Diabetes Monitoring: Why, How, and When to Check Your Blood Sugar

Introduction to Blood Sugar Monitoring

Understanding the Importance of Checking Blood Sugar Levels

Monitoring our blood sugar (or blood glucose) levels is of utmost importance for persons with diabetes. Blood sugar level refers to the amount of sugar present in your blood, which fuels our bodies to carry out day-to-day activities. Any fluctuation in this level, whether too high (a state referred to as hyperglycemia) or too low (hypoglycemia), can lead to adverse health complications. Regular monitoring of blood sugar can help you avoid these risks and maintain an overall healthy life.

In managing diabetes, monitoring your blood sugar levels is integral to maintaining a healthy lifestyle. It aids in discerning when to adjust your medication intake, meals, and physical activity. Regular checking of blood sugar levels can also help you observe symptoms of hypo- or hyperglycemia, manage these problems and prevent them in the future..

Defining Various Aspects of Blood Sugar Monitoring

Blood sugar monitoring refers to the practice of regularly checking your glucose levels. It involves the use of a glucose meter (glucometer) or a continuous glucose monitoring (CGM) device to achieve real-time snapshots of sugar levels in your blood. Monitoring helps to understand how various factors like food, physical activity, medication, stress, and illness can impact your blood sugar levels. It’s essential for managing diabetes effectively and helps you to make important decisions about nutrition, physical activities, and when to take medications.

The Essentials of Monitoring Blood Sugar

Why Monitor Blood Sugar?

Regular monitoring of your blood sugar is crucial in managing diabetes efficiently. Here's why:

  • Detect Highs and Lows: Monitoring helps you identify times when your blood sugar is too high or too low, allowing you to act quickly and avoid the health risks associated with them.
  • Evaluate Treatment Efficiency: It helps assess if your current diabetes treatment plan, medications, or insulin are effective in maintaining your blood sugar levels.
  • Understand the Impact of Lifestyle Choices: It shows how the foods you eat, the exercises you do, and other lifestyle factors affect your blood sugar levels, enabling you to make healthier choices.
  • Track Progress: Regular readings let you track your progress towards achieving your overall treatment and health goals.
  • Plan Ahead: By understanding how different factors affect your levels, you can predict and prepare for blood sugar fluctuations ahead of time.

Regular blood sugar testing is a practical tool allowing you to actively participate in your own diabetes management and live a healthier life.

When Should You Check Your Blood Sugar?

The frequency and timing of blood sugar tests generally depend on the type of diabetes you have, how well controlled it is, and your overall health. Your healthcare provider will give you the most precise guidelines for testing.

However, here are some general times when you should consider checking your blood sugar:

  • Before Meals and Snacks: This can help you decide what to eat and how much insulin to take if you're on insulin therapy. If you take a reading before you eat breakfast this is known as a 'fasting blood glucose' readings and is
  • After Meals: Checking your blood sugar two hours after the start of a meal can provide information about how your body handles different types of food.
  • Before Physical Activities: If you have diabetes, exercise could affect your blood sugar levels. Checking before physical activities will help you prevent hypoglycemia.
  • Before Bed: Monitoring your blood sugar levels before sleep helps you adjust your evening or nighttime insulin dosage.
  • During Illness: Illness tends to increase your body's production of stress-related hormones that work against insulin and cause your blood sugar to rise.
  • More frequently if: You have just had surgery, experiencing frequent low blood sugar episodes, have started a new medication, or are pregnant.

Remember, checking blood sugar doesn't only mean testing for high levels. Hypoglycemia, or low blood sugar, can be equally, if not more, dangerous. Thus, it's essential to test your blood sugar whenever you feel "low" symptoms or sense that your levels may be off.

Reading and Analysing Your Blood Sugar Levels

Understanding how to read and analyse the blood glucose results generated by your glucose monitoring device is crucial for managing your diabetes effectively. Here are a few points to keep in mind (note that there are 2 units of measure for blood glucose: mmol/L (used in Singapore) and mg/dl (used on some other countries including the US). We present blood glucose ranges and targets mmol/L in this article.

  • Know Your Target Range: Standard blood glucose targets from Singapore Ministry of Health's Clinical Practice Guidelines for diabetes are 4-7 mmol/L before meals, and less than 10 mmol/L two hours after the start of a meal. However, the recommended range can vary depending on a variety of factors, including age, overall health, and how long you've had diabetes. Your healthcare provider should provide a target range that's tailored to your needs.
  • Track Your Patterns: Look for patterns or consistent trends across multiple blood sugar readings rather than focusing on individual readings. For instance, consistently high blood sugar levels in the morning may be a sign of the 'dawn phenomenon' requiring changes to your medication dosage.
  • Consider Other Factors: Remember that other factors like food, physical activity, medication, stress, and illness can influence your blood sugar levels. Consider these factors when analyzing your results.
  • Record Your Results: Keep a log of your blood sugar levels. Recording your results and the conditions at the time of testing (like food intake, activities, etc.) can help you and your healthcare provider understand how well your diabetes management plan is working and what changes might need to be made. Recording your data through a diabetes app is ideal.

Remember, it's essential to discuss your blood glucose readings and any concerns with your healthcare team, who can help interpret your results and guide you on necessary adjustments to your diabetes management plan.

What's HbA1c?

HbA1c, also known as glycated haemoglobin, is a key medium-term diabetes monitoring measurement. This blood test is a measure of your average blood glucose levels over the prior two to three months, in contrast to single blood glucose readings, which measure your blood glucose at a single point in time.

HbA1c operates by measuring the percentage of your hemoglobin - a protein in red blood cells that carries oxygen - that has been coated with sugar (glycosylated). The higher the HbA1c level, the poorer your blood sugar control and the higher your risk of diabetes complications. An HbA1c level of 5.7% to 6.4% signifies prediabetes, indicating a heightened risk for developing full-blown diabetes. On the other hand, a level of 6.5% or higher confirms a diagnosis of diabetes.

This blood test doesn't require fasting requires you to submit a blood sample, which is sent to a lab for analysis. It is recommended that, for most patients with diabetes, an HbA1c test is done every 3 months, although some individuals might need more frequent testing. This allows you and your healthcare team to spot and respond to trends over time, enhancing the effectiveness of your treatment plan and lessening the risk of serious complications.

Most patients with diabetes will be set a target HbA1c level, typically 7% or 6.5%. If your current HbA1c is higher than this, you and your healthcare team should try to adjust your lifestyle and/or medications to bring this down to target over time.

Remember that there are factors that might lead to an unreliable A1C result, such as certain conditions related to hemoglobin such as sickle cell anemia. In these situations, it's important to work with your healthcare professional to determine the best glucose monitoring methods and goals suitable for you.

Different Types of Blood Sugar Monitoring

Exploring Traditional Blood Glucose Meters

When it comes to checking your blood sugar at home, traditional blood glucose meters (glucometers) are a widely used option. They are small, portable devices that measure glucose levels in a small sample of blood obtained by pricking your finger.

Blood is captured on test strips, which are specific for your glucometer and made by the manufacturer of your glucometer - so for regular glucose monitoring you need both a glucometer and test strips. Make sure your test strips are not past their expiry date to ensure accurate readings.

Glucometers are often sold together with sterile blood lancets - spring-loaded finger pricking devices which help you to get a drop of blood with the least pain possible. Finger pricking is really not so painful once you get used to it!

There are several types of blood glucose meters available, each with unique features catering to different user needs. For example, some meters are faster than others to generate reading values. All offer ways to store the time and value of past readings and some allow syncing of this data to external diabetes apps ands other systems. Based on this data, such systems can provide fact-driven feedback to patients and their healthcare team to help improve diabetes management.

Here are examples of popular glucometer models available in Singapore from your pharmacy or through online retailers:

While selecting a blood glucose meter, consider factors like cost, ease of use, testing speed, size, and additional features to make the most suitable choice for your needs. Always remember to discuss your options with your healthcare professional before deciding.

Continuous Glucose Monitors and Flash Glucose Monitoring

Continuous Glucose Monitors (CGM) and Flash Glucose Monitors (Flash GM) are advanced technologies that offer real-time, continuous monitoring of glucose levels, providing a more comprehensive picture of your glucose dynamics.

Dexcom G^ Continuous Glucose Monitoring system


These devices measure glucose levels in your body interstitial fluids continuously throughout the day and night through a sensor that you insert under your skin. Newer CGM devices, such as the Dexcom G6, can transmit your CGM glucose reading directly to a smartphone app or receiver. They also display glucose trends and can even alert you if your glucose levels get too high or too low. This real-time feedback can help individuals with diabetes to make more informed decisions about food intake, insulin doses, and other lifestyle factors.

Flash Glucose Monitors, like Abbott's Freestyle Libre, are similar to CGMs but require patients to scan the sensor with a scanning device in order to upload data to the cloud, where it is securely and confidentially stored. By combining data from scans, continuous glucose monitoring can be achieved which can show you in detail how your blood sugar level changes during the day and night.

Freestyle Libre Flash Glucose Monitoring device

Sample Freestyle Libre Ambulatory Glucose Profile

Both CGM and Flash GM sensors are typically replaced every 10-14 days and can be worn while bathing, swimming, and exercising, making them a convenient choice for continuous monitoring. By wearing a CGM or Flash GM, people with diabetes can achieve a better understanding of their glucose patterns and variations, leading to improved diabetes control.

CGM devices have been shown to be safe and effective in improving blood sugar control in both type 1 and type 2 diabetes. However, in view of their cost and complexity, CGMs and Flash GMs are more suitable for patients who need closer, more frequent monitoring - for example if they have type 1 diabetes, are poorly controlled or undergoing changes in medication. CGM and Flash GM are not meant to completely replace traditional blood glucose testing but rather to complement it. It's essential to confirm suspicious or critical readings with a traditional blood glucose meter. So a combination of CGM/Flash GM and traditional finger prick glucose monitoring is often the best solution. Always discuss your options with your healthcare professional before making a choice.

How to Use a Traditional Blood Glucose Meter

Step-by-step Guide on Testing Blood Sugar

This video from SingHealth Polyclinics provides a detailed guide on using a glucometer and test strips:


Testing your blood sugar at home is a straightforward process that becomes routine with a bit of practice. Here's a step-by-step guide on how to measure blood glucose using a traditional blood glucose meter:

  1. Wash Your Hands: Your hands should be clean before handling your testing supplies. Any residual substance on your hands may contaminate the testing area and give false readings.
  2. Insert Test Strip: The test strip should be inserted into the designated slot on the glucose meter. The device should be turned on either automatically or manually, depending on your meter's instructions.
  3. Prick Your Finger: Use a lancing device (included in most glucose meter kits) on the side of your fingertip to draw a small drop of blood. Pricking the side of the finger instead of the tip reduces pain and still provides an ample drop of blood for testing. If need be, you can gently squeeze your finger until a small drop forms.
  4. Apply Blood to Test Strip: Touch and hold the edge of the test strip to the drop of blood. The blood will be drawn into the tiny channel in the strip. Ensure that enough blood has been applied to fill the channel completely.
  5. Wait for the Result: The meter will then calculate your blood glucose level, usually in just a few seconds. The reading will appear on the device's digital display.

Remember, all meters are slightly different, so always refer to your user's manual for specific instructions. Although finger-prick testing may seem daunting initially, it quickly becomes part of a normal routine. It's crucial that you receive proper training on how to do the test and use your meter correctly — otherwise, you could get the wrong results.

Key Tips on Avoiding Problems with Your Meter

To maintain the accuracy and reliability of your blood glucose meter, follow these tips:

  1. Use the Correct Test Strips: Use only test strips designed for your meter. Using the wrong strip for the meter can lead to inaccurate readings.
  2. Proper Storage: Store your test strips as per the manufacturer's guidelines to prevent them from getting damaged. Avoid keeping them in extreme temperatures or high humidity.
  3. Check Expiry Date: Avoid using expired test strips, as they may not give accurate readings.
  4. Maintain Meter Well: Clean the device and run quality-control checks as directed. Not doing so might affect its performance or even damage it.
  5. Battery Maintenance: Regularly check and replace your glucose meter's batteries. A low battery may affect the device's accuracy.
  6. Code Your Meter Correctly: Some glucose meters need to be coded to each batch of test strips. Make sure the code on the meter matches the code on the strip container.
  7. Avoid Inaccurate Readings: Ensure you wash your hands before testing. Residual substances on your hand might distort the reading.
  8. Sufficient Blood Sample: Ensure you put a sufficient amount of blood on the test strip. Too little or too much might result in an inaccurate reading.

Regular meter checks and maintenance are key to avoid inconsistencies and inaccuracies in your readings. Always keep in mind that your meter is a crucial tool for maintaining good control over your diabetes. So, you must familiarize yourself thoroughly with how to use it correctly.

Recording Your Results for Better Diabetes Management

Keeping a detailed log of your blood glucose readings is a beneficial practice. Recording your blood sugar levels can help both you and your healthcare team understand how well your diabetes management plan is working and what adjustments might be necessary.

Here are some ways to record your results:

Paper Diary: Some people prefer a traditional approach and write their blood glucose levels in a dedicated diabetes diary or notepad. Record the date, time, test results, medication and dose, and diet and exercise information.

Phone Apps: With growing technology, numerous diabetes logging apps can help record, track and analyse your blood glucose readings, insulin doses, meals, activities, and more. Some meters can even transmit your readings directly to your smartphone via Bluetooth.

Meter Software: Many meters come with associated desktop software, which allows you to upload your readings onto your computer. This software usually offers visualization tools to help you identify trends and patterns.

Logging your Blood Glucose Readings and Tracking 2-Week Indicators in trhe SugoSure patient app

Whichever method you choose, be sure to record your blood sugar levels consistently. Keep a note of any unusual readings and try to identify any potential triggers or causes. Bring your log or device storing the readings to your healthcare appointments, and discuss your readings and any related questions or concerns with your healthcare provider.

Remember, the key to effective diabetes management lies in learning from your past readings and adjusting your lifestyle and treatment accordingly. Monitoring your blood glucose levels and recording these readings play a critical role in achieving good diabetes control.

Interpreting Your Blood Glucose Readings and Adjusting Your Lifestyle

Understanding the Meaning of Your Blood Glucose Readings

Understanding your blood glucose reading is key to managing diabetes effectively. Different levels of blood glucose can imply different things:

  • Normal blood glucose: Standard blood glucose targets are 4-7 mmol/L before meals, and less than 10 mmol/L two hours after the start of a meal.
  • High blood glucose (Hyperglycemia):Pre-meal blood glucose levels above 7 or 2 hour post-meal levels of >10 mmol/L are considered high (hyperglycaemia). Prolonged high blood sugar can damage blood vessels, nerves, and organs.
  • Low blood glucose (Hypoglycemia): If your glucose falls below 4 mmol/L it signifies hypoglycemia. It can be dangerous because glucose is the primary fuel source for your brain. Symptoms include dizziness, confusion, shaking, and even unconsciousness in severe cases.
  • Pre-meal and post-meal variations: Your blood sugar levels are expected to rise after eating and decrease after exercise or insulin administration. Thus, readings should always be interpreted in the context of your last meal, physical activity, and medication timing.

Remember, if the same thing (high or low blood sugar) keeps happening, it might be time to change your diabetes care plan. Work with your doctor or diabetes educator to learn what your results mean for you. It can take time to make adjustments and get things just right. And do ask your doctor if you should report results out of a certain range right away by phone. It's vital to not rush into conclusions from a single reading. Always track your patterns and understand the context before making any adjustments to your diabetes plan.

Evaluating the Causes of High or Low Blood Glucose Readings

Understanding the causes of hyperglycemia (high blood glucose) and hypoglycemia (low blood glucose) can help regulate your sugar levels effectively.

High Blood Glucose (Hyperglycemia) can be caused by:

  • Consuming more carbs than your body can handle
  • Not taking enough diabetes medication or insulin
  • Irregularity in maintaining a medication schedule
  • Physical stress, like illness or infection
  • Emotional stress, such as family conflicts or school pressures
  • Other medications

Low Blood Glucose (Hypoglycemia) can be caused by:

  • Taking too much insulin or other diabetes medications
  • Missing or delaying a meal
  • Eating less than usual
  • Increasing physical activity level without adjusting medication or food intake
  • Consuming alcohol, which can lower blood sugar levels

Being aware of these triggers allows better control over your glucose levels and aids in making timely adjustments to your food, activity, and medication. Both conditions bring about specific symptoms. For instance, hyperglycemia might cause frequent urination, excessive thirst, or tiredness, whereas hypoglycemia might lead to shaking, dizziness, or even fainting. Observing such symptoms and taking timely action is crucial in managing your diabetes effectively. Do remember to seek medical attention if conditions persist or worsen.

Using Your Learnings for Better Diabetes Self-Management

Blood glucose readings analysed an displayed in the SugoSure patient app


Decoding your patterns in blood glucose readings and adjusting your lifestyle accordingly is crucial in diabetes self-management. Here's how:

Adjusting your diet: Noticing a trend of high blood glucose levels after eating certain types of food may indicate a need for dietary modifications. Similarly, if you find you regularly experience low blood sugar levels before meals, it might suggest that you need to eat more frequently.

Modifying medication: If you're consistently having high blood sugar, even after careful management of diet and exercise, you may need to speak with your healthcare provider about adjusting your medication dosage.

Altering exercise routines: Regular physical activity is an important part of diabetes management. However, if you frequently experience hypoglycemia during or after exercise, you may need to adjust your workout routine or meal plan.

Stress management: Stress hormones can cause blood sugar to rise. If you notice a correlation between high stress periods and elevated blood glucose, consider strategies for stress reduction, such as practicing mindfulness, meditation, or yoga.

Adhere to a routine: Try to eat at the same time each day and stick as closely as possible to your medication schedule.

Remember, managing diabetes isn't a 'one size fits all' approach. It often requires adjustments and changes over time. Continuous monitoring and learning from your glucose readings, then tailoring your diabetes plan to meet these observations is key to success. Always discuss any changes in your routine with your healthcare provider to ensure you're managing your diabetes in the best way possible.

How Technology Can Help You Use Your Monitoring Data More Effectively

Diabetes is a data-rich condition and if you regularly self-monitor, you may generate so much data that kt becomes hard for you to evaluate and analyse what it all means.

This is where technology has an increasingly important role: the best diabetes management systems use your monitoring data to help you in several ways:

  1. Acting as a guide to help you take blood glucose readings and other diabetes measures at the right times
  2. Analysing your data and highlighting trends and issues which may need closer attention from you and your healthcare team
  3. Allowing remote monitoring of your condition by making your data available in a secure way to your healthcare team so that any problems can be quickly fixed
  4. Connecting you with your healthcare team for tele-consultations to discuss your progress or deal with problems

While there are many diabetes apps available, they range in function from simple electronic notebooks to more sophisticated diabetes management systems such as SugoSure, which supports you in all the ways described above.

SugoSure's comprehensive and clinically-validated approach is designed to provide the guidance and support you need to take control of your diabetes through monitoring and lifestyle changes.

To get started, go to www.sugosure.com to learn more about SugoSure’s complete approach to diabetes management. Watch our videos and see how SugoSure helps you with monitoring your diabetes. Then start the sign-up process by completing a short Diabetes Assessment.

The SugoSure app is available on Google Play and Apple App Store.