Are You Checking Your Blood Sugar Correctly? Common Mistakes to Avoid

17 Sep 2025 By Rozalina G. McCoy, M.D., M.S.

Are You Checking Your Blood Sugar Correctly? Common Mistakes to Avoid

Managing blood sugar levels is a critical aspect of diabetes care. Regular blood sugar monitoring helps individuals understand how diet, exercise, medication, and stress affect their glucose levels. However, many people make common mistakes when checking their blood sugar, which can lead to inaccurate readings and potentially harmful health decisions. This article highlights these mistakes and provides actionable steps to ensure accurate blood sugar testing. The Complete Guide To Your A1C Test And What It Means For You

Why Accurate Blood Sugar Monitoring Matters

Accurate blood sugar monitoring is essential for several reasons:

Effective Diabetes Management: Knowing your blood sugar levels helps you make informed decisions about medication dosages, meal planning, and physical activity.
Preventing Complications: Consistent and accurate monitoring can help prevent both short-term complications (hypoglycemia and hyperglycemia) and long-term complications (nerve damage, kidney disease, heart disease).
Personalized Treatment Plans: Accurate data allows healthcare providers to tailor treatment plans to meet individual needs effectively.

Common Mistakes in Blood Sugar Monitoring

One of the first steps to properly manage diabetes and blood sugar levels is by testing them frequently. However, certain things could cause inaccurate results. This section explains these mistakes so you can adjust how you test your blood sugar levels.

1. Using Expired or Damaged Test Strips

The Problem: Test strips have expiration dates because the chemicals they contain can degrade over time, leading to inaccurate results. Damaged test strips may also produce unreliable readings.

The Solution: * Check Expiration Dates: Always verify the expiration date on the test strip vial before using them. Discard any expired strips. * Store Properly: Store test strips in their original, tightly closed container to protect them from moisture and extreme temperatures. * Inspect for Damage: Before using a test strip, examine it for any visible damage or discoloration.

2. Improper Hand Hygiene

The Problem: Contaminants on your hands, such as food residue, lotions, or even water, can interfere with the blood sample and give false readings.

The Solution:

Wash Your Hands Thoroughly: Wash your hands with soap and warm water before checking your blood sugar. Dry them completely.
Avoid Alcohol-Based Sanitizers: While hand sanitizers are convenient, they can affect blood glucose readings. If you use sanitizer, make sure it is completely dry before testing.
Rinse and Dry: If using soap is not possible, rinse your hands thoroughly with water and dry them completely.

Example: A study published in the Journal of Diabetes Science and Technology found that washing hands with soap and water reduced the risk of inaccurate readings by 30% compared to using alcohol-based sanitizers.

3. Using an Incorrect Blood Sample Size

The Problem: Most glucose meters require a specific amount of blood to provide an accurate reading. If the sample is too small, the meter may display an error or give a falsely low result.

The Solution:

Ensure Adequate Blood Flow: Before lancing your finger, gently massage the area to encourage blood flow.
Use a Lancing Device: Lancing devices allow you to control the depth of the puncture, ensuring you obtain an adequate blood sample.
Re-test if Necessary: If the meter displays an error message related to insufficient blood, discard the test strip and repeat the test with a new strip and a larger blood sample.

4. Not Calibrating the Glucose Meter

The Problem: Glucose meters need to be calibrated to ensure they provide accurate readings. Without proper calibration, readings can drift over time.

The Solution:

Use Control Solutions: Periodically use control solutions to check the accuracy of your meter. Follow the manufacturer's instructions for using control solutions.
Compare with Lab Results: During doctor visits, compare your meter readings with laboratory blood glucose tests to identify any significant discrepancies.
Replace When Necessary: If calibration issues persist, consider replacing your glucose meter.

Example: Most manufacturers recommend using control solutions at least once a month or whenever you open a new vial of test strips. The Best And Worst Drinks For Maintaining Stable Blood Sugar Levels

5. Lancing the Wrong Finger Area

The Problem: The sides of your fingertips have fewer nerve endings and are less sensitive to pain. Lancing the center of the fingertip can be more painful and may not yield enough blood.

The Solution:

Lance the Side of the Fingertip: Puncture the side of your fingertip rather than the center.
Rotate Fingers: Use different fingers each time you test to avoid soreness.
Adjust Lancing Depth: Experiment with different lancing depths to find the setting that provides enough blood without causing excessive pain.

6. Neglecting to Keep the Meter Clean

The Problem: Dirt, dust, and blood residue can accumulate on the glucose meter, affecting its accuracy and functionality.

The Solution:

Clean Regularly: Clean your meter regularly with a soft, damp cloth. Avoid using harsh chemicals or abrasive cleaners.
Follow Manufacturer Instructions: Refer to the manufacturer's instructions for specific cleaning recommendations.
Store in a Clean Case: Keep your meter in a protective case to prevent dust and debris from accumulating.

7. Ignoring Environmental Factors

The Problem: Extreme temperatures and humidity can affect the performance of test strips and the meter itself, leading to inaccurate readings.

The Solution:

Maintain Proper Storage: Store your meter and test strips in a location with stable temperature and humidity. Avoid direct sunlight and extreme conditions.
Test in a Moderate Environment: When testing your blood sugar, do so in a room with a comfortable temperature and humidity level.

8. Failure to Consult with Healthcare Providers

The Problem: Many individuals attempt to manage their blood sugar without regular guidance from healthcare professionals. This can result in incorrect interpretations of readings and inappropriate treatment decisions.

The Solution:

Regular Check-ups: Schedule regular check-ups with your doctor or diabetes educator to review your monitoring techniques and results.
Discuss Concerns: Bring up any concerns or questions you have about your blood sugar monitoring process.
Adjust Treatment Plans: Work with your healthcare team to adjust your treatment plan based on your monitoring data.

Best Practices for Accurate Blood Sugar Monitoring

Here’s a summarized list of practices for when checking your blood sugar to avoid inaccurate results and get an efficient outcome every time:

Check Expiration Dates: Regularly verify and discard expired test strips.
Proper Hand Hygiene: Wash hands with soap and water, avoiding sanitizers.
Adequate Blood Sample: Ensure sufficient blood flow, re-test if needed.
Meter Calibration: Use control solutions regularly.
Correct Lancing: Puncture the side of the fingertip, rotate fingers.
Meter Cleaning: Clean regularly, follow manufacturer instructions.
Environmental Control: Store and test in moderate conditions.
Consult Professionals: Schedule regular check-ups for review and guidance.

Conclusion

Accurate blood sugar monitoring is an essential tool for managing diabetes effectively. By avoiding these common mistakes and following best practices, you can ensure that your blood glucose readings are reliable and that you are making informed decisions about your health. Regular communication with your healthcare provider will further enhance your ability to manage your condition and prevent potential complications. Remember, consistent and accurate monitoring, combined with professional guidance, is the key to living a healthy life with diabetes. The Ultimate Guide To The A1C Blood Sugar Connection