You may know glucose by another name: blood sugar. Glucose is key to keeping the mechanisms of the body in top working order. When our glucose levels are optimal, it often goes unnoticed. But when they stray from recommended boundaries, you’ll notice the unhealthy effect it has on normal functioning.

So what is glucose, exactly? It’s the simplest of the carbohydrates, making it a monosaccharide. This means it has one sugar. It’s not alone. Other monosaccharides include fructose, galactose, and ribose.

Along with fat, glucose is one of the body’s preferred sources of fuel in the form of carbohydrates. People get glucose from bread, fruits, vegetables, and dairy products. You need food to create the energy that helps keep you alive.

While glucose is important, like with so many things, it’s best in moderation. Glucose levels that are unhealthy or out of control can have permanent and serious effects.

Our body processes glucose multiple times a day, ideally.


Some people, however, can’t rely on their pancreas to jump in and do the work it’s supposed to do.


If the body doesn’t produce enough insulin, it can result in the release of free fatty acids from fat stores. This can lead to a condition called ketoacidosis. Ketones, waste products created when the liver breaks down fat, can be toxic in large quantities.

Testing glucose levels is especially important for people with diabetes. Most people with the condition are used to dealing with blood sugar checks as part of their daily routine.

One of the most common ways to test glucose at home involves a very simple blood test. A finger prick, usually using a small needle called a lancet, produces a drop that is put onto a test strip. The strip is put into a meter, which measures blood sugar levels. It can usually give you a reading in under 20 seconds.

Maintaining glucose levels near the normal range is an important part of keeping your body running effectively and healthily.

People who have diabetes have to pay special attention to their glucose levels. Before eating, a healthy range is 90–130 milligrams per deciliter (mg/dL). After an hour or two, it should be less than 180 mg/dL.


  • a heavy meal
  • stress
  • other illness
  • lack of physical activity
  • missed diabetes medications

In situations where your glucose level is too high, insulin will help to bring it down. For people with diabetes, too-high blood sugar is a sign that they may need to administer synthetic insulin. In less serious situations, physical activity can help lower your levels.

A glucose level is considered to be too low when it dips under 70 mg/dL. This condition is also known as hypoglycemia, and it has the potential to be very serious. Hypoglycemia can occur when people with diabetes skip their medication. It can also occur when people are eating less than normal and exercising excessively. Eating a meal or drinking juice can help to increase glucose levels. People with diabetes also often take glucose pills, which can be purchased over-the-counter at a pharmacy.

It’s possible for low blood sugar to result in a loss of consciousness. If this occurs, it’s important to seek out medical care.

Learn more: Low blood sugar (hypoglycemia) »

There are long-term consequences for unregulated glucose levels. It can lead to a variety of conditions, including:

More serious complications include diabetic ketoacidosis and hyperglycemic hyperosmolar syndrome, both conditions related to diabetes.

People who are worried that they may have diabetes should seek immediate help from a doctor.

Learn more: Diabetes tests »

As with many medical conditions, it’s easier to deal with glucose issues before they get too advanced. Healthy glucose levels are an important part of keeping a body working at its best. Eating a healthy, well-rounded diet, supplemented with exercise, is essential.

For some people, though, this isn’t enough. People with diabetes have trouble maintaining healthy and consistent glucose levels. A course of treatment can help. People with diabetes should also closely monitor their glucose levels, since the condition increases the risk of glucose-related medical issues and complications.

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