FAMILY MEDICINE® COLUMN

By Martha A. Simpson, D.O., M.B.A.
Assistant Professor of Family Medicine
Ohio University College of Osteopathic Medicine

LOW BLOOD SUGAR NOT NECESSARILY "HYPOGLYCEMIA"

Question: I’m a 58-year-old man, and my family doctor recently asked me to have several blood screening tests. All of my results were in the normal range for my age, except for my glucose level, which was 62. This number was slightly below the 70-106 normal range on the printout. My doctor didn’t seem too concerned. He asked if I had had any “low sugar spells,” including “dizziness” or “disorientation.” When my answer was no, he said he’d just like to check it again in about a year from now. My questions are: What’s the significance of a below normal glucose level? Does this mean I’m hypoglycemic? Since I’m about 30 pounds overweight, would it help to go on a diet? 

Answer: Glucose is the form of sugar your body uses as fuel. Consequently, the terms blood sugar and blood glucose are used interchangeably. The carbohydrates we eat are the primary source of glucose, but the body can convert proteins and fats into glucose, too. When extra glucose is available, it is stored in the liver and muscles for energy needed between meals, and really excessive amounts are converted to fat for longer-term storage.

The body functions best with a blood glucose level between 70 and 106 mg/dl. When the energy demands to run your heart, lungs, brain and muscles are greater than the immediate supply of glucose, the blood level of glucose drops. Usually the liver manufactures more from its stores to keep the blood level within safe bounds, but it isn’t always able to do so. When this happens the blood glucose level drops. When it falls below 70 the label of hypoglycemia “may” be appropriate. Why the wiggle word “may?” Well, fasting hypoglycemia is generally considered to be a blood sugar below 60. Some sources even consider a fasting blood sugar above 50 to be acceptable. You see, the diagnosis of hypoglycemia requires more that just the blood sugar value when it is between 50 and 70. Other symptoms must be considered, too. Symptoms of low blood sugar can be hunger, nervousness, dizziness, sleepiness, confusion or difficulty speaking.

This is an uncommon problem except in diabetics. In a non-diabetic person, a low fasting blood sugar can be a signal of an underlying medical problem or an undesired side effect of prescription or over-the-counter medicines. Even aspirin can cause your blood glucose levels to drop, though rarely.
Binge drinking of alcohol can damage the liver and interfere with glucose storage, thus causing hypoglycemia. Starvation and serious systemic illness can also cause episodes of low blood sugar. Also, an insulin producing tumor can cause hypoglycemia, but fortunately, these are quite rare.

You apparently don’t have these symptoms since your doctor wasn’t particularly concerned. I’m sure he or she suggested you follow a balanced diet and avoiding prolonged periods of fasting (eat three meals each day). It is always a good idea from a health standpoint to get your weight close to the ideal level.

Family Medicine® is a weekly column. To submit questions, write to Martha A. Simpson, D.O., M.B.A., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701. Medical information in this column is provided as an educational service only. It does not replace the judgment of your personal physician, who should be relied on to diagnosis and recommend treatment for any medical conditions. Past columns are available online at http://www.FamilyMedicineNews.org.