Blood Sugar Testing: Your Guide to Control

Ever wondered why blood sugar testing is so vital for diabetes care? Monitoring glucose levels fuels better control of the condition. It supports a healthier life by preventing complications. In this guide, learn how to test your blood sugar, when to do it, and why it matters so much for your well-being.

Importance of Testing

Blood sugar testing is a crucial part of daily diabetes management. It helps you see how medicines, diet and exercise impact your glucose. With testing glucose levels, you can spot highs or lows in time to take action. That could mean adjusting medicines or eating fast-acting carbs. This ongoing tracking helps you pursue and reach your treatment goals.

Why test blood sugar

Monitor how diabetes medicine affects glucose levels.
Adjust insulin doses after checking with your care team.
Respond quickly to signs of high or low blood sugar.
See progress toward treatment targets.
Learn how meals and workouts change your levels.
Notice the impact of stress or sickness on your numbers.

When to Test

Your healthcare team can guide you on frequency. It depends on the type of diabetes and the treatments you use.

Type 1 diabetes

A continuous glucose monitor (CGM) may be suggested. Or blood sugar checks might happen 4 to 10 times a day. Possible times include:

Before meals, snacks and sometimes after meals.
Before and after exercise.
At bedtime.
During the night in some cases.
After treating low blood sugar.
More often when sick.
If you change your daily routine.
When starting new medicine.

Type 2 diabetes

If you take insulin, a CGM or frequent blood sugar checks may be needed. You might test before meals and at bedtime if you use multiple insulin shots. Intermediate- or long-acting insulin might require fewer checks. You may need more glucose monitoring if you:

Feel sick.
Plan to drive long distances.
Change your diet or exercise plan.

You might not test every day if you manage type 2 diabetes with only diet, exercise or non-insulin medicines.

Continuous Glucose Monitors (CGMs)

Continuous glucose monitor and insulin pump
A CGM reads blood sugar every few minutes using a device on your skin and a sensor under the skin. These sensors often last 10 days to two weeks, though some implanted sensors can last six months. CGMs send data wirelessly to a receiver, smartphone or insulin pump.

Some CGMs show glucose levels at all times and include alarms for sudden spikes or drops. Others need scans every few hours. You may still need a blood sugar meter for calibration or to confirm readings.

Certain factors, such as wine or specific medicines, may affect older CGMs. Medications like acetaminophen, aspirin and vitamin C can alter readings. Newer CGMs show fewer issues if doses are moderate. Check your device’s guidelines or consult a professional if you take these medicines.

These monitors might be less reliable if you’re pregnant, have kidney problems, or feel very ill.

Know Your Target Range

Ask your healthcare provider for your ideal testing glucose levels. Factors include:

Type of diabetes.
Your age.
Pregnancy status.
Other medical conditions.
How long you’ve had diabetes.
Overall health.

For many healthy adults with diabetes, the American Diabetes Association (ADA) suggests:

80-130 mg/dL (4.4-7.2 mmol/L) before meals
Under 180 mg/dL (10.0 mmol/L) two hours after meals

These goals may vary. Mention consistent high or low readings to your healthcare team.

How to Test Blood Sugar

A blood sugar meter measures glucose in a small blood sample, often from your fingertip. Insert a test strip, prick your fingertip with a lancet, then apply the drop of blood to the strip. The meter shows your glucose result after several seconds.

Some meters allow testing from other sites, like the forearm, but readings can be less precise if you’ve recently eaten or exercised. For certain CGMs, daily calibration is still required using a standard meter.

Record Your Results

Decide with your provider how often to log readings. Most devices can send data to a computer or smartphone. If logging manually, note the date, time, result, medicine doses, diet and activity. Bring your record to checkups. If your numbers often fall outside targets, ask for guidance.

Meter Care Tips

Follow the user manual carefully.
Use the recommended drop size of blood.
Only use strips made for your meter.
Store strips correctly. Don’t use them past expiry.
Clean the meter and run checks as advised.
Take the meter to your appointments to confirm correct use.

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