significantly higher than the fasting level. The upper limit of normal blood sugar is 200mg/dl. In some individuals, post-meal blood sugar levels could be as high as the upper limit depending on what was eaten and how soon you test your blood after eating. Your blood sugar levels decline as your body uses the sugar. Normal levels should be between 70 and 140mg/dl.
Early Morning and Evening Blood Sugar
In normal individuals, blood sugar readings should be lowest in the early morning, depending on how much time has passed since your last meal. For example, if you have a snack at 2:00 a.m. and you read at 8:00 a.m., your morning blood sugar levels could be as high as 140mg/dl. Conversely, if your last meal was at 6:00 p.m., your reading may be as low as 70mg/dl. Evening readings should be higher than early morning, but the levels will vary depending on the timing of the evening meal. Those with nocturnal schedules may have higher readings in the morning and lower readings in the evening.
Conclusion
The normal blood sugar range is between 70 and 140mg/dl but different factors can influence your individual range. If your readings are consistently low, even after eating, or consistently high, consult your physician. Readings that are consistently outside the normal range may indicate a disease or disorder, such as diabetes or a hormonal condition.
References
- Virginia Mason Medical Center: What are Normal Blood Glucose Levels?
- National Diabetes Information Clearing House; Hypoglycemia; October 2008
- "Principles of Anatomy and Physiology"; Gerard J. Tortora et al.; 2010
