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Why Your Healthcare Provider Tests Your Blood Sugar

may contain hands checking blood sugar

In adults, a screening blood sugar test is generally used to see whether blood sugar is too high. Often adults with raised blood sugar don’t have obvious symptoms of diabetes or prediabetes. Finding and treating type 2 diabetes early is important to prevent problems that it can cause.

Type 2 on the rise

Type 2 diabetes is on the increase in the U.S. This rise can be controlled if more people pay attention to lifestyle choices. Americans eat too much and exercise too little. Some long-term damage to the body may already be occurring in prediabetes. This is especially true for the heart and circulatory system. People with prediabetes are at high risk of developing type 2 diabetes. Studies have shown that people with prediabetes can put off getting type 2 diabetes by doing several things. They can make changes in their diet, exercise more, and lose weight.

What is diabetes?

Many people don’t know what type 2 diabetes is or why doctors are interested in their blood sugar levels. The hormone insulin is made by your pancreas. Insulin allows your body to use sugar and other food for energy. Blood sugar rises when you don’t have enough insulin. It also rises when your body’s cells are unable to use what is there.

In type 2 diabetes, your pancreas either does not make enough insulin or your body’s cells aren’t properly using the insulin. This is called insulin resistance. When blood sugar goes up again and again, the risk for heart attack and stroke goes up by up to 4 times. It also greatly raises the risk for kidney disease. You are also at risk for blindness, amputation because of poor circulation, and other disorders.

Type 2 diabetes is usually diagnosed later in life. But in an alarming trend, many teens are being diagnosed with it. This was almost unheard of 20 years ago. This is thought to be directly related to being extremely overweight, having a poor diet, and a lack of exercise. The American Diabetes Association (ADA) recommends type 2 diabetes screening for children and teens who are overweight and have at least 2 of these risk factors:

  • Family history of diabetes
  • Being in a high-risk ethnic group
  • Having signs of insulin resistance

It’s always best to find diabetes before symptoms start. But watch for these symptoms:

  • Extreme tiredness
  • Intense thirst
  • Need to urinate often
  • Sores that don’t heal
  • Weight loss when you aren’t trying to lose weight
  • Tingling or numbness in your feet or hands
  • On-and-off blurry vision

According to the U.S. Preventive Services Task Force, adults who are 40 to 70 years old and are overweight should get screened every 3 years. If you have other risk factors for diabetes, you may need screening tests more often. Regardless of weight, all adults 45 years old and older should be screened for diabetes every 3 years.

Risk factors

Risk factors for type 2 diabetes are:

  • Being older than 45 years
  • Being overweight or obese (body mass index of 25 or higher)
  • Having parents or siblings who have diabetes
  • High blood pressure (140/90 mmHg or higher in adults)
  • HDL (“good’) cholesterol of less than 35 mg/dL, a triglyceride level of 250 mg/dL or higher, or both
  • Getting little exercise
  • High-risk race or ethnicity. This includes African American, Alaska Native, Hispanic American, American Indian, Asian American, and Pacific Islander.
  • Blood sugar test in the past that was high
  • Having polycystic ovarian syndrome (PCOS)
  • Having a history of heart disease

Diagnosing diabetes

The ADA now recommends the A1C test to help diagnose prediabetes and diabetes. The A1C gives an average blood glucose level for the previous 3 months. An A1C level of around 5% is considered normal. An A1C of 6.5% or above shows diabetes.

The A1C test is not more accurate than the fasting plasma glucose test and the 2-hour oral glucose tolerance test. The difference is the AIC test does not require fasting. It can be measured at any time of the day.

Experts hope the ease of the A1C will result in more testing for people who are at risk for diabetes or prediabetes. This would help reduce the number of people with undiagnosed diabetes in the U.S.

Online Medical Reviewer: Fetterman, Anne, RN, BSN 
Online Medical Reviewer: Hurd, Robert, MD 
Online Medical Reviewer: Turley, Raymond Kent, BSN, MSN, RN 

Date Last Reviewed: 12/1/2016 

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