Measuring sugar levels in blood and urine yourself

Photo of blood sugar measurement (PantherMedia / pasiphae)

Many people with diabetes measure their blood sugar levels on their own. For those who inject insulin several times a day, checking their sugar levels with a blood glucose meter is an important part of their daily treatment.

The amount of insulin that is injected at mealtimes depends on various factors, including the measured blood sugar level. Sugar levels in blood or urine can be measured in various ways. Sugar levels can also be measured in body tissue.

Measuring blood sugar levels yourself

You can measure your blood sugar levels yourself using an electronic device called a blood glucose meter. To do this, you prick your fingertip with a small needle, and place a drop of blood on a test strip. The strip is inserted into the blood glucose meter. The digital display shows your blood sugar level shortly afterwards. This is how the blood glucose meter is used:

  • First of all, lay out everything you need: a blood glucose meter, a blood-sampling device with a fine needle (lancet), and a test strip.
  • Wash your hands before measuring your blood sugar because dirt and other residues can mix with the blood and distort the results.
  • Take a test strip out of the package and insert it into the glucose meter.
  • One small drop of blood is enough for the test. It should just fill the test field. If you prick the side of your finger rather than your fingertip, you feel it less. You can get the right amount of blood by gently squeezing the tip of your finger.
  • Then carefully place the drop of blood on the test strip without smearing it.
  • After a short while your blood sugar level will be displayed on the meter. Modern devices can save the measurements along with the date and time, and transfer this information to a computer or smartphone. If this is not possible, you could write the measurements down in a special diary.

If you measure your blood sugar levels frequently, pricking yourself is less uncomfortable if you use a different finger, or a different place on your finger, each time.

It can be helpful to read up about the different available glucose meters and how to use them before getting a new one. It is important to be able to manage the device easily in everyday situations.

What does the result mean?

Slight fluctuations in blood sugar levels are completely normal and also happen on a daily basis in people who do not have diabetes. Blood sugar levels are influenced by things like what – and how much – we eat and drink, how much we exercise, and what medications we take. Depending on whether blood sugar levels are measured on an empty stomach or after a meal, they vary between 3.3 and 7.8 mmol/L (about 60 and 140 mg/dL) in healthy people. There are no clear-cut boundaries between the normal range of blood sugar and high or low blood sugar.

Illustration: Normal range of blood sugar between hyperglycemia and hypoglycemiaBlood sugar: Normal range between hyperglycemia and hypoglycemia

Measuring sugar in your urine yourself

You can also measure your sugar levels in your urine on your own. Having sugar in your urine is usually a sign of very high blood sugar levels. The extra sugar in the bloodstream is usually only removed via the kidneys and detectable in urine at blood sugar concentrations of 10 mmol/L (180 mg/dL) and above. In order to measure the amount of sugar in your urine, you need a urine test strip (dipstick) and a container for collecting urine.

It is important to talk with your doctor about the best time of day to do the urine test, and whether to do it before or after eating. When measuring sugar in your urine yourself, you need a sample of urine that has not been in your bladder for long. So an early-morning urine sample isn’t suitable because it has collected in your bladder overnight. Instead, it is more typical to urinate and collect a sample about an hour after the last time you went to the toilet. The test strip is then dipped into the sample. After about two minutes the color pads on the test strip show the results.

What does the result mean?

To find out what the results mean, the colors on the test strip are compared with the color chart on the package. If the colors on the test strip do not change, you do not have sugar in your urine. The more the color changes, the more sugar there is in your urine, and therefore in your blood. But it is not possible to find out exact blood sugar levels using urine tests. They can only determine whether you have very high blood sugar. This is because the body doesn’t generally get rid of sugar in urine if someone’s blood sugar levels are normal or low.

Measuring blood sugar levels in a laboratory

Blood sugar levels can be measured a lot more accurately by taking a blood sample from a vein and having it tested in a laboratory. Blood sugar is sometimes measured as part of a routine blood test in the hospital or at the doctor’s. A special kind of test called a glucose tolerance test also involves taking blood samples – in this case, to see how the body deals with larger amounts of sugar.

Most people with diabetes have the HbA1c levels in their blood measured regularly. Your HbA1c value is a measure of how high your blood sugar levels have been on average over the last eight to twelve weeks. This is an indication of how well-controlled your blood sugar is and whether your diabetes treatment might need to be adjusted.

 

Additional option for monitoring glucose levels

Devices that measure the amount of sugar in fat tissue underneath your skin offer another way to continuously monitor sugar levels. This is called continuous glucose monitoring (CGM). CGM devices measure the amount of sugar in the fat tissue every few minutes, and alert you if the levels are too high or too low. CGM devices are also available in combination with an insulin pump.

People who have type 1 diabetes can improve the regulation of their blood sugar levels by monitoring the sugar levels in their tissue.

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