Filed under: Diabetes
The term "diabetes mellitus" refers to a group of diseases that affect how your body uses blood glucose, commonly called blood sugar. Glucose is vital to your health because it's the main source of energy for the cells that make up your muscles and tissues. It's your body's main source of fuel.
If you have diabetes, no matter what type, it means you have too much glucose in your blood, although the reasons may differ. Too much glucose can lead to serious health problems.
Chronic diabetes conditions include type 1 diabetes and type 2 diabetes. Potentially reversible diabetes conditions include prediabetes — when your blood sugar levels are higher than normal, but not high enough to be classified as diabetes — and gestational diabetes, which occurs during pregnancy.
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Diabetes symptoms vary somewhat, depending on what type of diabetes you have. If you have prediabetes or gestational diabetes, you may not experience symptoms. Or you might experience some or all of the symptoms of type 1 and type 2 diabetes:
Although type 1 diabetes can develop at any age, it typically appears during childhood or adolescence. Type 2 diabetes, the most common type, can develop at any age and is often preventable.
When to see a doctor
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
To understand diabetes, first you must understand how glucose is normally processed in the body.
How glucose normally works
Glucose is a main source of energy for the cells that make up your muscles and other tissues. Glucose comes from two major sources: the food you eat and your liver. During digestion, sugar is absorbed into the bloodstream. Normally, sugar then enters cells with the help of insulin.
The hormone insulin comes from the pancreas, a gland located just behind the stomach. When you eat, your pancreas secretes insulin into your bloodstream. As insulin circulates, it acts like a key by unlocking microscopic doors that allow sugar to enter your cells. Insulin lowers the amount of sugar in your bloodstream. As your blood sugar level drops, so does the secretion of insulin from your pancreas.
Your liver acts as a glucose storage and manufacturing center. When you haven't eaten in a while, for example, your liver releases stored glucose to keep your glucose level within a normal range.
Causes of type 1 diabetes
In type 1 diabetes, your immune system — which normally fights harmful bacteria or viruses — attacks and destroys the insulin-producing cells in the pancreas. This leaves you with little or no insulin. Instead of being transported into your cells, sugar builds up in your bloodstream.
Causes of prediabetes and type 2 diabetes
In prediabetes — which can lead to type 2 diabetes — and in type 2 diabetes, your cells become resistant to the action of insulin, and your pancreas is unable to make enough insulin to overcome this resistance. Instead of moving into your cells, sugar builds up in your bloodstream. Exactly why this happens is uncertain, although excess fat — especially abdominal fat — and inactivity seem to be important factors.
Causes of gestational diabetes
During pregnancy, the placenta produces hormones to sustain your pregnancy. These hormones make your cells more resistant to insulin. As your placenta grows larger in the second and third trimesters, it secretes more of these hormones — making it even harder for insulin to do its job.
Normally, your pancreas responds by producing enough extra insulin to overcome this resistance. But sometimes your pancreas can't keep up. When this happens, too little glucose gets into your cells and too much stays in your blood. This is gestational diabetes.
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Risk factors for diabetes depend on the type of diabetes.
Risk factors for type 1 diabetes
Although the exact cause of type 1 diabetes is unknown, family history may play a role. Your risk of developing type 1 diabetes increases if you have a parent or sibling who has type 1 diabetes. Other factors have been proposed, as well, such as exposure to a viral illness.
Risk factors for prediabetes and type 2 diabetes
Researchers don't fully understand why some people develop prediabetes and type 2 diabetes and others don't. It's clear that certain factors increase the risk, however, including:
Other conditions associated with diabetes include:
When these conditions — high blood pressure, high blood sugar and abnormal blood fats — occur together with obesity, they are associated with resistance to insulin.
Risk factors for gestational diabetes
Any pregnant woman can develop gestational diabetes, but some women are at greater risk than are others. Risk factors for gestational diabetes include:
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Diabetes complications vary depending on the type of diabetes you have.
Complications of type 1 and type 2 diabetes
Short-term complications of type 1 and type 2 diabetes require immediate care. Left untreated, these conditions can cause seizures and a state of unconsciousness (coma).
Long-term complications of diabetes develop gradually. The earlier you develop diabetes — and the less controlled your blood sugar — the higher the risk of complications. Eventually, diabetes complications may be disabling or even life-threatening.
Complications of gestational diabetes
Most women who have gestational diabetes deliver healthy babies. However, untreated or uncontrolled blood sugar levels can cause problems for you and your baby.
Complications in your baby can occur as a result of gestational diabetes:
Complications in you can also occur as a result of gestational diabetes:
Complications of prediabetes
Prediabetes may develop into type 2 diabetes.
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
You're likely to start by first seeing your family doctor or a general practitioner. However, in some cases when you call to set up an appointment, you may be referred immediately to an endocrinologist, who specializes in diabetes, among other disorders.
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. List your questions from most important to least important in case time runs out. For diabetes, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Tests for type 1 and type 2 diabetes
In June 2009, an international committee composed of experts from the American Diabetes Association, the European Association for the Study of Diabetes and the International Diabetes Federation recommended that type 1 and type 2 diabetes testing include the:
If the A1C test isn't available, or if you have certain conditions that can make the A1C test inaccurate — such as if you're pregnant or have an uncommon form of hemoglobin (known as a hemoglobin variant) — your doctor may use the following tests to diagnose diabetes:
Tests for gestational diabetes
Screening for gestational diabetes is a routine part of prenatal care. Most health care providers recommend a blood test known as a glucose challenge test between the 24th and 28th weeks of pregnancy — or earlier if you're at particularly high risk of gestational diabetes.
You'll begin the glucose challenge test by drinking a syrupy glucose solution. One hour later, you'll have a blood test to measure your blood sugar level. A blood sugar level above 140 mg/dL (7.8 mmol/L) usually indicates gestational diabetes, but you'll likely need a second test to confirm the diagnosis.
For the follow-up test, you'll be asked to fast overnight. Then you'll drink another sweet solution — this one containing a higher concentration of glucose — and your blood sugar level will be checked every hour for a period of three hours.
Tests for prediabetes
The American College of Endocrinology suggests prediabetes testing for anyone who has a family history of type 2 diabetes and for those who are obese or have metabolic syndrome. Women with a personal history of gestational diabetes also should be tested.
The primary test to screen for prediabetes is the:
If the A1C test isn't available, or if you have certain conditions that can make the A1C test inaccurate — such as if you're pregnant or have an uncommon form of hemoglobin (known as a hemoglobin variant) — your doctor may use the following tests to diagnose diabetes:
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Depending on what type of diabetes you have, blood sugar monitoring, insulin and oral medications may play a role in your treatment. A pancreas transplant may be an option for select people.
But no matter what type of diabetes you have, maintaining a healthy diet, exercising and keeping a healthy weight are all keys to managing your diabetes.
Treatments for all types of diabetes
An important part of managing all types of diabetes includes maintaining a healthy weight through a healthy diet and exercise plan:
Healthy eating. Contrary to popular perception, there's no diabetes diet. You won't be restricted to boring, bland foods. Instead, you'll need plenty of fruits, vegetables and whole grains — foods that are high in nutrition and low in fat and calories — and fewer animal products and sweets. In fact, it's the best eating plan for the entire family. Even sugary foods are OK once in a while, as long as they're included in your meal plan.
Yet understanding what and how much to eat can be a challenge. A registered dietitian can help you create a meal plan that fits your health goals, food preferences and lifestyle. Once you've covered the basics, remember the importance of consistency. To keep your blood sugar on an even keel, try to eat the same amount of food with the same proportion of carbohydrates, proteins and fats at the same time every day.
Treatments for type 1 and type 2 diabetes
Treatment for type 1 and type 2 diabetes primarily involves monitoring of your blood sugar along with insulin, other diabetes medications or both.
Monitoring your blood sugar. Depending on your treatment plan, you may check and record your blood sugar level several times a week to several times a day. Careful monitoring is the only way to make sure that your blood sugar level remains within your target range.
Even if you eat on a rigid schedule, the amount of sugar in your blood can change unpredictably. With help from your diabetes treatment team, you'll learn how your blood sugar level changes in response to things like food, physical activity, medications, illness, alcohol, stress and — for women — fluctuations in hormone levels.
In addition to daily blood sugar monitoring, your doctor may recommend regular A1C testing to measure your average blood sugar level for the past two to three months. Compared with repeated daily blood sugar tests, A1C testing better indicates how well your diabetes treatment plan is working overall. An elevated A1C level may signal the need for a change in your insulin regimen or meal plan. Your target A1C goal may vary depending on your age and various other factors. However, for most people, the American Diabetes Association recommends an A1C of below 7 percent. Ask your doctor what your A1C target is.
Insulin. Anyone who has type 1 diabetes needs insulin therapy to survive. Some people with type 2 diabetes need insulin, as well. Because stomach enzymes interfere with insulin taken by mouth, oral insulin isn't an option for lowering blood sugar. Often, insulin is injected using a fine needle and syringe or an insulin pen — a device that looks like an ink pen, except the cartridge is filled with insulin.
An insulin pump also may be an option. The pump is a device about the size of a cell phone worn on the outside of your body. A tube connects the reservoir of insulin to a catheter that's inserted under the skin of your abdomen. The pump is programmed to dispense specific amounts of insulin automatically. It can be adjusted to deliver more or less insulin depending on meals, activity level and blood sugar level.
Many types of insulin are available, including rapid-acting insulin, long-acting insulin and intermediate options. Depending on your needs, your doctor may prescribe a mixture of insulin types to use throughout the day and night.
Treatment for gestational diabetes
Controlling your blood sugar level is essential to keeping your baby healthy and avoiding complications during delivery. In addition to maintaining a healthy diet and exercising, your treatment plan may include monitoring your blood sugar and, in some cases, using insulin.
Your health care provider will also monitor your blood sugar level during labor. If your blood sugar rises, your baby may release high levels of insulin — which can lead to low blood sugar right after birth.
Treatment for prediabetes
If you have prediabetes, healthy lifestyle choices can help you bring your blood sugar level back to normal or at least keep it from rising toward the levels seen in type 2 diabetes. Maintaining a healthy weight through exercise and healthy eating can help.
Sometimes medications — such as the oral diabetes drugs metformin (Glucophage) and acarbose (Precose) — also are an option if you're at high risk of diabetes. This includes if your prediabetes is worsening or you have cardiovascular disease, fatty liver disease or polycystic ovary syndrome.
In other cases, medications to control cholesterol — statins, in particular — and high blood pressure medications are needed. Your doctor might prescribe low-dose aspirin therapy to help prevent cardiovascular disease. Healthy lifestyle choices remain key, however.
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Diabetes is a serious disease. Following your diabetes treatment plan takes round-the-clock commitment. But your efforts are worthwhile. Careful management of diabetes can reduce your risk of serious — even life-threatening — complications.
Lifestyle for all diabetes
No matter what type of diabetes you have:
Lifestyle for type 1 and type 2 diabetes
In addition, if you have type 1 or type 2 diabetes:
Above all, stay positive. The good habits you adopt today can help you enjoy an active, healthy life with diabetes.
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.
Type 1 diabetes can't be prevented. However, the same healthy lifestyle choices that help treat prediabetes, type 2 diabetes and gestational diabetes can help prevent them.
Sometimes medication is an option as well. Oral diabetes drugs such as metformin (Glucophage) and rosiglitazone (Avandia) may reduce the risk of type 2 diabetes — but healthy lifestyle choices remain essential.
©1998-2009 Mayo Foundation for Medical Education and Research (MFMER). Terms of use.

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