Diabetes: The Danger from High Serum Glucose

Talk to your doctor if you have diabetes and can’t keep your blood sugar at a safe level.
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Blood sugar, blood glucose, serum glucose. If you've recently been diagnosed with pre-diabetes or diabetes, you may be overwhelmed with all the terminology. But the bottom line is that, no matter what you call it, a high level of sugar in your blood is dangerous. Here's what else you need to know.


Read more:Why Too High or Too Low Blood Sugar Could Be Dangerous

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Understanding the Danger

"Serum glucose is essentially blood glucose, which is more commonly known as blood sugar," says Minisha Sood, MD, an endocrinologist at Northwell Health's Lenox Hill Hospital in New York City. "Normal blood serum glucose is less than 100 milligrams per deciliter (mg/dL) in the fasting state and less than 140 mg/dL generally in the 'fed' state."

The fed state, also known as the post-absorptive state, occurs after eating a meal, according to the National Library of Medicine. It's when your body digests a meal.

Blood glucose is measured with a blood test. Taken when you're in the fasting state simply means that you haven't eaten anything since the evening before the test, according to the Centers for Disease Control and Prevention (CDC).


Having a glucose level above the normal range means that there is an excess of glucose in the body that is being over-consumed, over-produced and released in excess by the liver, not being taken up by muscle, and being taken back into the bloodstream by the kidneys, explains Dr. Sood. That's bad, she says, because "excess glucose, once above a certain threshold, leads to diabetes."

Other defining characteristics of this type of diabetes, called type 2, include insulin-resistant tissue and a lack of enough insulin to surmount this resistance, according to the Diabetes Teaching Center at the University of California, San Francisco.


Diabetes is not only a chronic condition that needs to be managed, but it can also lead to a host of health problems — from kidney failure to blindness and even the loss of limbs as a result of complications of poor blood flow, according to the CDC. It increases the risk for stroke and heart disease. Diabetes is also financially costly. People with diabetes spend more money on health care and take more days off from work than people who do not have the disease, the CDC notes.



Causes, Signs and Symptoms

Though a blood test to check blood glucose levels is needed to make a diabetes diagnosis, there are warning signs of high blood sugar, according to the University of Iowa Hospitals & Clinics (UIHC). These include:

  • Thirst.
  • Dry mouth.
  • Blurry vision.
  • Weight loss.
  • Frequent urination, including at night.
  • Drowsiness.
  • Increased appetite.


Symptoms of extremely high blood sugar include:

  • Difficulty breathing.
  • Rapid weight loss.
  • Dizziness when standing up.
  • Confusion.
  • Increased tiredness.
  • Loss of consciousness.
  • Nausea or vomiting.

Lowering High Serum Glucose

To manage blood sugar when you have diabetes, the UIHC stresses taking your medications, checking your blood sugar levels and sticking to the meal plan outlined by your doctor, nurse or dietitian.


"Non-starchy vegetables and lean proteins do not raise glucose levels by much and should be the cornerstone of how meals are put together and how blood glucose levels are managed in patients at increased risk for high glucose and diabetes," says Dr. Sood.

There are certain foods you should steer clear of. "All carbohydrates increase blood glucose levels," says Dr. Sood. "Foods that raise glucose levels quickly and unfavorably include those made from refined sugars and flours." Topping the list are:


  • Candy.
  • Soda.
  • Cookies and pastries.
  • Juice.
  • Dried fruit.
  • Cereal.
  • Bread.
  • Pasta.

According to Dr. Sood, it's possible to eat some carbs, but they should be the type that raises glucose levels in a slow, steady manner, like beans, lentils and whole grains, which contain fiber.

You'll also want to watch out for things that things that the UIHC warns can cause your serum glucose levels to rise:

  • Not sticking to your meal plan (eating too much).
  • Not taking diabetes medication.
  • Infection.
  • Illness.
  • Injury.
  • Surgery.
  • Emotional stress.

If you have diabetes and can't keep your blood sugar level in a safe zone, check in with your doctor.

Read more:The Major Causes of Type 2 Diabetes — and Who's Most at Risk




Is this an emergency? If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911.

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