Symptoms & Diagnosis

Many people who have diabetes don’t know it yet. In fact, it can take years for people with Type 2 diabetes to recognize signs or symptoms. That’s why you should know the warning signs and how doctors test for it.

Signs and symptoms of Type 2 diabetes often develop slowly. In fact, you can have Type 2 diabetes for years and not know it. Look for:

  • Increased thirst and frequent urination. Excess sugar building up in your bloodstream causes fluid to be pulled from the tissues. This may leave you thirsty. As a result, you may drink — and urinate — more than usual.
  • Increased hunger. Without enough insulin to move sugar into your cells, your muscles and organs become depleted of energy. This triggers intense hunger.
  • Weight loss. Despite eating more than usual to relieve hunger, you may lose weight. Without the ability to metabolize glucose, the body uses alternative fuels stored in muscle and fat. Calories are lost as excess glucose is released in the urine.
  • Fatigue. If your cells are deprived of sugar, you may become tired and irritable.
  • Blurred vision. If your blood sugar is too high, fluid may be pulled from the lenses of your eyes. This may affect your ability to focus.
  • Slow-healing sores or frequent infections. Type 2 diabetes affects your ability to heal and resist infections.
  • Areas of darkened skin. Some people with Type 2 diabetes have patches of dark, velvety skin in the folds and creases of their bodies — usually in the armpits and neck. This condition, called acanthosis nigricans, may be a sign of insulin resistance.

When to see a doctor

See your doctor if you notice any Type 2 diabetes symptoms.

Diagnosis

To diagnose Type 2 diabetes, you'll be given a:

  • Glycated hemoglobin (A1C) test. This blood test indicates your average blood sugar level for the past two to three months. It measures the percentage of blood sugar attached to hemoglobin, the oxygen-carrying protein in red blood cells. The higher your blood sugar levels, the more hemoglobin you'll have with sugar attached. An A1C level of 6.5 percent or higher on two separate tests indicates you have diabetes. A result between 5.7 and 6.4 percent is considered prediabetes, which indicates a high risk of developing diabetes. Normal levels are below 5.7 percent.
  • If the A1C test isn't available, or if you have certain conditions — such as if you're pregnant or have an uncommon form of hemoglobin (known as a hemoglobin variant) — that can make the A1C test inaccurate, your doctor may use the following tests to diagnose diabetes:
  • Random blood sugar test. A blood sample will be taken at a random time. Blood sugar values are expressed in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). Regardless of when you last ate, a random blood sugar level of 200 mg/dL (11.1 mmol/L) or higher suggests diabetes, especially when coupled with any of the signs and symptoms of diabetes, such as frequent urination and extreme thirst.
  • Fasting blood sugar test. A blood sample will be taken after an overnight fast. A fasting blood sugar level less than 100 mg/dL (5.6 mmol/L) is normal. A fasting blood sugar level from 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is considered prediabetes. If it's 126 mg/dL (7 mmol/L) or higher on two separate tests, you have diabetes.
  • Oral glucose tolerance test. For this test, you fast overnight, and the fasting blood sugar level is measured. Then you drink a sugary liquid, and blood sugar levels are tested periodically for the next two hours.
  • A blood sugar level less than 140 mg/dL (7.8 mmol/L) is normal. A reading between 140 and 199 mg/dL (7.8 mmol/L and 11.0 mmol/L) indicates prediabetes. A reading of 200 mg/dL (11.1 mmol/L) or higher after two hours may indicate diabetes.

The American Diabetes Association recommends routine screening for Type 2 diabetes beginning at age 45, especially if you're overweight. If the results are normal, repeat the test every three years. If the results are borderline, ask your doctor when to come back for another test.

Screening is also recommended for people who are under 45 and overweight if there are other heart disease or diabetes risk factors present, such as a sedentary lifestyle, a family history of Type 2 diabetes, a personal history of gestational diabetes or blood pressure above 140/90 millimeters of mercury (mm Hg).

If you're diagnosed with diabetes, the doctor may do other tests to distinguish between Type 1 and Type 2 diabetes — since the two conditions often require different treatments.

After the diagnosis

A1C levels need to be checked between two and four times a year. Your target A1C goal may vary depending on your age and other factors. However, for most people, the American Diabetes Association recommends an A1C level below 7 percent. Ask your doctor what your A1C target is.

Compared with repeated daily blood sugar tests, the A1C test is a better indicator of how well your diabetes treatment plan is working. An elevated A1C level may signal the need for a change in your medication, meal plan or activity level.

In addition to the A1C test, your doctor will take blood and urine samples periodically to check your cholesterol levels, thyroid function, liver function and kidney function. The doctor will also assess your blood pressure. Regular eye and foot exams also are important.

Preparing for an appointment

Your primary care doctor will probably diagnose your Type 2 diabetes. He or she may continue to treat your diabetes or may refer you to a doctor who specializes in hormonal disorders (endocrinologist). Your health care team also may include:

  • Dietitian
  • Certified diabetes educator
  • Foot doctor (podiatrist)
  • Doctor who specializes in eye care (ophthalmologist)

If your blood sugar levels are very high, your doctor may send you to the hospital for treatment.

Whenever you can, it's a good idea to prepare for appointments with your health care team. Here's some information to help you get ready for your appointment and know what to expect from your doctor.

What you can do

  • Be aware of any pre-appointment restrictions. You may need to refrain from eating or drinking anything but water for eight hours for a fasting glucose test or four hours for a pre-meal test. When you're making an appointment, ask if you should fast.
  • Write down any symptoms you're experiencing, including any that may seem unrelated to your diabetes.
  • Bring a notebook and a pen or pencil (or your laptop computer or tablet) to keep track of important information.
  • Write down questions to ask your doctor.

Preparing a list of questions can help you make the most of your time with your doctor. For Type 2 diabetes, some basic questions to ask include:

Glucose monitoring

  • How often do I need to monitor my blood sugar?
  • What is my goal range?
  • How can I use the information from glucose monitoring to better manage my diabetes?

Lifestyle changes

  • What changes do I need to make to my diet?
  • How can I learn about counting carbohydrates in foods?
  • Should I see a dietitian to help with meal planning?
  • How much exercise should I get each day?

Medications

  • Will I need to take medicine? If so, what kind and how much?
  • Do I need to take the medicine at a particular time of the day?
  • Do I need to take insulin?
  • I have other medical problems. How can I best manage these conditions together?

Complications

  • What are the signs and symptoms of low blood sugar?
  • How do I treat low blood sugar?
  • What are the signs and symptoms of high blood sugar?
  • When should I test for ketones, and how do I do it?

Medical management

  • How often do I need to be monitored for diabetes complications? What specialists do I need to see?
  • Are there resources available if I'm having trouble paying for diabetes supplies?
  • Are there brochures or other printed material that I can take with me? What websites do you recommend?

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

  • Do you understand your treatment plan and feel confident you can follow it?
  • How are you coping with diabetes?
  • Have you experienced any low blood sugar?
  • What's a typical day's diet like?
  • Are you exercising? If so, what type of exercise? How often?
  • What challenges are you experiencing in managing your diabetes?

What you can do in the meantime

If your blood sugar is consistently out of your target range, or if you're not sure what to do in a certain situation, contact your doctor or diabetes educator.

This article is from the Mayo Clinic Health Information Library and is legally licensed through the NewsCred publisher network. Please direct all licensing questions to legal@newscred.com.

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Prevention

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Symptoms & Diagnosis

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Complications

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Treatment

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Coping & Support

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