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Checking Your Blood Sugar

Checking Your Blood Sugar

Living well with diabetes means knowing how food, activity, and diabetes medications affect your blood sugar. Checking your blood sugar regularly provides information you can use to adjust eating habits and activities to manage your diabetes.

What numbers are right for you?

Blood sugar goals vary from person to person. Talk to your health care team about your goals and what is best for you.




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Getting started

Your health care team can help you decide if and when to check your blood sugar. They can provide a blood sugar meter and instructions on how to use it.

When to check

Work with your health care team to make a plan for testing your blood sugar. Common times to check are:

  • When you first wake up and before you eat (fasting)
  • Before meals
  • 2 hours after the start of a meal
  • At bedtime

Different ways to check your blood sugar

Blood sugar meterBlood sugar meters are small devices used to check blood sugar levels. The results show the amount of sugar in the blood at the time of the test.


Continuous Glucose MonitoringContinuous Glucose Monitoring (CGM) uses a tiny sensor under the skin to check blood sugar levels every 1 to 5 minutes, 24-hours a day. CGM devices can be linked to a cell phone.


A1CHemoglobin A1C is a lab test that measures your average blood sugar level over the past 2 to 3 months.

Goals for Blood Sugar* My Blood Sugar Goals
Fasting or before a meal: 80 to 130 mg/dl  
2 hours after meals: Below 180 mg/dl  
A1C: Less than 7% for most adults  
* These are general recommendations for people with diabetes who are not pregnant.

Blood Sugar Highs and Lows

  High Blood Sugar Low Blood Sugar
What is it? Also known as Hyperglycemia.
May or may not have symptoms.
Also known as Hypoglycemia.
Usually lower than 70 or when having
symptoms of low blood sugar.
Why is it
High blood sugar can cause low energy
and long-term damage to eyes, kidneys,
feet, and other parts of the body.
Our brains need sugar to work well.
Low blood sugar can cause confusion
or fainting.
What are some
Weakness, blurred vision, thirst, or
urinating (peeing) often.
Hunger, confusion, dizziness, shakiness,
or fast heartbeat.
What to do? If your blood sugar is too high, drink
water and limit sugars and starches. Talk
to your health care provider.
Treat low blood sugar. Have a
sugary item, such as 4 oz. of juice, 4
glucose tabs, or 1 glucose gel. Retest
in 15 minutes.

If your blood sugar levels are too high or too low, you may need to make changes to:

Plate with spoon and fork resembling a clock

What or when you eat and drink

Rx medication bottles and medication


A woman exercising

Physical activity

A woman relaxing

Managing stress


Going UP

Things that may cause hyperglycemia

  • Eating more than usual or a large meal
  • Forgetting your diabetes medication
  • Dealing with stressful situations
  • Having an illness or infection

Going DOWN

Things that may cause hypoglycemia

  • Eating less than usual or skipping meals
  • Being more active than usual
  • Taking more medication than prescribed by your provider