How Blood Glucose Works
Glucose is a type of sugar in the blood that provides energy to the cells in your body. When you eat, the amount of glucose in your blood rises and then drops again as your body releases insulin to help move the sugar from your bloodstream into your cells. If too much time passes before eating again, the liver steps in and releases stored glucose to counteract drops in blood sugar. The underlying goal is to always keep your blood glucose level stable within the normal range.
Normal Blood Glucose Levels
Your ideal blood glucose level depends on several factors, including your age, life expectancy and medical history. If you do not have any form of diabetes, your normal fasting blood sugar level should range from 80-99 mg/dL, with a potential increase up to 140 mg/dL right after eating. If you have been diagnosed with diabetes, your acceptable fasting blood sugar level could be higher at 80-130 mg/dL, with a possible spike up to 180 mg/dL after eating.
Diabetes and Blood Glucose
In some cases, the pancreas doesn’t effectively accomplish its job. Individuals who have diabetes either don't produce any insulin at all — or produce very little — or are resistant to the effects of insulin. If insulin isn’t released into the bloodstream or doesn’t properly do its job, glucose from the foods we eat simply builds up in the bloodstream instead of turning into energy, resulting in diabetes.
Those who develop the most severe forms of diabetes require insulin replacement therapy to control the level of glucose in their blood. In less severe cases, dietary changes and exercise help with diabetes management, although medications and insulin may also be necessary for effective control.
If you develop diabetes, you will need to check your blood glucose level several times a day, usually before and after you eat. This helps you determine how many carbohydrates you can consume in each meal and how much medication or insulin you need to take. The most common way to check your blood sugar level at home is with a glucose meter. These devices allow you to place a small drop of blood on a test strip that slides into the meter. It then analyzes the drop of blood and reports the blood glucose level on the display.
Symptoms and Complications of High Blood Glucose Levels
Hyperglycemia is the medical term for a temporary high blood glucose level in someone with diabetes. This can happen if you eat too much, skip a dose of insulin or your oral diabetes medication, or develop an infection. A high blood sugar level can have serious consequences if you have diabetes, particularly Type 1 diabetes. If your blood sugar isn’t lowered, it could lead to diabetic ketoacidosis, a life-threatening condition that could result in a coma. Symptoms of high blood sugar include frequent urination, excessive thirst, frequent infections, blurred vision, irritability and fatigue.
Hypoglycemia and Blood Glucose
Hypoglycemia is the medical term for temporary low blood sugar, although it can sometimes develop into a chronic condition. It can occur for several reasons, but it happens most often in those with diabetes. In some cases, hypoglycemia is actually a side effect of something else, such as certain liver and kidney diseases, hormone deficiencies and certain medications. In general, a blood glucose reading that is lower than 70 mg/dL puts you at risk of experiencing a hypoglycemic episode.