Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention

Definition

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 your 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.

Causes

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

Symptoms

You may have diabetes for years before you have symptoms.

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

Diagnosis

The doctor will ask 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

Treatment aims to:

  • Maintain blood sugar at levels as close to normal as possible
  • Avoid hypoglycemia
  • Prevent or delay complications
  • Control other conditions that you may have, like 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 your blood glucose level. Eating healthy meals can help you control your blood glucose. It will also help your 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 your food to help understand ideal serving size.
  • Do not skip meals. Plan your 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 your foods.
  • Eat moderate amounts of protein and low-fat dairy products.
  • Carefully limit foods containing high concentrated sugar.
  • Keep a record of your food intake. Share the record with your dietitian or doctor. This will help to create an effective meal plan.

If you are overweight, weight loss will help your body use insulin better. Talk to your doctor about a healthy weight goal. You and your doctor or dietitian can make a safe meal plan for you.

These options may help you lose weight:

Physical activity can:

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

Aerobic exercise is any activity that increases your 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 your risk of heart disease.

Aim for ≥ 150 minutes of physical activity each week. Talk to your doctor about an activity plan. Ask about any precautions you may need to take.

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.

If not controlled by diet and exercise, you may need medications to control your blood pressure and cholesterol.

You will need to get all of your vaccinations. Some may be needed earlier in children with diabetes.

You can check the level of glucose in your blood with a blood glucose meter. Checking your blood glucose levels during the day can help you stay on track. It will also help your doctor determine if your treatment is working. Keeping track of blood sugar levels is especially important if you take insulin.

Regular testing may not be needed if your diabetes is under control and you don't take insulin. Talk with your doctor before stopping blood sugar monitoring.

An HbA1c test may also be done at your 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%. Your exact goal may be different. Keeping HbA1c in your goal range can help lower the chance of complications.

Depression can undermine your recovery and put you at risk for other complications. Feelings of sadness, hopelessness, and loss of interest in your favorite activities that stay with you for at least 2 weeks should prompt you to call your doctor. Depression is treatable. Your doctor may refer you to counseling to help you better manage your depression and diabetes.

Complications

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

Diabetes can also increase your risk of heart disease.

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

  • Take good care of your feet. Be on the lookout for any sores or irritated areas. Keep your feet dry and clean.
  • Have your eyes checked once a year.
  • Don't smoke. If you do, look for programs or products that can help you quit.
  • Keep track of your moods and be alert for persistent depressive symptoms.
  • Plan medical visits as recommended.

Prevention

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