Insulin is at the heart of both types of diabetes


Dear Doctors: We keep hearing about Type 2 diabetes, and I’m embarrassed to say, I don’t actually know what it is. What does it do, and how do I know if I have it?

Dear Reader: To understand diabetes, we should first talk about glucose. That’s the sugar our bodies make from the foods that we eat, and which our cells use as their main source of fuel. Glucose travels throughout the body via the blood, which is why it’s also often referred to as blood sugar. However, it’s not immediately available to the cells. That’s where insulin, a hormone manufactured by the pancreas, comes into play. Insulin helps transport glucose from the blood into the cells, where it can be used as energy.

When someone has diabetes, it means that the insulin part of that energy equation isn’t working properly. Either the body isn’t manufacturing enough -- or any -- insulin, or it isn’t responding properly to the insulin that is present. That leads to blood-glucose levels that are too high.

Over time, high blood levels of glucose are dangerous. Adverse health effects include damage to the circulatory system, vision problems, nerve damage, stomach or intestinal problems, slow healing, kidney disease and an increase in the risk of heart disease and stroke. Extremely high blood sugar levels can lead to coma, and even death.

In Type 1 diabetes, the pancreas makes little or no insulin. It often develops early in life, but can occur at any age. This type of diabetes is managed with diet and exercise, plus the use of medications and insulin.

Type 2 diabetes, once referred to as adult-onset diabetes, often develops later in life. It occurs when the body doesn’t make or use insulin well. Type 2 diabetes often begins as insulin resistance, which is a condition in which the body stops responding properly to the insulin in the blood. This leads to a loss of the ability to control blood sugar.

Some people can manage Type 2 diabetes with diet and exercise alone. Others may also need medication or insulin to keep their blood sugar in control. Medication needs often change over time, so it’s important for everyone with diabetes to have medical care.

Elizabeth Ko, MD and Eve Glazier, MD

Symptoms of Type 2 diabetes often develop gradually. They include persistent fatigue, increased thirst and urination, blurry vision, frequent infections, slow healing and unintended weight loss. Risk factors for developing the disease include being overweight, storing excess fat mainly in the abdominal region, a family history of diabetes, inactivity and being over the age of 45. These last two factors are associated with a drop in lean muscle mass, which some researchers think may play a role.

Type 2 diabetes used to be seen most often in middle-aged adults. Unfortunately, in recent years it has increasingly been seen in young adults, adolescents and even children. If you suspect you have developed the disease, it’s important to see your doctor. Diagnosis is usually via a blood test. Treatment includes weight loss, changes to diet, exercise, blood sugar monitoring and, possibly, the use of medications or insulin.

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