Diabetes Type 2



Glucose is a type of sugar. It comes from food, and is also created in the liver. Glucose travels through the body in the blood. It moves from the blood to cells with the help of a hormone called insulin. Once glucose is in those cells, it can be used for energy. Insulin also helps glucose to move into the liver for storage if there is too much to use.

Diabetes is a condition that makes it difficult for the body to use or store glucose. This causes a buildup of glucose in the blood. It also means the body is not getting enough energy. Type 2 diabetes is one type of diabetes. It is the most common type in adults.

Medication, lifestyle changes, and monitoring can help control blood glucose levels.


Type 2 diabetes is often caused by a combination of factors. The initial factor is that the body becomes resistant to insulin. This means there is insulin in the body, but the body cannot use it effectively. Insulin resistance is often related to excess body fat. A second factor is that the body begins to make less insulin.

Risk Factors

Type 2 diabetes is more common in people who are aged 45 years and older, but can develop in children. It is also common in younger people who are obese and belong to at-risk ethnic groups. Other factors that increase the chance of type 2 diabetes include:

  • Prediabetes—impaired glucose tolerance and impaired fasting glucose
  • Metabolic syndrome—a condition marked by elevated cholesterol, blood glucose, blood pressure, and central obesity
  • Excess weight or obesity, especially central obesity
  • Family history of type 2 diabetes
  • History of gestational diabetes, or having a baby that weighs over 9 pounds at birth
  • Being born small or large for gestational age
  • Certain medications, such as glucocorticoids or thiazides
  • Certain ethnic groups, such as African American, Hispanic, Native American, Hispanic American, Asian American, or Pacific Islander
  • Endocrine disorders, such as Cushing’s syndrome, hyperthyroidism, acromegaly, polycystic ovary syndrome, or acute pancreatitis
  • Conditions associated with insulin resistance, such as acanthosis nigricans
  • Lack of exercise
  • Poor diet—high intake of processed meats, fats, sugar-sweetened foods and beverages, and calories
  • High blood pressure
  • History of cardiovascular disease
  • Depression



Diabetes may be present for years before symptoms occur.

Symptoms caused by high blood sugar include:

  • Increased urination
  • Extreme thirst
  • Hunger
  • Fatigue
  • Blurry vision
  • Irritability

Symptoms caused by chronic hyperglycemia may include

  • Frequent or recurring infections
  • Poor wound healing
  • Numbness or tingling in the hands or feet
  • Problems with gums
  • Itching
  • Problems having an erection
  • Symptoms of heart or kidney disease


You will be asked about your symptoms and medical history. You will also be asked about your family history. A physical exam will be done.

Diagnosis is based on the results of blood testing. American Diabetes Association (ADA) recommends diagnosis be made if you have one of the following:

  • Symptoms of diabetes and a random blood test with a blood sugar level greater than or equal to 200 mg/dL (11.1 mmol/L)
  • Fasting blood sugar test is done after you have not eaten for 8 or more hours—showing blood sugar levels greater than or equal to 126 mg/dL (7 mmol/L) on two different days
  • Glucose tolerance test measures blood sugar 2 hours after you eat glucose—showing glucose levels greater than or equal to 200 mg/dL (11.1 mmol/L)
  • HbA1c level of 6.5% or higher—indicates poor blood sugar control over the past 2-4 months

mg/dL = milligrams per deciliter of blood; mmol/L = millimole per liter of blood

You may also need blood tests to confirm diabetes is type 1 and not type 2. These may include:

  • Insulin level or C-peptide tests—to see how much insulin is being made by the pancreas
  • Tests that look for antibodies that are working against your pancreas

You may also need other tests, including.

  • Cholesterol levels
  • Urine for glucose, ketones, or albumin
  • Liver and kidney function tests in adults



Treatment aims to:

  • Maintain blood sugar at levels as close to normal as possible
  • Avoid hypoglycemia
  • Prevent or delay complications
  • Control other conditions, such as high blood pressure and high cholesterol

Diet, exercise, and weight loss are recommended for all patients. Most patients will also begin medication.


Food and drinks have a direct effect on blood glucose levels. Eating healthy meals can help control blood glucose. It will also promote overall health. Some basic tips include:

  • Follow a balanced meal plan. It should include carbohydrates, proteins, and fats.
  • Be aware of appropriate serving size. Measure food to help understand ideal serving size.
  • Do not skip meals. Plan meals and snacks through the day. Having meals throughout the day can help avoid major changes in glucose levels.
  • Eat plenty of vegetables and fiber.
  • Limit the amount of fat (especially saturated and trans fats) in foods.
  • Eat moderate amounts of protein and low-fat dairy products.
  • Carefully limit foods containing high concentrated sugar.
  • Keep a food intake record. Share the record with the dietitian or doctor. This will help to create an effective meal plan.

Weight Loss

In those who are overweight, weight loss will help the body use insulin better. Talk to the doctor about a healthy weight goal. A safe meal plan can be created.

These options may help with weight loss:

  • Use a portion control plate
  • Use a prepared meal plan
  • Eat a Mediterranean-style diet


Physical activity can:

  • Make the body more sensitive to insulin
  • Help to reach and maintain a healthy weight
  • Lower the levels of fat in the blood

Aerobic exercise is any activity that increases heart rate. Resistance training helps build muscle strength. Both types of exercise help to improve long-term glucose control. Regular exercise can also help reduce the risk of heart disease.

Aim for ≥ 150 minutes of physical activity each week. Talk to the doctor about an activity plan. Ask about any precautions that may be needed.


Non-insulin Glucose Lowering Medication

Medications other than insulin are typically used first to manage blood glucose levels.

Biguanides, usually metformin, are the first choice. They work by reducing the amount of glucose made by the body.

  • Metformin is the only medication approved for use in children.
  • In adults other medications may be added if treatment goals are not met.
    • Medication taken by mouth may include:
      • Sulfonylureas or dipeptidyl peptidase IV (DPP-4) inhibitors to encourage the pancreas to make more insulin
      • Thiazolidinediones which sensitize the body to insulin so it works better at lower amounts
      • Starch blockers to decrease the amount of glucose absorbed into the blood
      • Sodium-glucose co-transporter 2 (SGLT-2) inhibitors to increase glucose excretion in urine
      • Bile acid binders
    • Medications given by injection may include:
      • Glucagon-like peptide-1 receptor agonists (incretin-mimetics) stimulate the pancreas to produce insulin and decrease appetite, which can assist with weight loss
      • Amylin analogs replace a protein of the pancreas that is low in people with type 2 diabetes


Insulin may be needed if:

  • The body does not make enough of its own insulin
  • Blood glucose levels cannot be controlled with lifestyle changes and other medications

Insulin is given through injections. There is one short-acting inhaled insulin which may be effective for select persons.

Other medications

If not controlled by diet and exercise, medications may be used to control blood pressure and cholesterol.

Vaccinations will be needed. Some may be needed earlier in children with diabetes.

Blood Glucose Testing

Check the level of glucose in the blood with a blood glucose meter. Checking blood glucose levels during the day can help with staying on track. It will also help the doctor determine if treatment is working. Keeping track of blood sugar levels is especially important for those taking insulin.

Regular testing may not be needed if diabetes is under control and insulin is not being taken. Talk with the doctor before stopping blood sugar monitoring.

An HbA1c test may also be done at the doctor's office. This is a measure of blood glucose control over a long period of time. Doctors advise that most people keep their HbA1c levels below 7%. Individual goals may be different. Keeping HbA1c in the goal range can help lower the chance of complications.


Depression can undermine recovery and increase the risk of other complications. Feelings of sadness, hopelessness, and loss of interest in activities that last at least 2 weeks require a call to the doctor. Depression is treatable. Counseling can help better manage depression and diabetes.


To help reduce your chance of type 2 diabetes:

  • Participate in regular physical activity
  • Maintain a healthy weight
  • Drink alcohol only in moderation (2 drinks per day for a man, and 1 drink per day for a woman)
  • Eat a well-balanced diet:
    • Get enough fiber
    • Avoid fatty foods
    • Limit sugar intake
    • Eat more green, leafy vegetables
    • Eat whole fruits, especially apples, grapes, and blueberries

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

a (Diabetes Mellitus Type 2; Insulin-Resistant Diabetes; Diabetes, Type 2)


Over a long period of time, high blood glucose levels can damage vital organs. The risk of complications increases with increasingly poor control

Common complications

  • Retinopathy
  • Nephropathy
  • Neuropathy
  • Diabetic foot ulcer

Diabetes can also increase the risk of heart disease.

Decreasing Risk of Complications

Maintaining goal blood glucose and HbA1c levels according to the doctors recommendations is the first step to lowering the risk of these complications. Other steps:

  • Practice good footcare. Be on the lookout for any sores or irritated areas. Keep the feet dry and clean.
  • Get yearly eye exams.
  • Don't smoke. If you do, look for programs or products that can help you quit.
  • Keep track of moods and be alert for persistent depressive symptoms.
  • Plan medical visits as recommended.


American Diabetes Association http://www.diabetes.org 

National Diabetes Information Clearinghouse http://diabetes.niddk.nih.gov 


Canadian Diabetes Association http://www.diabetes.ca 

Public Health Agency of Canada http://www.phac-aspc.gc.ca 


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