Type 2 Diabetes Overview
Type 2 diabetes, is a common chronic metabolic disease that leads to abnormally high levels of blood sugar in the blood. This blood sugar is al...

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What Is Type 2 Diabetes?

Type 2 diabetes, formerly called adult-onset diabetes and non insulin-dependent diabetes, is a chronic condition characterized by high levels of glucose (sugar) in the blood. Although some people can manage symptoms by losing weight and following a healthy diet and exercise plan, most people with type 2 diabetes will have it for life.

According to the American Diabetes Association (ADA), nearly 26 million people in the U.S. have diabetes; most of these people have type 2 diabetes, and as many as 7 million people are undiagnosed (ADA, 2011). Almost 80 million more have “prediabetes”—the precursor to type 2 diabetes.

What Are Causes of Type 2 Diabetes?

Type 2 diabetes is caused by a problem with the way the body produces and/or uses insulin. Insulin helps the body move sugar from your blood into your cells for energy.

In some people, the body stops producing enough insulin to move the glucose out of the blood and into the body’s cells. In others, the muscles and tissues begin to resist or ignore the insulin, which causes the sugar to stay in the blood. Type 2 diabetes develops over time. As the body slowly loses the ability to make or use insulin, the sugar can build up, which causes high blood sugar, called hyperglycemia. Hyperglycemia in people with diabetes can occur for a number of reasons, such as overeating, exercising too little, stress, or illness. These high blood sugar levels can cause problems in the body over time.

Being overweight increases the chances of being diagnosed with type 2 diabetes. Other factors can increase the risk for type 2 diabetes as well, including poor diet or being underweight.

What Are Symptoms of Type 2 Diabetes

Some people may have type 2 diabetes for years without noticing any symptoms. Early signs and symptoms of this condition may include:

  • the frequent need to urinate
  • feeling very hungry or thirsty
  • feeling very tired
  • frequent infections of the urinary tract or skin
  • blurry vision
  • erectile dysfunction
  • tingling, pain, or numbness in hands or feet

People experiencing these symptoms should seek care promptly from a health professional and ask to be tested for diabetes.

What Are Risk Factors for Type 2 Diabetes?

A type 2 diabetes diagnosis can occur in virtually anyone. Risk factors for type 2 diabetes include:

  • being overweight (BMI of 25 or greater), particularly around the midsection
  • exercising less than three times per week
  • having had gestational diabetes or given birth to a baby nine pounds or larger
  • having a family history of type 2 diabetes
  • blood pressure of 140/90 mmHg or higher or being on medications for high blood pressure
  • HDL cholesterol below 35 mg/dL
  • high blood triglyceride levels over 250 mg/dL
  • being over the age of 45
  • having a diagnosis of polycystic ovary syndrome, metabolic syndrome, or acanthosis nigricans
  • Being a high-risk ethnicity (African Americans, Asian Americans, Latinos, Native Americans or Pacific Islanders)

How Does Type 2 Diabetes Differ from Type 1 Diabetes?

Type 2 diabetes is most commonly diagnosed in adults. More than one in four adults aged 65 or over have the condition (ADA, 2011). Type 1 diabetes, formerly known as juvenile diabetes or insulin-dependent diabetes, can occur at any age but is most commonly diagnosed in children and young adults.

People with type 1 diabetes are unable to produce insulin. Individuals with type 2 diabetes may produce insulin but have cells that are resistant to insulin. In both forms of diabetes, glucose can build up in the blood if treatment is not started.

The exact cause of type 1 diabetes is unknown, but there is a significant hereditary link and it may be an autoimmune disorder. There is no cure for type 1 diabetes, and virtually all diagnosed individuals use insulin every day to help their body process the glucose in their blood.

Some people with type 2 diabetes may avoid the need for medication with a healthy diet and lifestyle, and some can even eliminate their need for medication by losing weight and exercising. People with type 1 and type 2 diabetes need to carefully track their blood glucose levels to avoid hypo- or hyperglycemia. The symptoms and tests for each type of diabetes can be similar.

How Is Type 2 Diabetes Diagnosed?

If you have any of the common symptoms of diabetes or if you are at a high risk due to age, weight, ethnicity, heredity, or health status, you may be tested yearly or every three years for diabetes. The most common tests for diagnosing type 2 diabetes include the hemoglobin A1C test, fasting blood glucose tests, oral glucose tolerance tests, and random glucose testing. Many physicians will need to test glucose at more than one visit to make a diagnosis of type 2 diabetes.

What Are Treatments for Type 2 Diabetes?

In addition to monitoring blood glucose levels, two other main treatments for type 2 diabetes include diet and exercise. Some people may also need diabetes medicine, including insulin. Oral diabetes medications are available for people with type 2 diabetes to help manage blood sugar levels. If needed, insulin can also be used.

Type 2 Diabetes Diet

Eating a healthy, balanced diet can help manage blood sugar and prevent diabetes complications. There are many different meal plans to choose from, and you will need to find the one that works best for you. Working with a dietitian to learn about a healthy diabetes diet can make the transition easier.

Although entire books have been devoted to the subject, there are some simple tricks to following a healthy diet for diabetes. Planning meals in advance and learning to pay attention to the amount of carbohydrates, in foods can help make a diabetes diet simpler. Most people with type 2 diabetes will need to manage calorie intake and their weight, as well. Sometimes, weight loss can help reverse diabetes symptoms and blood glucose problems.

In general, people with type 2 diabetes should limit intake of processed whole grains that are high in fiber, and aim for a steady amount of carbohydrates with each meal. A healthy diabetes diet will also include plenty of vegetables, lean protein, fresh fruits, healthy fats, and low-fat dairy (NIH, 2011). Aim to fill at least half of your plate at each meal with vegetables; the other half should be split between a lean protein (like chicken or fish) and a healthy starch or grain (like brown rice or beans) (ADA, 2012).

Exercise for Type 2 Diabetics

Most people with type 2 diabetes can benefit from regular physical activity. Exercise can help control blood sugar levels and even help reverse insulin resistance.

Individuals with type 2 diabetes should incorporate physical activity into their daily routine on a regular basis. If they were previously inactive, they can slowly build their way up to regular exercise by starting with a short walk every evening or some gentle stretching. Diabetics should aim for about 30 minutes of moderate physical activity at least five days each week.

Coupled with a healthy diet, exercise can be one of the most effective treatments for diabetes. Weight loss and exercise can help people with diabetes avoid the need for oral medications and prevent some complications of the disease.

What Is the Outlook for Type 2 Diabetes?

Diabetes can cause serious health problems. It is most dangerous when it is poorly controlled. People who don’t manage their blood glucose levels, have other health problems, are inactive, or are undergoing a lot of stress may experience serious complications of this disease both short and long term.

Problems like hyper- and hypoglycemia can cause weakness, fatigue, and confusion. Over time, high blood sugar levels can affect many of the organs of the body and cause damage, such as nerve and organ damage. High blood sugar levels have a slow and cumulative effect. Over time, the damage to nerves, blood vessels, and organs can cause serious health problems. These include vision problems, foot and skin problems, recurrent infections, heart problems, kidney disease or failure, pain and numbness in limbs, or amputation of the feet or legs. According to the American Diabetes Association, diabetes plays a factor in nearly a quarter of a million deaths each year (ADA, 2011).

Despite these serious potential complications, type 2 diabetes can be safely managed. Many people live long, healthy lives despite having diabetes. With proper management, most or all of these serious side effects can be avoided.

Preventing Type 2 Diabetes

Diabetes prevention involves a healthy lifestyle. In most cases, type 2 diabetes can be prevented by maintaining a healthy body weight, eating a balanced diet, and staying physically active. Individuals who are prediabetic or at a high risk of developing type 2 diabetes should take extra care to exercise and maintain a healthy weight.

In addition to their importance in diagnosing diabetes, blood sugar levels are crucial to staying healthy for people with diabetes. Diet and physical activity can directly affect blood sugar levels. Blood glucose changes naturally throughout the day, but it is usually higher after meals and lower after sleeping or fasting.

A healthy fasting blood glucose range is 70–100 mg/dL. Your doctor may suspect diabetes if you have a random blood sugar level above 200 mg/dL or if you test equal to or higher than 126 mg/dL for fasting glucose levels on two occasions. Blood sugar can be checked quickly at home with a simple device.

Individuals with type 2 diabetes may need to track their blood sugar levels to know how well they are managing their condition, especially if they are on medication that increases the amount of insulin in the body. If blood sugar levels get too high (hyperglycemia) or too low (hypoglycemia), serious health problems can occur. Glucose monitoring, exercise, and diet management are among the most common treatments for type 2 diabetes.

In order to prevent complications and the negative symptoms of type 2 diabetes, an individual treatment plan is essential. Managing blood sugar on a daily basis, following a healthy diet, and being physically active can all help to prevent many dangerous complications.

Maintaining a healthy blood pressure and keeping stress under control is also important to preventing complications. Taking care of your feet by cleaning, drying, and checking them regularly can also be important to preventing problems. Sometimes, diabetes medications and other pharmaceuticals are used to protect health and prevent complications. These drugs help manage blood sugar, blood pressure, or other health problems that can impact the body’s ability to function safely.

Written by: Katherine Brind'Amour
Edited by:
Medically Reviewed by: Peggy Pletcher, MS, RD, LD, CDE
Published: Jan 24, 2012
Published By: Healthline Networks, Inc.
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