To find out how and why your blood sugar levels fluctuate, you must measure it regularly at key times throughout the day with the help of a blood glucose meter, such as the BGStar which is very easy to use or the iBGStar which is compatible with the iPhone or iPod Touch.
Fasting Blood Glucose (FBG)
Measures blood glucose after you have not eaten for at least 8 hours (for example, before breakfast).
Pre-Meal Blood Glucose
Measured immediately before you eat.
Post-Prandial Glucose (PPG)
Measures blood glucose after you eat a meal. When you measure PPG, your reading should be done 2 hours after you took your first bite of the meal, and not 2 hours after you finished eating the meal.
The Importance of FBG and PPG on Glycosylated Hemoglobin (A1C)
The FBG and PPG both have a determining effect on glycosylated haemoglobin (A1C), a measure of your average blood glucose control over the past 2-3 months. This blood analysis can only take place in a laboratory and 50% of the value comes from the last 30 days.
Pre-meal blood glucose, post-prandial glucose and A1C are three important measurements for your diabetes control and all have recommended targets.
Blood Glucose Targets
The Canadian Diabetes Association has recommended targets for your blood glucose. It’s really important that you try to keep your blood glucose as close to the target range as possible. By doing this, you may reduce complications associated with diabetes (eye problems, foot problems, kidney disease, nerve problems, heart and blood vessels). The targets shown in the table below are ranges for most people living with diabetes. Your health professional may recommend more specific targets for you.
The Canadian Diabetes Association recommended blood glucose targets for people living with diabetes
|Based on blood work done in a clinic or lab||Based on your values from your blood glucose monitor|
|A1C *||Fasting blood glucose/Blood glucose before meals||Blood glucose two hours after eating|
|Target for most people with diabetes||Less than or equal to 7.0%||4.0-7.0 mmol/l||5.0-10.0 mmol/l (5.0-8.0 mmol/l if A1C targets not being met)|
*A1C is a measure of your average blood glucose control over the past 2-3 months. 50% of the value comes from the last 30 days
How to Achieve Your Glycemic Target: Blood Glucose Pattern Management
Blood glucose pattern management involves 5 steps to make sense of your blood glucose and treatment plan. Designed to help you achieve your blood sugar targets to reduce diabetes complications, it allows you to understand how your daily decisions affect your blood glucose.
The STARsystem website offers a Pattern Management Tool to help you walk through these 5 steps.
Record your blood glucose for 3 days at the following times: before meals, 2 hours after the start of eating meals, and at bedtime.
- Review and Recognize:
Review your blood glucose levels, highlight any out-of-target blood glucose results, and try to recognize if there is a pattern of highs or lows.
Refer to section 3 of the Pattern Management Tool to help you find the reason for the pattern(s).
Make adjustment(s) to remove one pattern at a time in the following order:
- First - fix low blood glucose (any pattern of blood glucose results less than 4 mmol/l).
- Second - fix high blood glucose before breakfast or before meals (any pattern of blood glucose results higher than 7 mmol/l before meals).
- Third - fix high blood glucose after meals (any pattern of blood glucose results higher than 10 mmol/l when checked 2 hours after the start of eating your meals).
Reassess by checking your blood glucose at specific times to see if you have removed the pattern.
Take the time to write down your blood glucose levels.
Self-monitoring of blood glucose (SMBG) is very important because it shows more precisely how your readings go up and down during the course of a day. Depending on your blood glucose patterns and management plan, you and your healthcare team can determine the best times for checking your blood glucose readings to improve your A1C and reduce your risk of developing the complications associated with diabetes.
By mastering your diabetes management, you will be in a better position to control your diabetes, meaning able to achieve your blood sugar targets to possibly prevent diabetes complications. Having a good understanding of your blood glucose will help you and your healthcare team make decisions about your diabetes management plan.
If you are having trouble figuring out the reason for your out-of-target blood glucose patterns, speak with your healthcare team.
What Happens If I Don’t Reach My Target Range?
When blood glucose drops below 4 mmol/l it’s called hypoglycemia. This can occur in people taking medicine that stimulate the production of insulin by the pancreas, or in people taking insulin. Conversely, when blood glucose levels are higher than your target range, it’s called hyperglycemia.
Hypoglycemia can be caused by:
- Doing more physical activity than usual
- Vomiting or diarrhea
- Fasting and taking full doses of medication for diabetes
- Eating too little food
- Missing or delaying meals
- Taking too much medication
- Alcohol intake
There are different stages of hypoglycemia: mild, moderate and severe.
Mild and moderate hypoglycemia can cause the following symptoms:
- Palpitations (fast heartbeat)
- Difficulty concentrating
- Vision changes
- Difficulty speaking
Sometime you may have a low blood glucose level when you are sleeping, the symptoms of low blood sugar during sleep can be different and include:
- Restless sleep
- Night sweats
- Awakening from sleep
- Waking up with a headache
What to do if you think you are having a low blood sugar reaction:
- Check your blood glucose — if you are unable to check your blood sugar and you think you are having a low blood sugar you should treat your symptoms
If your blood glucose is less than 4 mmol/l, eat a rapid-acting carbohydrate:
- 15 g of glucose in the form of glucose tablets
- 15 mL (3 teaspoons) of table sugar dissolved in water
- 175 mL (3/4 cup) of juice or a regular (not diet) soft drink
- 6 Life Savers candy
- 15 mL (1 tablespoon) of honey
Retest in 15 minutes. If your blood glucose level is still under 4 mmol/l, repeat.
Once your blood glucose level is over 4 mmol/l, you need to eat something within the hour. If you have a meal coming up then you don’t need to worry. However, if you won’t be eating a meal within an hour, eat a snack containing carbohydrate and protein to tide you over until your meal.
- 1 slice of bread
- ½ cup of cereal
- 7 crackers
- 1 oz. of cheese (1 inch cubed)
- ¼ cup of nuts
- 2 tbsp. peanut butter
Severe hypoglycemia is when your blood glucose falls below 2.8 mmol/L. If you experience severe hypoglycemia, you may need the help of another person to treat it, and you could become unconscious.
If you have severe hypoglycemia (blood glucose less than 2.8 mmol/l), you must take 20 g of glucose in the form of glucose tablets right away. It is important that your family and friends know how to treat a low blood glucose level if you become unconscious. In some cases, an injection of glucagon may be necessary.
Hyperglycemia can be caused by:
- Overeating, or eating more than usual
- Missing a dose of medication or insulin
- An out-of-the-ordinary event (for example, illness, stress, excitement)
- A sudden mood change (for example, extreme fright, anger or sadness)
- Less activity than normal
If you experience hyperglycemia, you might experience:
- Extreme thirst
- More frequent urination
- Dry and flushed skin
- Mood swings
- Unusual fatigue
- Weight loss
When your blood glucose levels are very high, your body tries to get energy from the fat and muscle in your body. When this happens, and the body starts to break down fat and muscle, it produces something called ketones. Your body tries to get rid of ketones by passing them through your kidneys and out in the urine. Ketones in combination with high blood glucose can cause something called diabetic ketoacidosis (or DKA, for short), which is a medical emergency.
Diabetic Ketoacidosis (DKA)
It’s very rare for people living with type 2 diabetes to develop DKA, but you should be aware of the signs, just in case. If you suffer from type 1 diabetes, your risk of developing DKA is higher. People living with type 1 diabetes should be able to test for ketones at home. This can be done by testing your urine or using a blood glucose monitor that can measure ketones.
Symptoms of DKA can include:
- Frequent urination or thirst for more than a day
- Nausea and vomiting
- Stiffness or aching in the muscles
- Rapid breathing
- Breath that smells "fruity"
- Loss of consciousness
- Difficulty breathing when lying down
- Abdominal pain
DKA is a medical emergency, so if you suspect that you have symptoms, ask someone take you to the nearest hospital emergency room or call an ambulance immediately.