Estimated Average Glucose Normal Range – What is It?

Achieving In Range Blood Glucose Levels

By Susan B. Sloane, BS, RPh, CDE

As those with diabetes know achieving in-range blood glucose levels can be a bit of a roller coaster ride.  Without any insulin production by the body, a Type 1 patient must rely on insulin injections to keep blood sugars in between the navigational beacons. Depending where people with Type 2 diabetes are holding, they too need to keep tabs on their blood sugar levels.

Keeping blood sugars within these parameters is challenging, but with knowledge and patience, quite achievable. Each person with diabetes will have a target blood glucose that they want to achieve at any given time of day. Self-monitoring of blood sugars is an essential component of diabetes care. ¹ These targets are generally given to a patient by their health care team and will often indicate a range of acceptable blood glucose levels.

The average blood glucose range that is considered to be a good range to aim for is 80-130 mg/dl (4.4-7.2 mmol/L), according to the American Diabetes Association’s Standards of Care^.2 Although there is no hard-and-fast number, and other recommendations do exist. For example, the Dario™ Blood Glucose Monitoring System app comes preset with 80-120 mg/dl (4.4-6.7 mmol/L) as the in-range value; however, this can and should be changed based on individual needs and consultation with your healthcare provider.  Blood glucose levels should generally be at the lowest point first thing in the morning, which is known as a fasting blood glucose.

There are several points during the day that blood glucose should be measured, and the number of readings you need to achieve the best diabetes control will be determined by your own health care team.  Each reading you get will tell you how well your insulin is working and help you make important decisions concerning insulin dosing and meal planning.  As a rule, morning blood glucose levels will tell you how well your basal or background (long-acting) insulin is working.  If your fasting blood sugar is running over your target blood glucose for a few days in a row, your health care team may suggest an increase in your basal insulin.  The key with analyzing any blood glucose value is to establish a pattern by charting your values.  The Dario smart diabetes management solution can assist you in storing and letting you get a good visual picture of your blood glucose readings with its logbooks, charts and statistics.  The native smart phone app and website portal are also fully equipped with a “share” feature, to allow you to share your information with healthcare practitioners and any caregivers that will be helping you find solutions to potential roadblocks, and to help cheer you on as you make good progress.

Other meaningful readings of blood glucose values are the before meal reading, which will assist you in making the decision of how much insulin to give for a given meal.  The insulin dose before a meal will generally depend on how much food, or by definition, how many carbohydrates you are going to consume at a given meal. This is known as a bolus or rapid acting dose of insulin.  This dose is calculated by an insulin to carbohydrate ratio, which is basically how many units of insulin it will take to bring your blood sugar within your target range.  One example of how a starting bolus dose is calculated is by dividing 500 by your total daily insulin dose.  This will give you a starting point of how many carbohydrates are covered by 1 unit of rapid acting insulin such as insulin aspart, lispro, or glulisine.   Different medical practices use this formula as a starting point, but others use other methods as well.

If your blood glucose is higher than your target before a meal, you may need additional insulin in addition to the insulin that normally covers your meal to correct for this.  Conversely, if you have a low blood glucose reading before a meal, you will possibly need to eat more or take less insulin for a given meal.    There are an array of variables that affect blood sugars beyond just carbohydrate intake.

Exercise during the day, for example, can bring blood sugars down lower than expected for up to 48 hours after exercising.³ Alcohol is another important variable that can cause a drop in blood glucose for several hours after drinking, depending on how much alcohol is consumed.³  It is important to take these components into consideration when making decisions on insulin dosing and food consumption.

Testing blood sugars one-and-a-half to two hours after a meal will give you important information as to whether the insulin dose used before the meal was adequate or perhaps too much.  According to the American Diabetes Association, a good post-meal blood sugar target is 180 mg/dl (10.0 mmol/L) or below.² Your health care provider may give you personalized goals that may be a bit different.  Not every patient always has the same target values. We will discuss the reasons for this variation in target values between patients in future installments of these articles.

It is not possible to test blood sugars at every point in time, which is why we pick at some key times/instances when blood sugar testing is recommended.  It is for example, critical to test blood sugar levels before performing tasks that require long periods of concentration, such as before taking an exam or before driving a vehicle.  Testing blood sugars before exercise is also very important, as exercise causes blood sugars to drop.  It is possible to record exercise days and even sick days (which cause blood sugars to go up higher than normal), within the cloud using your Dario meter.  All this information is critical to establishing how your own body reacts to certain conditions, and how best to dose insulin and manage a meal plan.

If your head is spinning, don’t worry.  Over time the balancing act becomes second nature.  I can say this, having raised two sons with Type 1 diabetes myself.