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 an important source of energy for the cells that make up your muscles and tissues. It's also your brain'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 but may resolve after the baby is delivered.
Diabetes symptoms vary depending on how much your blood sugar is elevated. Some people, especially those with prediabetes or type 2 diabetes, may not experience symptoms initially. In type 1 diabetes, symptoms tend to come on quickly and be more severe. Some of the signs and symptoms of type 1 and type 2 diabetes include:
Although type 1 diabetes can develop at any age, it typically appears during childhood or adolescence. Type 2 diabetes, the more common type, can develop at any age and is often preventable.
When to see a doctor
To understand diabetes, first you must understand how glucose is normally processed in the body.
How insulin works
The role of glucose
Causes of type 1 diabetes
Causes of prediabetes and type 2 diabetes
Causes of gestational diabetes
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.
Risk factors for diabetes depend on the type of diabetes.
Risk factors for type 1 diabetes
Risk factors for prediabetes and type 2 diabetes
Risk factors for gestational diabetes
Long-term complications of diabetes develop gradually. The longer you have diabetes — and the less controlled your blood sugar — the higher the risk of complications. Eventually, diabetes complications may be disabling or even life-threatening. Possible complications include:
Complications of gestational diabetes
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
Preparing for your appointment
You're likely to start by seeing your primary care doctor if you're having diabetes symptoms. If your child is having diabetes symptoms, you might see your child's pediatrician. If blood sugar levels are extremely high, you'll likely be sent to the emergency room. If blood sugar levels aren't high enough to put you or your child immediately at risk, you may be referred to a doctor who specializes in diabetes, among other disorders (endocrinologist).
Here's some information to help you get ready for your appointment and to know what to expect.
What you can do
Preparing a list of questions can help you make the most of your time with your doctor. For diabetes, some questions to ask include:
Don't hesitate to ask any other questions you have.
What to expect from your doctor
Tests and diagnosis
Symptoms of type 1 diabetes often appear suddenly and are often the reason for checking blood sugar levels. Because symptoms of other types of diabetes and prediabetes come on more gradually or may not be evident, the American Diabetes Association (ADA) has recommended screening guidelines. The ADA recommends that the following people be screened for diabetes:
Tests for type 1 and type 2 diabetes
If the A1C test results aren't consistent, the 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 type 1 diabetes is suspected, your urine will be tested to look for the presence of ketones, a byproduct produced when muscle and fat tissue are used for energy when the body doesn't have enough insulin to use the available glucose. Occasionally a C peptide level — a test used to measure the ability of the pancreas to secrete insulin — may be ordered. Levels of C peptide are usually low in people with type 1 diabetes, but may be normal or high in people with type 2 diabetes.
Tests for gestational diabetes
Your doctor will likely evaluate your risk factors for gestational diabetes early in your pregnancy.
Your doctor may use the following screening tests:
Tests for prediabetes
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:
Treatments and drugs
Depending on what type of diabetes you have, blood sugar monitoring, insulin and oral medications may play a role in your treatment. But no matter what type of diabetes you have, eating a healthy diet, maintaining a healthy weight and monitoring your blood sugar levels are key to managing your diabetes.
Treatments for all types of diabetes
Treatments for type 1 and type 2 diabetes
Treatment for gestational diabetes
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
Sometimes medications — such as metformin (Glucophage, Glumetza, others) — also are an option if you're at high risk of diabetes, including when your prediabetes is worsening or if 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 if you're at high risk. Healthy lifestyle choices remain key, however.
Signs of trouble in any type of diabetes
Lifestyle and home remedies
Diabetes is a serious disease. Following your diabetes treatment plan takes round-the-clock commitment. Careful management of diabetes can reduce your risk of serious — even life-threatening — complications.
No matter what type of diabetes you have:
Lifestyle for type 1 and type 2 diabetes
Above all, stay positive. The good habits you adopt today can help you enjoy an active, healthy life with diabetes.
Numerous substances have been shown in some studies to improve insulin sensitivity, yet other studies have failed to find any benefit for blood sugar control or in lowering A1C levels. Because of the conflicting findings, no alternative therapies are currently recommended for diabetes control. Some of the substances that have shown promise in helping to control blood sugar include:
If you decide that you'd like to try an alternative therapy, don't stop taking the medications that your doctor has prescribed, and discuss the use of any of these therapies with your doctor to be sure that they won't cause adverse reactions or interact with your current therapy.
Additionally, there are no treatments — alternative or conventional — that can cure diabetes, so it's critical that people who are on insulin therapy for diabetes don't stop using insulin unless directed to do so by their physician.
Coping and support
Living with diabetes can be difficult and frustrating. Sometimes, even when you've done everything right, your blood sugar levels may rise. But stick with your diabetes management plan, and you'll likely see a positive difference in your A1C when you visit your doctor.
Because good diabetes management can be time-consuming, and sometimes overwhelming, some people find it helps to talk to someone. Your doctor can probably recommend a mental health professional for you to speak with, or you may want to try a support group. Sharing your frustrations and your triumphs with people who understand what you're going through can be very helpful. And you may find that others have great tips to share about diabetes management. Your doctor may know of a local support group, or you can call the American Diabetes Association at 800-DIABETES (800-342-2383) or the Juvenile Diabetes Research Foundation at 800-533-CURE (800-533-2873).
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, Glumetza, others) may reduce the risk of type 2 diabetes — but healthy lifestyle choices remain essential.
Last Updated: 2013-01-31
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