What’s The Difference Between Type 1 and Type 2 Diabetes?

There are two main types of diabetes: type 1 and type 2. Both types of diabetes are chronic and characterized by excess levels of blood glucose (sugar).

Type 2 diabetes is the most common type, representing 90 to 95 percent of all cases, while type 1 diabetes represents approximately five percent of all cases. It is estimated that more than 100 million American adults are living with diabetes or prediabetes.

What causes diabetes?

Glucose is the main source of energy for your body. It enters your cells with the “key” that is insulin. Insulin is a hormone produced by your pancreas, which is located in your abdomen just behind the stomach.

If your pancreas can’t keep up with the demand for insulin or if your body becomes resistant to the actions of insulin, your blood sugar levels will skyrocket, leading to diabetes.

Causes of type 1 diabetes

Type 1 diabetes (insulin-dependent diabetes) is characterized by a lack of insulin production by the pancreas; think of it as not having a key. The lack of insulin leads to high blood sugar levels and eventually diabetes.

Type 1 diabetes is commonly classified as an autoimmune disease, but it can be idiopathic (meaning its cause is unknown). Autoimmune refers to the fact that your body mistakenly attacks its own tissues, and in this case specifically, the cells of the pancreas that produce insulin. Markers of autoimmunity (e.g., autoantibodies against islet cells, insulin, glutamic acid decarboxylase, insulinoma-associated antigen-2, and zinc transporter) are often present in the blood of individuals with type 1 diabetes, which can be additional aids to diagnosis.

Cause of type 2 diabetes

In contrast to type 1 diabetes, type 2 diabetes (non-insulin-dependent diabetes) is characterized by your body’s resistance to the actions of insulin; think of it as having a broken key. This phenomenon is commonly referred to as “insulin resistance.”

As a result, your pancreas eventually can’t keep up with your body’s insulin demands. Eventually, the secretion of insulin significantly decreases, leading to high blood sugar and diabetes.

What are the symptoms of diabetes?

The symptoms of type 1 diabetes typically develop acutely (considered fast), while the symptoms of type 2 diabetes typically develop slowly (considered insidious).

Despite the difference in onset of symptoms, both type 1 and type 2 diabetes share similar symptoms. The “cardinal” symptoms of diabetes are frequent urination (polyuria), excessive thirst (polydipsia), and unintended weight loss. Other symptoms of diabetes may be excessive hunger, fatigue, blurry vision, and tingling or numbness in the hands and/or feet. Two other worrisome symptoms of diabetes are persistent or recurrent infections, especially yeast infections and slow healing wounds.

What are the risk factors for diabetes?

There are a good number of well-known established risk factors for both type 1 and type 2 diabetes.

Risk factors for type 1 diabetes

Type 1 diabetes is not a preventable disease. You are at increased risk of developing the disease for a variety of reasons.

If you have a family history of a first-degree relative (i.e., parent or sibling) with type 1 diabetes, you are at increased for developing the disease. Certain inherited genes, namely HLA genes, can increase your risk of developing type 1 diabetes.

Although type 1 diabetes can develop at any age, children, teens, and young adults are at higher risk for the disease.

Risk factors for type 2 diabetes

In contrast to type 1 diabetes, type 2 diabetes is a potentially preventable disease. Risk factors that increase your chances of developing type 2 diabetes include:

  • being overweight or obese, especially if you are “apple-shaped”;
  • getting too little or no exercise;
  • a diagnosis of high blood pressure (hypertension);
  • a family history of type 2 diabetes in a first-degree relative;
  • race (more common in African Americans, Hispanics, and American Indians), and;
  • age (more common in those older than 45 years old).

Family history, race, and age are considered non-modifiable risk factors, while the rest are modifiable risk factors. In addition, prediabetes or gestational diabetes puts you at increased risk for developing type 2 diabetes in the future.

How is diabetes diagnosed?

The diagnosis of diabetes, whether type 1 or type 2, is relatively simple and made through commonly available blood tests. Most individuals typically come under suspicion due to the presence of cardinal symptoms or through recommended screening.

The following findings are suggestive of a diagnosis of diabetes:

  • A fasting blood sugar test greater than or equal 126 mg/dL;
  • An A1C test greater than or equal to 6.5 percent;
  • A random plasma glucose (sugar) test greater than or equal to 200 mg/dL, and;
  • An oral glucose tolerance test with a blood sugar greater than or equal to 200 mg/dL after two hours.

Doctors recommend a repeat of the abnormal test on a different day in order to confirm a diagnosis of diabetes.

What is the treatment for diabetes?

The foundations for the treatment of diabetes are diet, regular exercise, and medication.

Since your body does not produce insulin in the case of type 1 diabetes, injectable insulin is the main medication used for treatment. In contrast, the treatment of type 2 diabetes utilizes oral and/or injectable drugs, sometimes in combination with injectable insulin. All patients with type 2 diabetes should start on metformin (Glucophage), as it has been proven to reduce diabetic complications.

Other common classes of drugs used to treat this disease include thiazolidinediones, dipeptidyl-peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists (which are injectable), and selective sodium-glucose transporter-2 inhibitors.

What is the prognosis for diabetes?

Today, diabetes is considered an urgent public health issue. In the case of type 2 diabetes, the disease is a direct consequence of the current epidemic of obesity.

Untreated/poorly controlled diabetes, whether type 1 or type 2, increases your risk of long-term complications such as blindness, kidney failure, foot/limb amputations, heart attacks, and strokes. On the other hand, intensive and early treatment with diet, exercise, and medications has the potential to minimize or prevent these complications.

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Jun 19, 2019