Blood sugar basics

What should your blood sugar levels be?

Once diagnosed with diabetes, your health care team will review your "target" blood sugar levels with you. You will likely be told to start checking your blood sugars at home using a meter. Normal blood sugar levels (i.e., people who have not been diagnosed with diabetes) are usually between 4.0 mmol/L and 8.0 mmol/L. If your blood sugars are at levels recommended by your physician or primary health care provider, then it is said that your blood sugars are "in control."

For people with either type 1 or type 2 diabetes, the recommended target blood glucose levels are:

• 4.0 mmol/L to 7.0 mmol/L when measuring blood glucose fasting or before eating
• 5.0 mmol/L to 10.0 mmol/L when measuring blood glucose 2 hours after eating (your physician or primary health care provider may recommend a range of 5.0 mmol/L to 8.0 mmol/L if you are not at your A1C target - see below)

These are general recommendations - your health care provider may suggest different targets for you. In addition, pregnant women, the elderly, and children 12 years old and younger may have different targets.

What is urine testing?

Before the advent of home blood glucose monitors, the only way to monitor or check for high sugar levels was by urine testing. When blood sugar levels get high enough, the kidneys excrete the excess glucose into the urine. This is important, because if your blood sugar levels are high enough that the sugar "spills" into the urine, they are very high.

While urine testing is no longer used to monitor blood sugar levels, it is still used to measure ketone levels (high levels are a sign of poor diabetes control) and albumin levels (a protein that, if found to be at high levels in the urine, could be a sign of kidney damage).

What is a hemoglobin A1c test?

The hemoglobin A1C (HbA1C) is an accurate way to measure how well your diabetes is being controlled. It provides a measurement of the average glucose level in your blood over the last 3 to 6 months; an average measurement means this test does not show daily fluctuations. When blood sugars are consistently high over time, the HbA1C will also be high.

When HbA1C is high, you will need to make changes to your medication or lifestyle (e.g., more exercise or introducing a healthier diet).

The recommended target in Ontario for most people with diabetes is an HbA1C of less than or equal to 7.0%. A1C levels should be measured at least every 6 months.