But what exactly is Diabetes? There are a lot of myths and misunderstandings surrounding the disease, particularly when it comes to type 1 versus type 2.
So let’s start with the basics. Diabetes is a chronic condition characterized by high blood glucose (sugar), but it’s really all about a hormone called insulin. Depending on the type of diabetes you have, your body either can’t make enough insulin to keep blood sugar levels down (type 1), or can’t effectively use the little insulin that it does produce (type 2).
First, to understand what happens in the bodies of people who have diabetes, you should know what happens in the bodies of people who don’t.
Blood sugar, or glucose, is the body’s main source of energy. This glucose comes from food—mostly carbohydrates, but occasionally from proteins, too.
In a healthy body, carbs are all broken down into glucose. That glucose leaves the intestine, travels through the liver, and eventually makes its way into the blood stream. Its final destination is the body’s cells, where it is used to create energy.
Insulin comes into play here, at the cells’ entrance. The hormone acts as a doorman, allowing glucose to come inside.
Insulin is produced in the pancreas by little clusters of cells, known as beta cells. Beta cells sense when there is an excess of glucose in the blood stream, such as just after a meal, and they send insulin out to meet the glucose at the cell’s doors.
When working properly, this interplay between glucose, insulin, and beta cells maintains glucose levels between 70 and 140 milligrams per deciliter of blood.
In both types of diabetes, this balance gets interrupted in some way.
In type 1, the body’s immune system starts attacking and destroying parts of itself—specifically, its own beta cells. Fewer beta cells means less insulin secreted into the body. And less insulin means that glucose is locked out of cells, and stays in the blood stream.
As type 1 diabetes progresses, it’s thought that beta cells are completely wiped out (though some early research suggests there may still be some faint activity of beta cells in some people with type 1).
Most people with type 1 diabetes need to start injecting insulin as soon as they are diagnosed. They do need to be careful of what they eat, so to avoid causing spikes in their blood glucose, but type 1 cannot be controlled solely with diet. The necessity for treatment with insulin is why type 1 is classified as insulin-dependent.
In type 2, some insulin is released but the locks on the cells are damaged. Insulin’s keys no longer fit, and the cells refuse to unlock. Because the door isn’t opened, glucose can’t enter, also resulting in heightened blood glucose levels. This is called insulin resistance—since the cells are resistant to the influences of insulin.
Genetics certainly affect susceptibility to insulin resistance, but another major factor is obesity. The greater your BMI, the harder your body has to work to make insulin effective. So it’s no coincidence that the global epidemic of type 2 diabetes coincides with rising rates of obesity.
In early stages, it’s possible to control type 2 with diet and exercise. Losing just 7 to 10 percent of your body weight can make the insulin your body produces more effective; meal planning helps you eat according to the amount of insulin available in your body, and exercise helps to increase insulin sensitivity (though many institutions recommend that patients get help from a medicine like metformin right away).
And for a while the body can overcome the cells’ resistance. But over the course of type 2, particularly when it’s poorly managed, the body stops being able to make enough insulin to force its way into the cells. When this happens, people with type 2 also need to start insulin injections.
Type 1 and type 2 are different in their root causes, but the effects are eventually the same. Problems with insulin interrupt the finely honed system and glucose in the blood rises, which, if left untreated, may result in complications like nerve and eye damage.
These are just the very basics of the two major types of diabetes—there is a lot to know about the disease and its variations. But understanding your body is the first step.
For more information on living with diabetes, visit the Joslin web site.