People with diabetes work to keep their blood sugar (glucose) as near to normal as possible. Keeping your blood glucose in your target range can help prevent or delay the start of diabetes complications such as nerve, eye, kidney, and blood vessel damage.

When you learned you had diabetes, you and your health care team worked out a diabetes care plan. The plan aims to balance the foods you eat with your exercise and, possibly, diabetes pills or insulin. You can do two types of checks to help keep track of how your plan is working. These are blood glucose checks and urine ketone checks.

Blood Glucose Monitoring Checks

Blood glucose monitoring is the main tool you have to check your diabetes control. This check tells you your blood glucose level at any one time. Keeping a log of your results is vital. When you bring this record to your health care provider, you have a good picture of your body's response to your diabetes care plan. Blood glucose checks let you see what works and what doesn't. This allows you and your doctor, dietitian, or nurse educator to make needed changes.

Here is a table that lists blood glucose ranges for adults with diabetes:

 

Glycemic control
A1C	<7.0%
Preprandial plasma glucose (before a meal)	70–130 mg/dl (5.0–7.2 mmol/l)
Postprandial plasma glucose (after a meal)	<180 mg/dl (<10.0 mmol/l)
Blood pressure	<130/80 mmHg

How Blood Checks Work

You stick your finger with a special needle, called a lancet, to get a drop of blood. With some meters, you can also use your forearm, thigh or fleshy part of your hand. There are spring-loaded lancing devices that make sticking yourself less painful. Before using the lancing device, wash your hands or site you chose with soap and water. If you use your fingertip, stick the side of your fingertip by your fingernail to avoid having sore spots on the frequently used part of your finger.

Checking With a Blood Glucose Meter

Blood glucose meters are small computerized machines that "read" your blood glucose. In all types of meters, your blood glucose level shows up as a number on a screen (like that on your pocket calculator). Be sure your doctor or nurse educator shows you the correct way to use your meter. With all the advances in blood glucose meters, use of a meter is better than visual checking.

How to Pick a Meter

There are many meters to choose from. Some meters are made for those with poor eyesight. Others come with memory so you can store your results in the meter itself. The American Diabetes Association does not endorse any products or recommend one meter over another. If you plan to buy a meter, here are some questions to think about:

• What meter does your doctor or diabetes educator suggest? They may have meters that they use often and know best.
  
   
• What will it cost? Some insurance companies will only pay for a certain meter. Call your insurance company before you purchase a meter and ask how to get a meter and supplies. If your insurance company does not pay for blood glucose checking supplies, rebates are often available toward the purchase of your meter. You still have to consider the cost of the matching strips and lancets. Shop around.
  
   
• How easy is the meter to use? Methods vary. Some have fewer steps than others.
  
   
• How simple is the meter to maintain? Is it easy to clean? How is the meter calibrated (set correctly for the batch of strips you are using)?

 

Are meters accurate?

Experts testing meters in the lab setting found them accurate and precise. That's the good news. The bad: meter mistakes most often come from the person doing the blood checks. For good results you need to do each step correctly. Here are other things that can cause your meter to give a poor reading:

• a dirty meter
   
• a meter or strip that's not at room temperature
   
• an outdated test strip
   
• a meter not calibrated (set up for) the current box of test strips
   
• a blood drop that is too small

Ask your health care team to check your skills at least once a year. Error can creep in over time.

Logging Your Results

When you finish the blood glucose check, write down your results and use them to see how food, activity and stress affect your blood glucose. Take a close look at your blood glucose record to see if your level is too high or too low several days in a row at about the same time. If the same thing keeps happening, it might be time to change your plan. Work with your doctor or diabetes educator to learn what your results mean for you. This takes time. Ask your doctor or nurse if you should report results out of a certain range at once by phone.

Keep in mind that blood glucose results often trigger strong feelings. Blood glucose numbers can leave you upset, confused, frustrated, angry, or down. It's easy to use the numbers to judge yourself. Remind yourself that your blood glucose level is a way to track how well your diabetes care plan is working. It is not a judgment of you as a person. The results may show you need a change in your diabetes plan.