How Glucose Is Produced
As our body digests foods, it breaks down the carbohydrates, separating glucose from other important nutrients. The nutrients are then absorbed by the small intestine and circulated throughout the body. Glucose, however, needs a helping hand before the body can use it—it needs insulin. Insulin is a hormone produced by the pancreas; it expedites the transport of glucose through the body into the cells. It also guides the liver to store excess energy as glycogen (short-term storage) or triglycerides in fat cells.
Blood glucose rates naturally rise slightly right after a meal. Insulin is released into the blood by the pancreas in response to this rise in blood glucose. The glucose moves into the cells where it is metabolized by the body. The blood glucose level then begins to fall, and the pancreas slows its response and eventually stops releasing insulin.
What Glucose Has to do with Diabetes
The most common condition that causes high or low blood glucose is diabetes. A person with diabetes cannot produce adequate insulin or is insulin resistant (meaning the body is still capable of producing insulin, but the insulin is no longer effective at reducing blood glucose). Individuals with diabetes are often unable to process and use glucose without the assistance of medication, shots, or other treatment options.
People who cannot produce enough insulin to process glucose have type 1 diabetes. People whose bodies are resistant to insulin, or who cannot produce enough insulin due to pancreatic islet cell “exhaustion,” have type 2 diabetes.
When to Check Blood Glucose Levels
For the most useful information, check your blood sugar immediately before meals and before going to sleep for the night. Keep a journal or notebook with the date and time and the glucose number. Also, be sure to make note of anything that might be important to a reading—if you had been without food for an unusually long time, if you had a snack between meals that might increase your blood sugar, etc. Bring this notebook to doctors’ appointments so you can review it and make changes to your treatment if necessary.
What is Tested
A simple blood test measures the amount of glucose in your blood, and a urine test measures glucose in your urine. Glucose, the primary energy source for the body’s cells, is also the only source of energy for the brain and nervous system. Therefore, keeping a steady supply is vital to your body’s proper function and control.
How to Check
A blood sample is required to check blood glucose levels. The most common type of blood glucose monitor requires using a lancet to prick the end of your finger to draw a small drop of blood. This drop is then placed on a disposable testing strip that is inserted into an electronic blood glucose meter. The meter measures the level of glucose in the sample and returns a number on a digital readout.
Some diabetics may use a continuous glucose monitor—a small wire inserted beneath the skin of the abdomen that measures blood glucose levels every five minutes and delivers the results to a monitor device worn on the person’s clothing or in a pocket. This allows the patient and doctor to keep a real-time reading of blood glucose levels.
Recommended Blood Sugar Targets
Blood glucose numbers are measured in milligrams per deciliter (mg/dL).
The American Diabetes Association recommends the following blood glucose targets for people with type 2 diabetes:
From 70 – 130 for adults
One to two hours after eating a meal
Less than 180 for adults
Glucose is normally found in urine in either low or undetectable amounts. If you perform a urine glucose test and the results show more than 15 mg/dL, you should test your blood glucose levels, or call a health care professional.