A non-fasting glucose test measures the amount of glucose (sugar) in your blood after eating. Normal non-fasting (A1C) levels are below 140 milligrams per deciliters of blood (mg/dL). If between 140 and 199 mg/dL, you may have prediabetes. If above 200 mg/dL, you may have diabetes.
This article explains the purpose of a non-fasting glucose test and how it differs from a fasting glucose test. It also describes what a normal result is for each test and at what point a person may need medical assistance for hypoglycemia (low blood glucose) or hyperglycemia (high blood glucose).
Verywell / Theresa Chiechi
Why Non-Fasting Glucose Is Tested
Fasting blood glucose and non-fasting blood glucose are two measures that are helpful in the diagnosis of prediabetes and diabetes. Non-fasting blood glucose offers an additional benefit in that it can also help inform diabetes management.
The fasting glucose test only measures your blood glucose at a specific point: after you haven't consumed anything for eight hours. It tells you how low you can expect your blood glucose to go.
In contrast, the non-fasting A1C helps determine your average blood sugar level over a period of two to three months. This tells you about how well your blood glucose is being kept in check and is more informative than the blood tests used to monitor blood sugar at home.
What Is Blood Glucose?
Blood glucose is the body's main energy source. Food you eat gets broken down into sugar and sent to the blood. Insulin then helps that sugar go into your cells, where it is used as "fuel" or stored away.
Non-Fasting Glucose Levels: Normal, Elevated, and High
The following non-fasting glucose levels indicate whether an adult is prediabetic, diabetic, or neither:
- Normal: Under 140 mg/dL
- Prediabetes: 140 and 199 mg/dL
- Diabetes: Above 200 mg/dL
As a point of comparison, here are the fasting blood sugar levels used to help with diagnosis:
- Normal: Less than 100 mg/dL
- Prediabetes: 100 mg/dL to 125 mg/dL
- Diabetes: 126 mg/dL or higher
Levels in People With Diabetes
Measuring glucose levels after meals is important not just for diagnosis, but in the treatment of diabetes too. Results obtained during home testing can reveal whether you need an insulin shot to move excess sugar out of your blood and into cells.
Non-fasting sugar levels among adults with type 1 diabetes should be:
- Before meals: From 90 to 130 mg/dL
- After meals (1 to 2 hours after eating): Less than 180 mg/dL
- At bedtime: From 90 to 150 mg/dL
Non-fasting glucose levels among adults with type 2 diabetes should be:
- Before meals: From 70 to 130 mg/dL
- After meals (1 to 2 hours after eating): Less than 180 mg/dL
- At bedtime: From 90 to 150 mg/dL
It is possible to get a falsely high A1C result. This is most likely to happen in someone with low iron levels, kidney failure, or liver disease. Certain medications or vitamin supplements like vitamin E can also increase your A1C levels. Stress and poor sleep habits can also play a role in elevated A1C levels.
Guidelines for Blood Glucose Monitoring
Risks of Low Non-Fasting Blood Glucose
Hypoglycemia is a glucose level below 70 mg/dL. If the body doesn’t have enough glucose, this can lead to symptoms such as:
- Difficulty speaking
- Dizziness
- Fast breathing
- Feeling anxious or weak
- Hunger
- Nausea
- Shakiness
If a person has diabetes, hypoglycemia can sometimes be a side effect of diabetes medication. If a person has hypoglycemia and the glucose is too low, it could result in a diabetic coma. If the person is unconscious, it is vital to call 911 immediately.
Anyone with diabetes should keep the contact information of their healthcare provider nearby so they can reach out for help when needed.
When to Seek Emergency Help
Call 911 if your blood sugar falls below 70 mg/dL or if you feel tired or dizzy.
Risks of High Non-Fasting Glucose Levels
Hyperglycemia is high blood sugar. This happens when the body doesn’t have enough insulin and there is too much sugar in the blood. Symptoms of hyperglycemia include:
- Blurred vision
- Fatigue
- Frequent urination
- Headache
- Increased hunger and/or thirst
If hyperglycemia is not treated properly, you risk both short- and long-term health issues, such as kidney problems. And if your blood sugar climbs too high and is left untreated, you risk lapsing into a diabetic coma.
Hyperglycemia can be maintained and/or prevented by:
- Avoiding smoking and alcohol
- Eating right
- Exercising
- Maintaining a healthy weight
- Taking medication as prescribed
It's important to work with your healthcare provider to get the best outcome regarding this condition.
Symptoms of Hyperglycemia
Ketoacidosis
Diabetic ketoacidosis (DKA) can develop in people who have type 1 diabetes and untreated hyperglycemia. This is when toxic acids or ketones build up in the blood. This is an extremely serious condition that can cause coma or death.
What Is Diabetic Ketoacidosis (DKA)?
Summary
Diabetes is a serious condition that requires diabetics to remain proactive about their blood glucose (blood sugar) levels. If they don't, they could develop hypoglycemia (low blood sugar), hyperglycemia (high blood sugar), or ketoacidosis (a serious complication of diabetes). Maintaining a healthy diet and exercising regularly can help keep blood sugar levels under control.
A Word From Verywell
Diabetes can create a lot of health complications if it's not managed properly. Checking blood sugar on a regular basis is essential. For many people, it also represents one of the biggest adjustments they have to make to a diabetic lifestyle. But if diabetes goes untreated, it can result in dangerous consequences.
Frequently Asked Questions
What are normal blood sugar levels in someone without diabetes?
A random blood sugar taken at any time during the day in people without diabetes should be below 200 mg/dL. A study found that blood sugar levels in these individuals stays between 70 mg/dL and 130 mg/dL at least 96% of the time.
What are normal non-fasting glucose levels in pregnancy?
A non-fasting glucose test is used to rule out gestational diabetes in someone who is pregnant. For most people, a blood sugar level less than or equal to 140 mg/dL is considered normal.
What can cause false high blood sugar readings?
Blood glucose testing is usually very reliable, but it is possible to get an inaccurate result. Extreme temperatures or humidity, incorrect use of test equipment, test strips that aren't stored correctly, and the use of certain medications can cause this.
Is there anything you shouldn't eat before taking a non-fasting A1C test?
It doesn't matter what you eat the day of the test, but what you eat over time can affect your results. In general, eat healthy fats, protein, and whole grains, and avoids sugar and refined carbohydrates.
What is good blood sugar 2 hours after eating?
A blood sugar target is the range you try to reach as much as possible. These are typical targets: Before a meal: 80 to 130 mg/dL. Two hours after the start of a meal: Less than 180 mg/dL.Is 117 blood sugar normal 2 hours after eating?
In general: Less than 140 mg/dL (7.8 mmol/L ) is normal. 140 to 199 mg/dL (7.8 to 11.0 mmol/L ) is consistent with prediabetes. 200 mg/dL (11.1 mmol/L ) or higher after two hours suggests diabetes.Is 115 a good blood sugar level after eating?
Based on the data of healthy individuals wearing CGM, it appears that it is safe and healthy to strive for a fasting glucose between 72-85 mg/dL, a post-meal glucose level of 110 mg/dL or lower, and an average glucose of 100 mg/dL or lower.What should your blood sugar be 2 hours after eating for non diabetics?
What Are Normal Blood Glucose Levels for People Without Diabetes? Normal blood glucose ranges for people without diabetes are: Fasting: 70-99 mg/dL. 1-2 hours after a meal: less than 140 mg/dL.