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Causes of Type 2 Diabetes

Diabetes is a number of diseases that involve problems with the hormone insulin. While not everyone with type 2 diabetes is overweight, obesity and lack of physical activity are two of the most common causes of this form of diabetes. It is also responsible for nearly 95% of diabetes cases in the United States, according to the CDC. 

This article will give you a better understanding of the causes of type 2 diabetes, what happens in the body when type 2 diabetes occurs, and specific health problems that increase the risk of type 2 diabetes. Each section links to more in-depth information on that topic.

Did You Know?

Under the Affordable Care Act, many health insurance plans will cover preventive care services, including screening tests for type 2 diabetes, at no cost to you. Learn more.

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In a healthy person, the pancreas (an organ behind the stomach) releases insulin to help the body store and use the sugar from the food you eat. Diabetes happens when one of the following occurs:

  • When the pancreas does not produce any insulin.
  • When the pancreas produces very little insulin.
  • When the body does not respond appropriately to insulin, a condition called "insulin resistance."

Unlike people with type 1 diabetes, people with type 2 diabetes produce insulin; however, the insulin their pancreas secretes is either not enough or the body is unable to recognize the insulin and use it properly (insulin resistance). When there isn't enough insulin or the insulin is not used as it should be, glucose (sugar) can't get into the body's cells and builds up in the bloodstream instead. When glucose builds up in the blood instead of going into cells, it causes damage in multiple areas of the body. Also, since cells aren't getting the glucose they need, they can't function properly.

The Role of Insulin in the Cause of Type 2 Diabetes

To understand why insulin is important, it helps to know more about how the body uses food for energy. Your body is made up of millions of cells. To make energy, these cells need food in a very simple form. When you eat or drink, much of the food is broken down into a simple sugar called "glucose." Then, glucose is transported through the bloodstream to these cells where it can be used to provide the energy the body needs for daily activities. 

The amount of glucose in the bloodstream is tightly regulated by insulin and other hormones. Insulin is always being released in small amounts by the pancreas. When the amount of glucose in the blood rises to a certain level, the pancreas will release more insulin to push more glucose into the cells. This causes the glucose levels in the blood (blood glucose levels) to drop.

To keep blood glucose levels from getting too low (hypoglycemia or low blood sugar), the body signals you to eat and releases some glucose from the stores kept in the liver; it also signals the body to lower the amount of insulin being released.

People with diabetes either don't make insulin or their body's cells no longer are able to recognize insulin, leading to high blood sugars. By definition, diabetes is having a blood glucose level of greater than or equal to126 milligrams per deciliter (mg/dL) after an overnight fast (not eating anything), or by having a non-fasting glucose level greater than or equal to 200 mg/dL along with symptoms of diabetes, or a glucose level of greater than or equal to 200 mg/dL on a 2-hour glucose tolerance test, or an A1C greater than or equal to 6.5%. Diabetes must be confirmed by meeting at least two of these test criteria, or by repeating one of these tests on a different day.

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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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