Type 1 diabetes
Type 1 diabetes
Type 1 diabetes, once known as juvenile diabetes or insulin-dependent diabetes, is a chronic condition in which the pancreas produces little or no insulin, a hormone needed to allow sugar (glucose) to enter cells to produce energy. The far more common type 2 diabetes occurs when the body becomes resistant to the effects of insulin or doesn't make enough insulin.
Various factors may contribute to type 1 diabetes, including genetics and exposure to certain viruses. Although type 1 diabetes typically appears during childhood or adolescence, it also can develop in adults.
Despite active research, type 1 diabetes has no cure, although it can be managed. With proper treatment, people who have type 1 diabetes can expect to live longer, healthier lives than they did in the past.
Type 1 diabetes signs and symptoms can come on quickly and may include:
When to see a doctor
The exact cause of type 1 diabetes is unknown. In most people with type 1 diabetes, the body's own immune system — which normally fights harmful bacteria and viruses — mistakenly destroys the insulin-producing (islet) cells in the pancreas. Genetics may play a role in this process, and exposure to certain viruses may trigger the disease.
The role of insulin
The role of glucose
In type 1 diabetes, there's no insulin to let glucose into the cells, so sugar builds up in your bloodstream, where it can cause life-threatening complications.
The cause of type 1 diabetes is different from the cause of the more familiar type 2 diabetes. In type 2 diabetes, the islet cells are still functioning, but the body becomes resistant to insulin, or the pancreas doesn't produce enough insulin or both.
There aren't many known risk factors for type 1 diabetes, though researchers continue to find new possibilities. Some known risk factors include:
Possible risk factors for type 1 diabetes include:
Some other possible risk factors include:
Type 1 diabetes can affect major organs in your body, including heart, blood vessels, nerves, eyes and kidneys. Keeping your blood sugar level close to normal most of the time can dramatically reduce the risk of many complications.
Long-term complications of type 1 diabetes develop gradually, over years. 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.
Preparing for your appointment
After you've been diagnosed with type 1 diabetes, you'll need close medical follow-up until your blood sugar level stabilizes and your doctor determines the most effective type and doses of insulin for you. A doctor who specializes in hormonal disorders (endocrinologist) generally coordinates diabetes care, but your health care team likely will include:
Once your blood sugar is under control, your endocrinologist likely will recommend checkups every few months. A thorough yearly exam and regular foot and eye exams also are important — especially if your diabetes isn't well controlled, if you have high blood pressure or kidney disease, or if you're pregnant.
It's good to prepare for your appointments, which may include visits with several members of your health care team as well as your primary doctor. Here's some information to help you get ready for your appointment and to know what to expect from your doctor.
What you can do
Preparing a list of questions can help you make the most of your time with your doctor and the rest of your health care team. For type 1 diabetes, topics you want to clarify with your doctor, dietitian or diabetes educator include:
Don't hesitate to ask any other questions.
What to expect from your doctor
What you can do in the meantime
Tests and diagnosis
In June 2009, an international committee of experts from the American Diabetes Association, the European Association for the Study of Diabetes and the International Diabetes Federation recommended that type 1 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:
If you're diagnosed with diabetes, your doctor will also run blood tests to check for autoantibodies that are common in type 1 diabetes. These tests help your doctor distinguish between type 1 and type 2 diabetes. The presence of ketones — byproducts from the breakdown of fat — in your urine also suggests type 1 diabetes, rather than type 2.
After the diagnosis
Compared with repeated daily blood sugar tests, A1C testing better indicates how well your diabetes treatment plan is working. An elevated A1C level may signal the need for a change in your insulin regimen, meal plan or both.
In addition to the A1C test, the doctor will also take blood and urine samples periodically to check your cholesterol levels, thyroid function, liver function and kidney function. The doctor will also examine you to assess your blood pressure, and he or she will check the sites where you test your blood sugar and deliver insulin.
Treatments and drugs
Treatment for type 1 diabetes is a lifelong commitment to:
The goal is to keep your blood sugar level as close to normal as possible to delay or prevent complications. Although there are exceptions, generally, the goal is to keep your daytime blood sugar levels before meals between 80 and 120 mg/dL (4.4 to 6.7 mmol/L) and your bedtime numbers between 100 and 140 mg/dL (5.6 to 7.8 mmol/L).
If managing your diabetes seems overwhelming, take it one day at a time. And remember that you're not alone. You'll work closely with your diabetes treatment team to keep your blood sugar level as close to normal as possible.
Insulin and other medications
Types of insulin are many and include:
Examples are regular insulin (Humulin 70-30, Novolin 70/30, others), insulin isophane (Humulin N, Novolin N), insulin lispro (Humalog) and insulin aspart (Novolog). Long-acting insulins include glargine (Lantus) and detemir (Levemir).
Depending on your needs, your doctor may prescribe a mixture of insulin types to use throughout the day and night.
Insulin can be administered using:
An emerging treatment approach, not yet available, is closed loop insulin delivery, also known as the artificial pancreas. It links a continuous glucose monitor to an insulin pump. The device automatically delivers the correct amount of insulin when the monitor indicates the need for it. Testing has shown encouraging results, but more research is needed.
Insulin can't be taken orally to lower blood sugar because stomach enzymes interfere with insulin's action.
Oral medications, however, are sometimes prescribed, such as:
Your doctor might also prescribe pramlintide (Symlin). An injection of this medication before you eat can slow the movement of food through your stomach to curb the sharp increase in blood sugar that occurs after meals.
Healthy eating and monitoring carbohydrates
You'll eat fewer animal products and refined carbohydrates, such as white bread and sweets. This is the best overall eating plan, even for people without diabetes.
You'll need to learn how to assess the carbohydrates in the foods you eat so that you can give yourself enough insulin to properly metabolize those carbohydrates. A registered dietitian can help you create a meal plan that fits your health goals, food preferences and lifestyle.
Remember that physical activity lowers blood sugar, often for long after you're done working out. If you begin a new activity, check your blood sugar level more often than usual until you know how that activity affects your blood sugar levels. You might need to adjust your meal plan or insulin doses to compensate for the increased activity. If you use an insulin pump, you can set a temporary basal rate to keep your blood sugar from dropping. Ask your doctor or diabetes educator to show you how.
Blood sugar monitoring
Even if you take insulin and 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:
Continuous glucose monitoring (CGM) is the newest way to monitor blood sugar levels, and may be most helpful for people who have developed hypoglycemia unawareness. Continuous glucose monitors attach to the body using a fine needle just under the skin that checks blood glucose level every few minutes. CGM isn't yet considered as accurate as standard blood sugar monitoring, so it's not considered a replacement method for keeping track of blood sugar, but an additional measure for some people.
Signs of trouble
Low blood sugar (hypoglycemia). This occurs when your blood sugar level drops below your target range. Ask your doctor what's considered a low blood sugar level for you. Blood sugar levels can drop for many reasons, including skipping a meal, getting more physical activity than normal or injecting too much insulin.
Learn the symptoms of low blood sugar, and test your blood sugar if you think your blood sugar levels are dropping. When in doubt, always do a blood sugar test. Early signs and symptoms of low blood sugar include:
Later signs and symptoms of low blood sugar, which can sometimes be mistaken for alcohol intoxication in teens and adults include:
If you develop hypoglycemia during the night, you might wake with sweat-soaked pajamas or a headache. Thanks to a natural rebound effect, nighttime hypoglycemia might cause an unusually high blood sugar reading first thing in the morning.
If you have a low blood sugar reading:
If a blood glucose meter isn't readily available, treat for low blood sugar anyway if you have symptoms of hypoglycemia, and then test as soon as possible.
Always carry a source of fast-acting sugar with you. Left untreated, low blood sugar will cause you to lose consciousness. If this occurs, you may need an emergency injection of glucagon — a hormone that stimulates the release of sugar into the blood. Be sure you always have a glucagon emergency kit available — at home, at work, when you're out — and make sure it hasn't expired.
Hypoglycemia unawareness. Some people may lose the ability to sense that their blood sugar levels are getting low, because they've developed a condition known as hypoglycemia unawareness. With hypoglycemia unawareness, the body no longer reacts to a low blood sugar with symptoms such as lightheadedness or headaches. The more you experience low blood sugars, the more likely you are to develop hypoglycemia unawareness. The good news is that if you can avoid having a hypoglycemic episode for several weeks, you may start to become more aware of impending lows.
High blood sugar (hyperglycemia). Your blood sugar can rise for many reasons, including eating too much, eating the wrong types of foods, not taking enough insulin or illness.
If you suspect hyperglycemia, check your blood sugar. You might need to adjust your meal plan or medications. If your blood sugar is higher than your target range, you'll likely need to administer a "correction" using an insulin shot or through an insulin pump. A correction is an additional dose of insulin that should bring your blood sugar back into the normal range. High blood sugar levels don't come down as quickly as they go up. Ask your doctor how long to wait until you recheck. If you use an insulin pump, random high blood sugar readings may mean you need to change the pump site.
If you have two consecutive blood sugar readings above 250 mg/dL (13.9 mmol/L), test for ketones using a urine test stick. Don't exercise if your blood sugar level is very high or if ketones are present. If only a trace or small amounts of ketones are present, drink extra fluids to flush out the ketones.
If your blood sugar is persistently above 300 mg/dL (16.7 mmol/L), call your doctor or seek emergency care.
Increased ketones in your urine (diabetic ketoacidosis). If your cells are starved for energy, your body may begin to break down fat — producing toxic acids known as ketones.
Signs and symptoms of this serious condition include:
If you suspect ketoacidosis, check your urine for excess ketones with an over-the-counter ketones test kit. If you have large amounts of ketones in your urine, call your doctor right away or seek emergency care. Also, call your doctor if you have vomited more than once and you have ketones in your urine.
An insulin pump is a device about the size of a cell phone that's 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 ...
Lifestyle and home remedies
Type 1 diabetes is a serious disease. Following your diabetes treatment plan takes round-the-clock commitment, which can be frustrating at times. But realize that your efforts are worthwhile. Careful management of type 1 diabetes can reduce your risk of serious — even life-threatening — complications. Consider these tips:
Above all, stay positive. The good habits you adopt today can help you enjoy an active, healthy life with type 1 diabetes.
Coping and support
Living with type 1 diabetes isn't easy. Good diabetes management requires a lot of time and effort, especially in the beginning.
Diabetes can affect your emotions both directly and indirectly. Poorly controlled blood sugar can directly affect your emotions by causing behavior changes, such as irritability. Diabetes may also make you feel different from other people, and there may be times you feel resentful that you always have to incorporate diabetes planning in everything you do.
People with diabetes have an increased risk of depression and anxiety, which may be why many diabetes specialists regularly include a social worker or psychologist as part of their diabetes care team.
You may find that talking to other people with type 1 diabetes is helpful. There are support groups available both online and in person. Although support groups aren't for everyone, they can be good sources of information. Group members often know about the latest treatments and tend to share their own experiences or helpful information, such as where to find carbohydrate counts for your favorite takeout restaurant. If you're interested, your doctor may be able to recommend a group in your area.
Or you can visit the websites of the American Diabetes Association (ADA) or the Juvenile Diabetes Research Foundation (JDRF) for support group information and to check out local activities for people with type 1 diabetes. You can also reach the ADA at 800-DIABETES (800-342-2383) or JDRF at 800-533-CURE (800-533-2873).
There's no known way to prevent the type 1 diabetes. But researchers are working on preventing the disease or further destruction of the islet cells in people who are newly diagnosed. Ask your doctor if you might be eligible for one of these trials, but carefully weigh the risks and benefits of any treatment available in a clinical trial.
You can find more information on the types of research being done from TrialNet, a collaboration of diabetes researchers. TrialNet is also conducting a natural history study to check for diabetes genes in parents, children and siblings of people with type 1 diabetes.
Last Updated: 2013-01-23
© 1998-2014 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "Mayo Clinic Health Information," "Reliable information for a healthier life" and the triple-shield Mayo logo are trademarks of Mayo Foundation for Medical Education and Research.
Terms and conditions of use