How Insulin and Glucagon Work
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How Insulin and Glucagon Work

Balancing Act

Insulin and glucagon are hormones that help regulate levels of blood sugar (glucose) in your body. Glucose, which comes from the food you eat, is important to fueling your body. Insulin and glucagon are equally important in managing blood glucose, making sure your body functions well.

Insulin and glucagon are like the yin and yang of blood glucose maintenance. These hormones partner to balance your blood sugar, keeping your levels in the narrow range required by your body. When you eat, your pancreas releases insulin to help lower blood sugar; between meals, your pancreas releases glucagon to help keep blood sugar levels steady. 

If you have diabetes or prediabetes, your body either can’t use the insulin you make properly, doesn’t produce enough insulin or doesn’t produce insulin at all. In turn, this causes an improper amount of glucagon to be released. When the system is thrown out of balance, it can lead to dangerous levels of glucose in your blood.

How Insulin Works

Insulin is a vital hormone produced by cells in your pancreas. Insulin works to move glucose from the blood and into cells for energy or storage for later energy.

During digestion, foods that contain carbohydrates are digested and converted to glucose. This causes a rise in blood glucose. The increase in sugar signals your pancreas to produce the amount of insulin you need to manage the level of sugar in your blood.

When insulin is produced, glucagon is suppressed. Insulin stimulates the cells throughout your body to take in glucose from your bloodstream. Your cells then use glucose as energy.

In order to help fuel the body between meals, excess glucose is stored in cells of the liver and muscles as glycogen. As glucose is converted to energy or stored in the liver and muscles, its levels in your blood are reduced.

How Glucagon Works

Like insulin, glucagon is a protein hormone produced in the pancreas. It is a counterbalance to insulin.

Approximately four to six hours after you eat, the glucose levels in your blood become reduced. This triggers the production of glucagon in the pancreas. When the pancreas secretes glucagon, it suppresses insulin. 

Glucagon signals the liver and muscles to break down glycogen into glucose and release glucose back into your bloodstream. This keeps your blood sugar levels from dipping too low.

How Much Glucose Is Normally Found in Blood?

The National Institutes of Health provides the following guidelines for blood glucose levels.

Normal blood glucose levels in people who do not have diabetes are:

  • fasting: 70 to 99 milligram/deciliter (mg/dL) 
  • after meals: 70 to 120 mg/dL

Target blood glucose levels in people who do have diabetes are:

  • before meals: 70 to 110-130 mg/dL
  • one to two hours after the start of a meal: below 180 mg/dL           


The regulation of blood glucose in the body is an amazing metabolic feat. It often doesn’t work as designed, however. Diabetes mellitus, the most well known condition in which blood sugar balance goes awry, affects 29.1 million Americans, according to the Centers for Disease Control and Prevention. Diabetes refers to a group of diseases.

Type 1 Diabetes

Type 1 diabetes is the less common form of diabetes. It is possibly an autoimmune disorder in which your immune system destroys the cells in your pancreas that make insulin. Previously referred to as “insulin-dependent diabetes,” people with type 1 diabetes must take insulin to stay alive.

Type 2 Diabetes

Type 2 diabetes occurs when your cells don’t respond to insulin. Over time, your body reduces the production of insulin and blood sugar levels go up.

Strongly linked to obesity, type 2 diabetes accounts for 90 percent to 95 percent of all diagnosed cases of diabetes, according to the National Diabetes Information Clearinghouse. Type 2 diabetes can be controlled with medications and lifestyle changes, such as weight loss, good nutrition, and exercise.

Gestational Diabetes

Some women acquire gestational diabetes late in their pregnancy. In this condition, it’s believed that pregnancy-related hormones interfere with the function of insulin. Gestational diabetes normally disappears after the pregnancy ends, but women who have had the condition are at greater risk of developing type2 diabetes in the future.


If you have prediabetes, your body makes insulin but doesn’t use it properly. As a result, your blood glucose levels are elevated, but not high enough to fit in the classification of type 2 diabetes. Many people who have prediabetes do progress to type 2 diabetes. But with lifestyle changes, including weight management, exercise, and a healthful diet, type 2 diabetes can be staved off.

Healthy Living

Not all forms of diabetes can be prevented. However, maintaining a healthy lifestyle, including exercise and a healthy diet, can prevent or delay prediabetes and type 2 diabetes.

Healthy living is also important to living well with any form of insulin-related disease. Getting plenty of exercise and being conscious about your diet are important tools in managing conditions caused by diabetes.