Normal blood glucose is from 70 to 115 mg/dL, and your body has methods for keeping levels within this range even after meals containing high amounts of sugar. Excess sugar in the blood, also known as hyperglycemia, may occur for a brief period following a high carbohydrate meal. If recurring or prolonged, however, hyperglycemia is more likely to be seen in conditions in which your body's regulation mechanisms are impaired, the most common of which is diabetes. Hyperglycemia has certain defining symptoms and if uncontrolled can pose significant health risks.
Most Common Cause
Hyperglycemia is most commonly found in the setting of inadequately controlled diabetes mellitus. Diabetes mellitus is a syndrome with disordered metabolism and inappropriate hyperglycemia due to either a deficiency of the hormone insulin or a resistance to this hormone. Type 1 diabetes is due to injury to the pancreas, insulin's source, while type 2 diabetes most commonly affects overweight individuals and is associated with insulin resistance. Diabetes is diagnosed with a blood sugar level of 126 mg/dL or higher after an overnight fast, documented on more than one occasion.
Other Causes
It is not uncommon in hyperglycemia for blood sugar levels to reach 200 mg/dL or much higher. Conditions other than diabetes that can cause hyperglycemia frequently involve the liver, muscle or fat. These tissues are sensitive to insulin and damage to them can diminish insulin's effect and cause blood sugar to rise. Other causes include hormonal abnormalities such as Cushing syndrome, and medications, most commonly corticosteroids.
Signs and Symptoms
Symptoms of hyperglycemia include polyuria and polydipsia, or excessive urination accompanied by excessive thirst. Weight loss may also occur, especially in the setting of diabetes. Insulin allows your cells to absorb sugar, and when its production or use is impaired, your body is unable to use this valuable source of energy, regardless of how much food you take in. High blood sugar is also associated with high blood pressure and elevated triglycerides in the blood. These conditions are serious in themselves.
Severe Symptoms
If uncontrolled, diabetes mellitus can be life-threatening. Excessive sugar in the blood damages blood vessels, especially those of the eyes and kidneys, in addition to the nerves. This can lead to blindness, kidney failure and loss of sensation in the feet. In severe cases, blood sugar levels can exceed 1000 mg/dL, and confusion, stupor and coma may result.
Considerations
In order to address high blood sugar, it is important to know the cause. In the case of diabetes, a well-balanced, nutritious diet remains a fundamental element of therapy, according to "Current Medical Diagnosis and Treatment, 2011." This involves limiting dietary carbohydrates and cholesterol, and increasing fiber intake. Before starting any new diet or treatment, or if you suffer any of the symptoms of hyperglycemia, talk to your health care professional.
References
- "Current Medical Diagnosis and Treatment"; Stephen J. McPhee; 2011
- "Pathologic Basis of Disease"; Vinay Kumar, M.D.; 2005
- "Biochemistry"; Pamela C. Champe et al.; 2005
