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What is Normal, Low or High, & More

When people are newly diagnosed with diabetes, one of the first questions they ask is what their blood sugar levels should be; what is normal, too high, or too low? Since everyone’s personal health history and the way their body functions is as unique as a fingerprint, it may affect how the body responds to food, medication, and other factors that influence blood sugar levels.

Health organizations provide guidelines for normal glucose levels in people without diabetes, which are slightly different from the normal or target levels recommended for people diagnosed with diabetes. If you have diabetes, your healthcare provider will work with you to personalize your target blood sugar levels to meet your individual health needs.

This article is intended to help you get started with understanding the basic aspects of blood sugar levels, including:

What is blood sugar?

When you eat, the carbohydrate in your food is broken down into a usable form of energy called glucose. Glucose — also known as sugar — enters the bloodstream and a hormone called insulin helps move it into our cells.

This process lowers the amount of glucose in the bloodstream. When this process works efficiently, your muscles and organs have the fuel they need without there being too much glucose remaining in the blood.

What are normal blood sugar levels?

Health organizations like the American Diabetes Association (ADA) and Centers for Disease Control and Prevention (CDC) provide the following guidelines on normal blood sugar levels for people without diabetes:

Fasting plasma glucose

This blood sugar measurement is taken while you’re fasting – at least 8 hours from when you last ate – such as first thing in the morning.

  • ADA recommendation: Fasting plasma glucose level below 100 mg/dL.

After meal / 2 hour plasma glucose

This blood sugar measurement is taken 2 hours after the start of a meal, or 2 hours after ingesting a sugary liquid during an oral glucose tolerance test.

  • ADA recommendation: Blood glucose level below 140 mg/dL.


This blood test is taken independent of when you have eaten. It measures the amount of glucose that is stuck to the hemoglobin (part of your red blood cells), which accumulates over approximately 3 months.

  • CDC recommendation: Less than 5.7%.

Normal blood sugar levels chart


Fasting plasma glucose2 hours after a mealA1C
Below 100 mg/dLBelow 140 mg/dLLess than 5.7%


Target blood sugar levels for people with diabetes

People with diabetes have difficulty creating or using enough insulin, which is the hormone that helps convert glucose into energy. Although there is no universal blood sugar chart for everyone with diabetes, clinical organizations like the ADA and American Association of Clinical Endocrinologists (AACE) offer guidelines on target blood sugar levels as a starting point.

Healthcare providers typically tailor normal blood sugar target ranges to an individual diabetes care plan. This includes considering your:

  • Age
  • Lifestyle
  • Years since diabetes diagnosis
  • Other health conditions
  • Risk for severe low blood sugars
  • Mental state
  • Economic resources available to reach blood sugar goals

If you do not have target guidelines from your healthcare provider yet, you can use the blood sugar level charts below. This will help you get started with testing at home with a blood glucose meter and will make it easier to understand target A1C levels.

Target blood sugar ranges for non-pregnant people with diabetes

Before Meals70-130mg/dLLess than 110 mg/dL
2 Hours After a MealLess than 180 mg/dLLess than 140 mg/dL
A1C (HbA1c)Less than 7. 0%Less than 6.5%


Target blood sugar ranges for pregnant people with diabetes

Blood sugar targets during pregnancy are lower due to hormonal influences. The ADA, AACE, and Joslin Diabetes Center have slightly different guidelines for target blood sugar levels during pregnancy. In general, pregnant women with diabetes will want to follow individual guidelines provided by their endocrinologist.

The ADA recommends maintaining blood sugar levels of 95-140 mg/dL for pregnant women. However, some providers recommend an even tighter goal of blood glucose levels below 89 mg/dL before a meal and below 120 mg/dL after a meal.

To keep close tabs on levels, most diabetes specialists recommend that women with diabetes during pregnancy check their blood sugar:

  • First thing in the morning (fasting)
  • Before all meals
  • 1 hour after all meals
  • At bedtime
  • Occasionally at 3 a.m.

Track your own personal ranges with our free weekly and monthly blood sugar charts >

Factors that can affect blood sugar levels

If you have prediabetes or diabetes, you may have insulin resistance or an inability to produce insulin. This means your body has difficulty regulating blood sugar levels on its own.

It’s a delicate balance to maintain, so the following list can help you familiarize yourself with factors that can cause your blood glucose levels to go up or down.

Why your blood sugar level may be high

Based on the ADA guidelines above, if your blood sugar is above 180 mg/dL two hours after a meal, it is considered above the normal range. What might cause your glucose or blood sugar to rise? Consider the following factors:

  • Consuming more carbohydrates or a larger meal than usual
  • Not taking enough insulin or oral diabetes medication based on carbohydrates or activity levels
  • Reduced physical activity
  • Illness, stress, and pain (both short-term and long-term)
  • Menstrual periods
  • Dehydration
  • Side effects from medications like steroids or antipsychotics

Why your blood sugar level may be low

If blood sugar drops below 70 mg/dL, it is below normal levels. This can be caused by a variety of factors, such as:

  • Not eating enough or missing a meal or snack
  • Reducing the amount of carbohydrates you normally eat
  • Alcohol consumption — especially if you’re drinking on an empty stomach
  • Taking too much insulin or oral diabetes medication based on carbohydrates or activity levels
  • Increased physical activity
  • Side effects from medications (other than steroids or antipsychotics)

If you have diabetes, keep your blood glucose meter and sources of fast-acting glucose (like glucose tabs or fruit juice) close by in case your blood sugar drops. This is especially important for people with hypoglycemia unawareness, which is a condition that causes symptoms of low blood sugar to go unnoticed.

Eating balanced meals and snacks at regular times throughout the day is a big part of maintaining normal blood glucose levels. Check out our article on meal planning for diabetes to better understand the three macronutrients where calories come from and which have the biggest effect on blood sugar.

Meal Planning for Diabetes: How to Optimize Your Diet [Free Meal Plan Chart] >

Everyone will respond differently to certain factors, which is why it’s important to have individualized target glucose levels. To help you reach your target blood glucose goals, work with your healthcare provider to discuss modifications to your diet, physical activity, or medications, and alert them of other factors like a recent illness or stressful event.

High blood sugar: hidden dangers

In the short term, high blood sugar levels can zap your energy, cause excessive thirst and urination, and blur your vision. High blood sugar levels can also lead to dehydration, dry and itchy skin, and infections. Minimizing the time spent above your target blood sugar range can help you feel your best and will help prevent complications and injury to your body.

Over time, high blood sugar affects many parts of the body. Chronic high blood sugar can start to cause noticeable changes, including:

  • Memory problems
  • Vision problems like blurriness, diabetic retinopathy, and blindness
  • Gum disease that leads to tooth loss, which can make eating healthy foods difficult due to problems chewing
  • Heart attack and stroke due to increased plaque build-up in the vessels and other vascular issues
  • Kidney disease, which can lead to the need for dialysis or a kidney transplant
  • Nerve damage that can cause decreased sensation in the feet and legs which increases the risk for wounds to turn into serious infections and even amputation

Nerve damage from high blood sugar can also cause a variety of symptoms including:

  • Pain and tingling in the feet and hands
  • Difficulty emptying your bladder
  • Problems during the digestion process after eating, which can cause food to sit in the stomach too long and lead to nausea, vomiting, and erratic blood sugar levels

People with diabetes are often reluctant to talk about it, but nerve damage from high blood sugar can also affect sexual response and function for men and women. Don’t be embarrassed to reach out to your doctor for help in any of these areas.

Checking your blood sugar frequently and taking immediate action when it is above range can reduce your risk of complications.

High blood sugar chart and action plan

High blood sugar is also referred to as hyperglycemia. This happens when the body does not have enough insulin or can’t use insulin properly due to insulin resistance.

The numbers below represent values in the hyperglycemic range and require action to bring levels down to a normal range.


Blood Sugar ReadingAlert Level and Treatment Plan
180-250 mg/dLYellow Flag: Blood sugar is above normal levels.

When blood sugar levels are high, it can indicate that the body does not have enough insulin or glucose lowering medication. Levels may be elevated due to a large meal, if you have an illness or infection, are stressed, or are inactive. If you are newly diagnosed, it may take a little time to get you below this range.

Your healthcare provider may provide individualized instructions on when to contact the office. If you have two or more unexpected blood sugars over 250 mg/dL, notify your healthcare provider for instructions.

Higher than 250 mg/dLRed Flag: Blood sugar is very high and requires immediate treatment.

More than two unexpected blood sugar readings over 250 mg/dL require medical attention. Testing for ketones is recommended for people with Type 1 diabetes and those with Type 2 diabetes on insulin therapy who are having vomiting and symptoms of severe illness.

When blood sugar levels are this high, it could be a sign of ineffective glucose management, a problem with your insulin or insulin pump infusion set, illness, or another problem. Notify your healthcare provider for further treatment instructions.

Do not exercise if your blood sugar is over 250 mg/dL and make sure to drink plenty of water.

Low blood sugar: what to watch out for

Hypoglycemia (low blood sugar) can occur in people with diabetes who:

  • Take too much medication or insulin
  • Are late eating a meal or snack
  • Have increased physical activity
  • Drink too much alcohol

Symptoms of low blood sugar include feeling weak, sweaty or clammy, confused, hungry and/or irritable. Sometimes people experience a fast heartbeat and some symptoms may make a person appear to be drunk. A severely low blood sugar can result in unconsciousness, seizures, coma or death — especially when a low occurs during the night.

Low blood sugar affects many parts of the body, but the most frustrating part can be that hypoglycemia can happen anytime and anywhere — even when you think you are closely following the plan for your diabetes care. If low blood sugar is severe, people may need to go to the hospital to help raise their glucose level or miss work due to the side effects.

It can happen during a date, during a business meeting, or even while driving, which is the most dangerous scenario if there is confusion or loss of consciousness while behind the wheel. It’s important to use your blood glucose meter to check your blood sugar before you drive to keep yourself and others safe. Frequent testing with your blood sugar meter and taking action when blood sugar is trending low can prevent a severe low and keep your life on track.

Low blood sugar chart and action plan

Low blood sugar is also called hypoglycemia. The numbers below represent values in the hypoglycemic range and require action to bring blood sugar levels up into a normal range.


Blood Sugar ReadingAlert Level and Treatment Plan
50 mg/dL or underRed Flag: Blood sugar is critically low and requires immediate treatment.

If a person is unable to speak and/or is not alert, treat with glucagon via injection or nasal spray. Call emergency medical response if necessary. Do not place food or drink into the mouth.

If a person is alert and able to speak clearly, treat with 15 grams of rapid-acting carbohydrate such as glucose gel, 4 oz regular soda, or fruit juice. Re-test blood sugar in 15 minutes and repeat as needed to bring blood sugar within range.

51-70 mg/dLRed Flag: Blood sugar is below normal levels and requires immediate treatment.

Treat with 15 grams of rapid-acting carbohydrate and re-test in 15 minutes. Repeat treatment as needed to bring blood sugar within range.

71-90 mg/dLYellow Flag: Blood sugar levels should be watched and treated as needed.

If you’re having symptoms of low blood sugar, treat with 15 grams of rapid-acting carbohydrate and re-test in 15 minutes.

Repeat treatment or follow with a meal. If it is meal time, move forward with eating the meal. People often fall into this range when they are late for a meal or have been especially active.

Anytime your symptoms don’t match the number on your blood sugar meter, repeat the test. Don’t count on your body to tell you if your blood sugar is high or low — many of the symptoms of highs and lows are similar.

Discussing your unique health goals and challenges with your healthcare provider can provide customized target ranges for normal blood sugar levels and action plans based on your needs. Maintaining healthy blood sugar levels is important to your overall health, so remember to check your blood sugar frequently. Taking immediate action when blood sugar is above range can help reduce your risk of health complications, and if low, keep you safe.

Blood sugar test


A blood sugar test measures the amount of a sugar called glucose in a sample of your blood.

Glucose is a major source of energy for most cells of the body, including brain cells. Glucose is a building block for carbohydrates. Carbohydrates are found in fruit, cereal, bread, pasta, and rice. Carbohydrates are quickly turned into glucose in your body. This can raise your blood glucose level.

Hormones made in the body help control blood glucose level.

Alternative Names

Random blood sugar; Blood sugar level; Fasting blood sugar; Glucose test; Diabetic screening – blood sugar test; Diabetes – blood sugar test

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

The test may be done in the following ways:

  • After you have not eaten anything for at least 8 hours (fasting)
  • At any time of the day (random)
  • Two hours after you drink a certain amount of glucose (oral glucose tolerance test)

How the Test will Feel

adam.com”>When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.

Why the Test is Performed

Your doctor may order this test if you have signs of diabetes. More than likely, the doctor will order a fasting blood sugar test.

The blood glucose test is also used to monitor people who already have diabetes.

The test may also be done if you have:

  • An increase in how often you need to urinate
  • Recently gained a lot of weight
  • Blurred vision
  • Confusion or a change in the way you normally talk or behave
  • Fainting spells
  • Seizures (for the first time)
  • Unconsciousness or coma


This test may also be used to screen a person for diabetes.

High blood sugar and diabetes may not cause symptoms in the early stages. A fasting blood sugar test is almost always done to screen for diabetes.

If you are over age 45, you should be tested every 3 years.

If you’re overweight (body mass index, or BMI, of 25 or higher) and have any of the risk factors below, ask your health care provider about getting tested at an earlier age and more often:

  • High blood sugar level on a previous test
  • Blood pressure of 140/90 mm Hg or higher, or unhealthy cholesterol levels
  • History of heart disease
  • Member of a high-risk ethnic group (African American, Latino, Native American, Asian American, or Pacific Islander)
  • Woman who has been diagnosed with gestational diabetes
  • Polycystic ovary disease (condition in which a woman has an imbalance of female sex hormones causing cysts in the ovaries)
  • Close relative with diabetes (such as a parent, brother, or sister)
  • Not physically active

adam.com”>Children age 10 and older who are overweight and have at least two of the risk factors listed above should be tested for type 2 diabetes every 3 years, even if they have no symptoms.

Normal Results

If you had a fasting blood glucose test, a level between 70 and 100 mg/dL (3.9 and 5.6 mmol/L) is considered normal.

If you had a random blood glucose test, a normal result depends on when you last ate. Most of the time, the blood glucose level will be 125 mg/dL (6.9 mmol/L) or lower.

The examples above show the common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

If you had a fasting blood glucose test:


  • A level of 100 to 125 mg/dL (5.6 to 6.9 mmol/L) means you have impaired fasting glucose, a type of prediabetes. This increases your risk of developing type 2 diabetes.
  • A level of 126 mg/dL (7 mmol/L) or higher usually means you have diabetes.

If you had a random blood glucose test:

  • A level of 200 mg/dL (11 mmol/L) or higher often means you have diabetes.
  • Your provider will order a fasting blood glucose, A1C test, or glucose tolerance test, depending on your random blood glucose test result.
  • In someone who has diabetes, an abnormal result on the random blood glucose test may mean that the diabetes is not well controlled.

Other medical problems can also cause a higher-than-normal blood glucose level, including:

  • Overactive thyroid gland
  • Pancreatic cancer
  • Swelling and inflammation of the pancreas (pancreatitis)
  • Stress due to trauma, stroke, heart attack, or surgery
  • Rare tumors, including pheochromocytoma, acromegaly, Cushing syndrome, or glucagonoma

adam.com”>A lower-than-normal blood glucose level (hypoglycemia) may be due to:

  • Hypopituitarism (a pituitary gland disorder)
  • Underactive thyroid gland or adrenal gland
  • Tumor in the pancreas (insulinoma – very rare)
  • Too little food
  • Too much insulin or other diabetes medicines
  • Liver or kidney disease
  • Weight loss after weight loss surgery
  • Vigorous exercise

Some medicines can raise or lower your blood glucose level. Before having the test, tell your provider about all the medicines you are taking.

For some thin young women, a fasting blood sugar level below 70 mg/dL (3.9 mmol/L) may be normal.


There is little risk involved with having your blood taken.Veins and arteries vary in size from one person to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

  • Excessive bleeding
  • Fainting or feeling lightheaded
  • Multiple punctures to locate veins
  • Hematoma (blood accumulating under the skin)
  • Infection (a slight risk any time the skin is broken)


American Diabetes Association. 2. Classification and diagnosis of diabetes: standards of medical care in diabetes – 2019. Diabetes Care. 2019;42(Suppl 1):S13-S28. PMID: 30559228 www.ncbi.nlm.nih.gov/pubmed/30559228.

Chernecky CC, Berger BJ. Glucose, 2-hour postprandial – serum. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:585.

Chernecky CC, Berger BJ. Glucose tolerance test (GTT, OGTT) – blood. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:591-593.

Monitoring Blood Glucose

Blood sugar is also called blood glucose.

Why do I Need to Check My Blood Glucose?

  • To keep you safe
  • To help you and your health care team manage your blood glucose levels
  • To help you change your insulin doses
  • To help you manage your daily activities, like school, work, exercise, and the food you eat

Always Check at these Times:

  • Before breakfast, lunch, and dinner
  • Before bed
  • When you have signs of low blood glucose (see ‘Low Blood Glucose’ on page 46)
  • Each time you get in a car to drive

Sometimes You will Need to Check at these Times:

  • Middle of the night
  • Before, during, and after exercise

Check More Often:

  • When you are sick
  • Check blood glucose between 2 a. m. and 4 a.m. if there is a chance your blood glucose may be low.
  • Check for 2 to 3 nights after changing your Lantus® insulin dose.
  • When you have an unusual amount of exercise late in the day.
  • When you are sick.
  • When your blood glucose is low before bed.

What Supplies do I Need?

Blood Glucose Meter

Blood Glucose Test strips

Lancet Device


Container for used lancets (sharps container or a container made of thick plastic, like a detergent bottle or bleach bottle)

How do I Check My Blood Glucose?

  1. Wash your hands.
  2. Put the lancet in the lancet device.
  3. Put the test strip into the blood glucose meter.
  4. Stick the finger on its side near the top of the finger (Picture 1).
  5. Squeeze the finger so a drop of blood comes up on the skin.
  6. Touch the blood sample to the test strip.
  7. Read the blood glucose number on meter.


Picture 1: Poke the side of the finger with the lancet

Important Tips

  • Use a new lancet every time you check your blood glucose.
  • Throw away the lancet right after it is used. Put it in the container.
  • When the container is almost full, tape the lid on tightly.
  • Write “SHARPS” on the front, and put it in the trash.

What Number should My Blood Glucose be?

Blood glucose is measured in mg/dl. The normal range for blood glucose for people without diabetes is 70 to 120 mg/dl.

The Diabetes Center has guidelines for blood glucose readings. This is called a target range. There may be times when your healthcare provider gives you a different target range, like for bedtime, with exercise, or after eating.

Nationwide Children’s Hospital Diabetes Center Target Blood Glucose Ranges

AgeBlood Glucose mg/dl
0 to 5 years old100 to 180
6 to 9 years old80 to 140
10 years old or more70 to 120

The goal is to keep the blood glucose within the target range most of the time.

What Should I do After I Check my Blood Glucose?

Write the blood glucose number in a log book or on a log sheet (page 18), and:

  • Include all of your blood glucose numbers.
  • Write a comment if there is a reason the blood glucose is above or below target.


Important Tips

  • Take your blood glucose meter with you when you are away from home.
  • Know your blood glucose numbers when you call the clinic or the doctor.
  • Bring your blood glucose meter and blood glucose records to all your appointments.
  • Bring a list of any questions that you may have.

How do I Take Care of My Blood Glucose Meter?

  • Set the date and time when you get a new meter.
  • Make sure the date and time are right each time you use your meter.
  • Use the control solution as needed. This will let you know the meter and test strips are working right. Use it:
    • When you get a new meter.
    • When you get new test strips.
    • When you think that the meter is not giving you the right blood glucose number.
  • Keep the meter and test strips out of very hot or very cold temperatures. This can cause blood glucose numbers to be wrong.
  • Keep meter and test strips in a case, away from sunlight.
  • Keep test strips in the container they come in. Keep the lid closed.
  • Keep extra batteries with your meter.
  • There is a phone number on the back of each blood glucose meter. Call that number if your meter is not working or you have questions about how to use your meter.

What is Hemoglobin A1C?

Hemoglobin A1C is a lab test. It indicates an average blood glucose reading for the last 90 days. It is done when you find out you have diabetes, and every 3 months after that at clinic visits. A person without diabetes has a Hemoglobin A1C of less than 5.6%.

Target Hgb A1C is 7.5% for all children and adults with diabetes.

The chart below shows the Hemoglobin A1C result compared with the blood glucose number.

Download the Diabetes Blood Glucose/Insulin Record 

Back to the Managing Your Diabetes Resource Book Table of Contents

Why should I know my blood sugar levels?

Our Associate Medical Director Dr Mike Knapton tells Senior Cardiac Nurse Emily Reeve why it can be important to know your numbers.

Why do my blood sugar levels matter? 

We all need sugar in our blood to provide cells with energy. The hormone insulin allows sugar (glucose) in your bloodstream to enter your cells, where it can used for energy. If you don’t have enough insulin, sugar stays in the bloodstream. Over time, high blood sugar levels damage your blood vessels. This can cause other problems, such as coronary heart disease, kidney disease and diabetic eye disease.It’s important to know whether you have high blood sugar so that this can be controlled, reducing the risk of damage.

If you don’t have enough insulin, sugar stays in the bloodstream

A high blood sugar level would mean you either have diabetes (type 1 or type 2) or have a high risk of developing type 2 diabetes. Although diabetes can have symptoms, such as thirst, urinating a lot, blurred vision, weight loss, recurrent infections and tiredness, you may only get these mildly, or not at all. That’s why it’s important to get tested.

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If I’ve had a heart attack, should I get my blood sugar checked?

If you have heart and circulatory disease, this should be done as part of your routine blood checks. If you are concerned, talk to your GP.

What about people who don’t have any existing conditions?

If you are at risk, your blood sugar will be tested as part of an NHS Health Check in England (for those aged 40–74 with no existing condition). Arrangements vary in the rest of the UK, but again, ask your GP if you are concerned.

Am I at risk of diabetes?

Any of the following can mean you’re at risk, especially if more than one of these applies:

  • being over the age of 40
  • south Asian, Chinese, African-Caribbean or black African background
  • a close relative has diabetes
  • overweight or large waist size
  • high blood pressure
  • pregnancy or previous gestational diabetes
  • polycystic ovary syndrome, schizophrenia, bipolar illness or depression, or you are taking antipsychotic medication.

Learn more about your diabetes risk using the Diabetes UK online tool.

What if I have diabetes?

Monitor your blood sugar levels at home using a glucose meter. This involves pricking your finger and applying a drop of blood to a test strip.

Self-monitoring can be a helpful part of diabetes management. Regular blood sugar tests help you see how specific changes, for example around diet and physical activity, affect blood sugar levels. Monitoring can also help your healthcare team adjust your treatment to best prevent any long-term complications. Your doctor should also check HbA1c levels at least yearly to assess long-term blood sugar control

What do my blood sugar numbers mean?

Self-monitoring can be a helpful part of diabetes management

Persistently high blood sugar usually means you have diabetes. If HbA1c is more than 48 mmol/mol or fasting blood glucose is more than 11 mmol/L, your blood sugar is high. For most people without diabetes, normal blood sugar levels are: 

  • between 4 and to 6 mmol/L before meals
  • less than 8 mmol/L two hours after eating.

If you have diabetes, it’s key for your blood sugar levels to be as near normal as possible.

How is blood sugar measured?

Your GP can test your blood for a substance called HbA1c (glycated haemoglobin), to diagnose type 2 diabetes, or to monitor long-term blood sugar control if you have diabetes. This is different from the finger-prick blood sugar test.

Measuring HbA1c gives a picture of your average blood sugar levels over the past eight to 12 weeks. If you have diabetes, your HbA1c should be tested every three, six or 12 months. The higher the HbA1c, the greater the risk of developing complications.

The test for gestational diabetes is a bit different and is called an oral glucose tolerance test. Usually you’ll be given a glucose drink and your blood sugar will be tested before and after.

Understanding blood glucose (blood sugar)

Blood sugar factActions school staff can take

Low blood sugar (less than 4.0 mmol/L) is an emergency and must be treated right away

High blood sugar with symptoms of illness needs attention

  • Learn about high blood sugar (hyperglycemia).
  • Ensure this poster on high blood sugar is visible in your school.
  • Know what to do when a student is not well.

Food raises blood sugar

  • Advise parents in advance if there will be a special event involving food.
  • Advise parents if you expect changes to the lunch or snack schedule.

Physical activity lowers blood sugar

  • Advise parents in advance of an additional activity (such as a Terry Fox Run, extra gym time, field trip, dance-a-thon, walkathon).
  • Advise parents if you expect changes to the schedule for physical education classes.
  • Allow students to have extra snacks for activity as needed (see their Individual Care Plan for guidance).
  • Have an emergency kit available for treating lows during gym classes.

Insulin lowers blood sugar

Don’t assume that a student with diabetes can’t have a special treat. They may just need some extra insulin, or to include the treat into their meal plan for that day. Planning ahead can ensure they are included.

Low blood sugar can affect a person’s thinking

Allow a student extra time if they have a low blood sugar before or during a test/exam. They may need up to an extra 30 to 60 minutes to treat and recover from the low.

High blood sugar causes thirst and more frequent urination

  • Ensure students with type 1 diabetes always have unrestricted access to water and to the bathroom.
  • If you see these symptoms in a child without diabetes, inform the parents and suggest they see a doctor.

High blood sugar will affect a student’s ability to concentrate and to learn

  • If students administer insulin at school, ensure they are able to do so as needed.
  • But do not make assumptions. There may be other reasons a student cannot concentrate (lack of sleep, for example). If you notice changes in a student’s behaviour, the first step is to check blood sugar.

A blood sugar reading is a number, a piece of information. It is neither “good” nor “bad”.

  • Be objective and non-judgmental about blood sugar readings. Avoid criticism.
  • Refer to blood sugar “checks” and not “tests”. It’s important for children and youth with diabetes to know that they are not being judged when their blood sugar is checked.