Making the Most of Your Blood Glucose Readings
The Numbers Game
By Paige Reddan, M.S., R.D., C.D.E.
Bob recently went back to see his doctor and came away with good and bad news. The bad news was that his A1C (a number that represents blood glucose control during the past three months) had gone up. The good news was that his doctor suggested a solution. He said if Bob began testing around meals, he might begin to see the connection between his food choices and his overall blood-glucose control. Then he could take steps to improve his A1C. The American Diabetes Association recommends an A1C value of less than 7 percent.
Fasting blood glucose tells you where you start the day
Many people with diabetes are taught the mechanics of using a meter and how to record blood glucose results. However, not as many people know the value of the test result flashing up on the screen. It is the job of the diabetes educator to explain to their patients with diabetes why and how to test blood glucose. In addition, they should help them find ways to make blood glucose testing a habit and to identify barriers that may prevent them from testing.
A fasting blood glucose reading can tell you a number of things. Glucose released from the liver occurs primarily at night while you sleep. Thus, the action of the liver can result in a higher fasting glucose. Often, people think dinner was the culprit when, in fact, it was the liver. Your doctor might recommend a medication to slow the liver’s output of glucose, or suggest exercise.
Your fasting result may also reflect the exercise you did the day before. Ever notice that the day after a 30-minute walk, you have a better fasting reading? This is because glycogen stores in the liver and muscle need to be replenished following each bout of exercise. This results in increased glucose uptake until the glycogen stores are replaced—a process that can take 24 to 48 hours.
After-meal blood glucose tells you about your food choices
For most people, blood glucose should be less than 140 mg/dL two hours after a meal. Testing after meals can be useful in identifying how food portions affect blood glucose control.
Low blood glucose tells you to take action now
It’s normal for blood glucose to go up and down throughout the day. A low blood glucose (hypoglycemia) is telling you something important. It is caused by not enough glucose for the exercise you are doing. Symptoms of hypoglycemia include:
- Hunger
- Shakiness
- Perspiration
- Dizziness
- Sleepiness
- Confusion
- Difficulty speaking
- Feeling anxious or weak
Make sure you discuss frequent hypoglycemic episodes with your doctor. Like Bob, you might also want to consider talking to your doctor about testing around meals. It could help you to be in control of your diabetes, your blood glucose and your food choices.