Blood Glucose Tests.
The first test we need to deal with is one we have to do ourselves, every single day. This is the monitoring of our own blood glucose (BG) levels.
The equipment needed is a blood glucose meter (glucometer), appropriate test strips and a lancet device (something with a point that will prick your finger).
Meters do vary between manufacturers so you will need to read the manual that comes with yours to get accurately test results, if you have not already been taught how by your diabetes advisor.
However there is some general advice applicable to all users:-
1. First wash your hands with soap and warm water, rinse them well and dry them on a clean cloth.
2. Insert the test strip into the meter.
3. Prick your chosen finger with the lancet. Pricking the side of the finger hurts less than the end. Having warm hands and holding them below the level of the heart encourages the blood flow.
4. Once a small drop of blood appears catch it with the test strip.
The result of your test will appear on the digital display. Keep a record of the result. Note that in America the results are measured in milligrams per decilitre (mg/dL) while in the UK and elsewhere the measurement of millimoles per litre is used.
If this is confusing you then conversion information is available on this site at our Diabetic Test Conversions page,
and off site at,
Joslin Centre Conversion Table.
The reason we do these tests.
We need to keep our blood glucose levels within safe perimeters for the sake of our health. This is the only way we can find out what they are and what things affect them.
Without this knowledge we could go along blissfully ignorant of the fact that the food we felt was safe was actually sending our BG soaring and putting us at risk of serious complications.
When should you do these tests?
Until you understand your diabetes and how certain foods work for you it is a good idea to test frequently. The initial test should be done when you first get up. This is called a 'fasting test' and gives you a starting point for the day.
The next test is taken 2 hours after you have had a meal, called a '2-hour postprandial test'. This tells you how high your BG goes when you eat those particular foods.
The third test is just before the next meal and tells you whether your BG has returned to the starting point since your last meal.
Then you can choose to test after that meal, before you go to bed, before and after you exercise and in fact at any time when you feel you would like to know what is happening to your BG. These are referred to as random blood sugar tests.
Non-diabetics BG does not vary much throughout the day so if your BG shows violent swings it is an indicator of a problem.
What should the BG levels be?
There is a certain amount of disagreement amongst experts here. Your doctor will work out what your range should be, taking into consideration your age, any complications, other medical conditions etc.
The ADA (American Diabetes Association) recommends a blood glucose range of
80 to 120 mg/dl (4.4 - 6.7mmol/l) before meals and
100 to 140 mg/dl (5.6-7.8mmol/l)at bedtime.
In the UK the levels are given as
4 to 7mmol/l (72-126mg/dL) before meals.
Less than 10mmol/l (180mg/dL) two hours after a meal
Around 8mmol/l (144mg/dL) at bedtime.
There are others who feel these ranges are far too high and we should endeavour to keep our BG levels between 4,4 and 5mmol/l (80 - 90mg/dL) permanently.
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