Diagnosis

The glycated hemoglobin test most often diagnoses type 2 diabetes. Also called the A1C test, it reflects the average blood sugar level for the past two to three months. Results mean the following:

  • Below 5.7% is healthy.
  • 5.7% to 6.4% is prediabetes.
  • 6.5% or higher on two separate tests means diabetes.

If there are no A1C tests or if you have certain conditions that get in the way of A1C test results, your healthcare professional may use the following tests to diagnose diabetes:

Random blood sugar test. Blood sugar values show in milligrams of sugar per deciliter (mg/dL) or millimoles of sugar per liter (mmol/L) of blood. It doesn't matter when you last ate. A level of 200 mg/dL (11.1 mmol/L) or higher suggests diabetes. This is most likely if you also have symptoms of diabetes, such as urinating often and being very thirsty.

Fasting blood sugar test. You give a blood sample for testing after not eating overnight. Results are as follows:

  • Less than 100 mg/dL (5.6 mmol/L) is healthy.
  • 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is prediabetes.
  • 126 mg/dL (7 mmol/L) or higher on two tests is diabetes.

Oral glucose tolerance test. This mainly tests the blood sugar of people who are pregnant and those who have cystic fibrosis. You don't eat for a certain amount of time. Then you drink a sugary liquid at your healthcare team's office. You give blood samples over two hours to test blood sugar levels. Results are as follows:

  • Less than 140 mg/dL (7.8 mmol/L) after two hours is healthy.
  • 140 to 199 mg/dL (7.8 mmol/L and 11.0 mmol/L) is prediabetes.
  • 200 mg/dL (11.1 mmol/L) or higher after two hours suggests diabetes.

Screening. The American Diabetes Association suggests that all adults age 35 or older have routine tests for type 2 diabetes. Others to be tested include:

  • People younger than 35 who are overweight or obese and have one or more risk factors linked to diabetes.
  • Women who had diabetes while pregnant, called gestational diabetes.
  • People who have been diagnosed with prediabetes.
  • Children who are overweight or obese and who have a family history of type 2 diabetes or other risk factors.

After a diagnosis

If you're diagnosed with diabetes, your healthcare professional may do other tests to see whether you have type 1 or type 2 diabetes. Treatment depends on which condition you have.

Your healthcare team tests A1C levels at least two times a year and when your treatment changes. Target A1C goals depend on age and other factors. For most people, the American Diabetes Association suggests an A1C level below 7%.

You also have other tests to screen for complications of diabetes and other medical conditions.

Treatment

Living with type 2 diabetes involves learning about the condition and lifestyle changes. Diabetes education is an important part of managing the condition. Management includes:

  • Healthy eating.
  • Regular exercise.
  • Weight loss if needed.
  • Diabetes medicine or insulin therapy if needed.
  • Keeping track of blood sugar.

These steps make it more likely that blood sugar will stay in a healthy range. And they may help delay or prevent complications.

Healthy eating

There's no diabetes diet. But it's good to focus your eating on:

  • A regular schedule for meals and healthy snacks.
  • Smaller amounts of food.
  • More high-fiber foods, such as fruits, nonstarchy vegetables and whole grains.
  • Fewer refined grains, starchy vegetables and sweets.
  • Modest servings of low-fat dairy, low-fat meats and fish.
  • Healthy cooking oils, such as olive oil or canola oil.
  • Fewer calories.

You may see a registered dietitian, who can help you:

  • Make healthy food choices.
  • Plan healthy meals.
  • Make new habits and learn what stops you from changing habits.
  • Watch carbohydrate intake to keep your blood sugar levels more stable.

Physical activity

Exercise is important to lose weight or stay at a healthy weight. It also helps manage blood sugar. Talk with your healthcare team before starting or changing your exercise program to make sure the activities are safe for you.

  • Aerobic activity. Choose activities that you enjoy. Try walking, swimming, biking or running. Aim to get about 30 minutes or more of moderate aerobic exercise on most days of the week, or at least 150 minutes a week.
  • Strength training. Strength training increases your strength, balance and ability to do activities of daily living. Strength training can be done using free weights, resistance tubes, weight machines or your body weight for resistance. Aim to do strength training exercises for all major muscle groups at least two times a week.
  • Move more. Breaking up long periods of inactivity, such as sitting at the computer, can help control blood sugar levels. Take a few minutes to stand, walk around or do some light activity every 30 minutes.

Weight loss

Losing weight can help you manage blood sugar levels, cholesterol, triglycerides and blood pressure. If you're overweight, you may see these factors improve after you lose as little as 5% of your body weight. The more weight you lose, the better it is for your health.

Your healthcare professional or dietitian can help you set good weight-loss goals and make lifestyle changes to help you reach them.

Tracking your blood sugar

Your healthcare team will tell you how often to check your blood sugar level. This is to make sure that your blood sugar stays in the target range. You may, for instance, need to check it once a day and before or after exercise. If you take insulin, you may need to check your blood sugar several times a day.

You can use a small, at-home device called a blood glucose meter. This measures the amount of sugar in a drop of blood. Keep a record to share with your healthcare team.

Continuous glucose monitoring is an electronic system that records blood sugar levels every few minutes from a sensor put under the skin. The sensor most often is in the arm. The system can send results to a mobile device such as a phone. And the system can alert you when levels are too high or too low.

Diabetes medicines

If you can't stay at your target blood sugar level with diet and exercise, your healthcare team may prescribe diabetes medicines that help lower glucose levels. Or you may start insulin therapy. Medicines for type 2 diabetes include the following.

Metformin (Fortamet, Glumetza, others) is most often the first medicine prescribed for type 2 diabetes. It works mainly in two ways. It lowers the amount of glucose the liver makes. And it helps the body use insulin better.

Some people who take metformin, may get B-12 deficiency and may need to take supplements. There are other side effects that may get better over time. Side effects might include:

  • Nausea.
  • Belly pain.
  • Bloating.
  • Diarrhea.

Sulfonylureas help the body make more insulin. These include glipizide (Glucotrol XL) and glimepiride (Amaryl). Side effects might include:

  • Low blood sugar.
  • Weight gain.

Another sulfonylurea is glyburide (DiaBeta, Glynase). It has a higher risk of low blood sugar.

Glinides help the pancreas to make more insulin. They work faster than sulfonylureas. But their effect doesn't last as long. They include repaglinide and nateglinide. Side effects might include:

  • Low blood sugar.
  • Weight gain.

Thiazolidinediones help the body's tissues take in more insulin. These include pioglitazone (Actos) and rosiglitazone. Side effects might include:

  • Weight gain.
  • Broken bones.
  • Fluid retention.
  • Heart failure.

DPP-4 inhibitors help lower blood sugar levels. But they tend to have only a small effect. Medicines include alogliptin (Nesina), sitagliptin (Januvia), saxagliptin and linagliptin (Tradjenta). Side effects might include:

  • Pancreatitis.
  • Joint pain.

GLP-1 receptor agonists are medicines taken by shot, called injection. They slow digestion and help lower blood sugar levels. Their use is often linked with weight loss. Some lower the risk of heart attack and stroke.

These medicines include dulaglutide (Trulicity) exenatide (Byetta, Bydureon Bcise), liraglutide (Saxenda, Victoza) and semaglutide (Rybelsus, Ozempic, Wegovy). Side effects might include:

  • Nausea.
  • Vomiting.
  • Diarrhea.

SGLT2 inhibitors affect the how the kidneys filter blood. They block the return of glucose to the bloodstream. Excess glucose then leaves the body in the urine. These medicines may lower the risk of heart attack and stroke in people with a high risk of those conditions.

These medicines include canagliflozin (Invokana), dapagliflozin (Farxiga) and empagliflozin (Jardiance). Side effects might include:

  • Vaginal yeast infections.
  • Urinary tract infections.
  • Low blood pressure.
  • High cholesterol.
  • Gangrene.
  • Broken bones.
  • Risk of amputation.

Other medicines your healthcare professional might prescribe are medicines to lower blood pressure and cholesterol. Low-dose aspirin may help prevent heart and blood vessel conditions.

Insulin therapy

Some people who have type 2 diabetes need insulin therapy. In the past, people tried insulin therapy only after other treatments had failed. But today, it may be prescribed sooner if lifestyle changes and other medicines don't manage blood sugar levels.

Insulin types vary by how quickly they work and how long they last. Long-acting insulin, for instance, works overnight or throughout the day to keep blood sugar levels even. People most often take short-acting insulin at mealtimes.

Your healthcare professional prescribes the type of insulin that's right for you and advises you when to take it. Your insulin type, dosage and schedule may change. That depends on how stable your blood sugar levels are. People take most types of insulin as an injection.

A side effect of insulin is low blood sugar, called hypoglycemia.

Weight-loss surgery

Weight-loss surgery changes the shape of the digestive system and how it works. This surgery may help you lose weight and manage type 2 diabetes and other conditions linked to obesity.

There are a few surgical procedures. All of them help people lose weight by limiting how much food they can eat. Some procedures also limit the amount of nutrients the body can absorb.

Weight-loss surgery is only one part of an overall treatment plan. Treatment also includes diet and nutritional supplements, exercise and mental health care.

Weight-loss surgery may be a choice for adults living with type 2 diabetes who have a body mass index (BMI) of 35 or higher. BMI is a formula that uses weight and height to estimate body fat. Surgery also may be a choice for someone with a BMI lower than 35. This depends on how bad the diabetes is or whether there are other medical conditions.

If you have weight-loss surgery, you need to make lifestyle changes for life. Long-term side effects may include not taking in enough nutrients and the bone-loss condition, osteoporosis.

Pregnancy

People who have type 2 diabetes often need to change their treatment plan during pregnancy and follow a diet that controls carbohydrates. Many people need insulin therapy during pregnancy. They also may need to stop other treatments, such as certain blood pressure medicines.

You have a higher risk during pregnancy of getting a condition that affects the eyes, called diabetic retinopathy. This condition may get worse during pregnancy.

If you're pregnant, visit a specialist in eye care, called an ophthalmologist. Go each trimester of your pregnancy and one year after you give birth. Or go as often as your healthcare team advises.

Signs of trouble

You need to track your blood sugar levels to keep from getting serious complications. Also, know of symptoms that may mean that blood sugar levels need care right away. They include:

High blood sugar. This condition also is called hyperglycemia. Eating certain foods or too much food, being sick, or not taking diabetes medicines at the right time can cause high blood sugar. Symptoms include:

  • Urinating often.
  • Extreme thirst.
  • Dry mouth.
  • Blurred vision.
  • Tiredness.
  • Headache.

Hyperglycemic hyperosmolar nonketotic syndrome. Also called HHNS, this life-threatening condition includes a blood sugar reading higher than 600 mg/dL (33.3 mmol/L). HHNS may be more likely if you have an infection, don't take medicines as prescribed, or take certain steroids or other medicines that cause you to urinate often. Symptoms include:

  • Dry mouth.
  • Extreme thirst.
  • Drowsiness.
  • Confusion.
  • Dark urine.
  • Seizures.

Diabetic ketoacidosis. Diabetic ketoacidosis happens when a lack of insulin results in the body breaking down fat for fuel rather than sugar. This causes a buildup of acids called ketones in the bloodstream.

Triggers of diabetic ketoacidosis include certain illnesses, pregnancy and medicines. The diabetes medicines called SGLT2 inhibitors can increase the risk of diabetic ketoacidosis, especially when used in people living with type 1 diabetes.

Diabetic ketoacidosis makes acids that are toxic. So the condition can be life-threatening. Besides the symptoms of hyperglycemia, such as urinating often and more thirst, ketoacidosis may cause:

  • Nausea.
  • Vomiting.
  • Belly pain.
  • Shortness of breath.
  • Fruity-smelling breath.

Low blood sugar. Low blood sugar is when blood sugar levels drop below the target range. This condition also is called hypoglycemia. Your blood sugar level can drop for many reasons. These include missing a meal, taking more medicine than usual or being more physically active than usual. Symptoms include:

  • Sweating.
  • Shakiness.
  • Weakness.
  • Hunger.
  • Irritability.
  • Dizziness.
  • Headache.
  • Blurred vision.
  • Heart palpitations.
  • Slurred speech.
  • Drowsiness.
  • Confusion.

If you have symptoms of low blood sugar, drink or eat something that raises your blood sugar level quickly. Try fruit juice, sugared soda, glucose tablets, hard candy or another source of sugar. Retest your blood in 15 minutes.

If levels are not at your target, eat or drink another source of sugar. Eat a meal after your blood sugar level returns to normal.

If you pass out, someone needs to give you a shot of glucagon. This hormone causes the release of sugar into the blood.

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Lifestyle and home remedies

Careful management of type 2 diabetes can lower the risk of serious, or even life-threatening complications. Try these tips:

  • Commit to managing your diabetes. Learn all you can about type 2 diabetes. Make healthy eating and physical activity part of your daily routine.
  • Work with your team. Connect with a certified diabetes education specialist. Ask your diabetes treatment team for help when you need it.
  • Let others know. Wear a necklace or bracelet that says you have diabetes. This is most important if you take insulin or other blood sugar-lowering medicine.
  • Schedule a yearly physical exam and regular eye exams. Your diabetes checkups aren't meant to replace regular physicals or routine eye exams.
  • Keep your vaccinations up to date. High blood sugar can weaken your immune system. Get a flu shot every year. Stay current on COVID-19 vaccines. Your healthcare team also may suggest the pneumonia vaccine.

    The Centers for Disease Control and Prevention (CDC) also suggests the hepatitis B vaccination if you haven't had this vaccine and you're 19 to 59 years old. Talk to your healthcare team about other vaccinations you may need.

  • Take care of your teeth. Diabetes may make you more likely to get serious gum infections. Brush and floss your teeth regularly and schedule regular dental exams. Contact your dentist right away if your gums bleed or look red or swollen.
  • Watch your feet. Wash your feet daily in lukewarm water. Dry them gently, including between the toes. Use lotion to moisturize them.

    Check your feet every day for blisters, cuts, sores, changes in color and swelling. Contact your healthcare team if you have a sore or other foot problem that isn't healing.

  • Manage your blood pressure and cholesterol. Eating healthy foods and exercising regularly can go a long way toward managing high blood pressure and cholesterol. Take medicines as prescribed.
  • Don't use tobacco products. If you smoke or use other types of tobacco, ask your healthcare team to help you quit. Smoking raises the risk of diabetes complications.
  • Use alcohol sparingly. Drinks with alcohol may lower or raise blood sugar levels. If you choose to drink alcohol, do so only with a meal.

    Drink in moderation. That means no more than one drink daily for people assigned female at birth and no more than two drinks daily for people assigned male at birth. Check your blood sugar often after drinking alcohol.

  • Get good sleep. Many people with type 2 diabetes have sleep problems. Not getting enough sleep may make it harder to keep blood sugar levels in a healthy range. If you have trouble sleeping, talk with your healthcare team about ways to sleep better.

Alternative medicine

Many alternative medicine treatments claim to help people living with diabetes. The National Center for Complementary and Integrative Health says studies haven't shown enough proof for any alternative therapies to manage blood sugar. Research has shown the following results about popular supplements for type 2 diabetes:

  • Chromium supplements have been shown to help little to none. Large doses can cause kidney damage, muscle problems and skin reactions.
  • Magnesium supplements have been shown to help with blood sugar management in some but not all studies. Side effects include diarrhea and cramping. Doses of more than 5,000 mg a day can be fatal.
  • Cinnamon, in some studies, has lowered fasting glucose levels but not A1C levels. So there's no proof that cinnamon improves blood sugar management overall.

Talk with your healthcare team before using a dietary supplement or natural treatment. Don't use alternative medicines in place of your prescribed diabetes medicines.

Coping and support

Type 2 diabetes is a serious disease. Following a diabetes treatment plan can be hard. To manage diabetes well, you may need a good support network.

Anxiety and depression are common in people living with diabetes. Talking to a counselor or therapist may help you cope with the lifestyle changes you need to make and the stress that comes with a type 2 diabetes diagnosis.

Support groups can be good sources of diabetes education, emotional support and helpful information. You might learn how to find local resources or where to find carbohydrate counts for a favorite restaurant. If you want to join a support group, your healthcare team may be able to suggest a group in your area.

Visit the American Diabetes Association website to find local activities and support groups for people with type 2 diabetes. The American Diabetes Association also offers online information and online forums where you can chat with others who are living with diabetes. You also can call the organization at 800-DIABETES (800-342-2383).

Preparing for your appointment

Your annual wellness visit can include screening for diabetes. And it can include watching for and treating conditions that raise your risk of diabetes. These include high blood pressure, high cholesterol or a high BMI.

If you have symptoms that may be linked to diabetes, be ready to answer the following questions at your visit:

  • When did your symptoms begin?
  • Does anything make the symptoms better or worse?
  • What medicines do you take, including dietary supplements and herbal remedies?
  • What do you eat in a typical day? Do you eat between meals or before bedtime?
  • How much alcohol do you drink?
  • How much daily exercise do you get?
  • Is there a history of diabetes in your family?

If you are diagnosed with diabetes, your healthcare professional may begin a treatment plan. Or you may be sent to a specialist in hormonal disorders, called an endocrinologist. Your care team also may include the following specialists:

  • Dietitian.
  • Certified diabetes education specialist.
  • Foot doctor, also called a podiatrist.
  • Specialist in eye care, called an ophthalmologist.

Talk with your healthcare professional about other specialists you might need.

Questions for ongoing appointments

Anytime you see a member of your treatment team, ask if there's anything you need to do before the appointment. These may include not eating or drinking before a test. Always talk about the following with your healthcare team:

  • How often do I need to check my blood sugar? What is my target range?
  • What changes in my diet would help me better manage my blood sugar?
  • What is the right dosage for medicines you prescribe?
  • When do I take the medicines? Do I take them with food?
  • How does managing my diabetes affect treatments for other conditions? How can I make sure treatments work together?
  • When do I need to make a follow-up appointment?
  • When should I call you or seek emergency care?
  • Are there brochures or online sources you suggest?
  • Is there help if I'm having trouble paying for diabetes supplies?

What to expect from your doctor

Your healthcare team might ask you questions at your appointments, such as:

  • Do you know your treatment plan and feel that you can follow it?
  • How are you coping with diabetes?
  • Have you had any low blood sugar?
  • What do you do if your blood sugar is too low or too high?
  • What do you most often eat in a day?
  • Do you exercise? What type of exercise? How often?
  • Do you sit for long periods of time?
  • What makes managing your diabetes hard for you?
Feb. 27, 2025
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