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Diabetes Health Center

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Causes of Type 2 Diabetes

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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.

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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.

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