Glucose is the main type of sugar in the blood and the primary source of energy for the body’s cells. It is derived from carbohydrate-containing foods, enters the bloodstream after digestion, and is then used by the cells as fuel. Fluctuations in glucose levels — whether increases or decreases — can disrupt the body’s balance. Over time, these imbalances may contribute to health problems such as obesity, diabetes, and cognitive impairment.
How is Glucose Measured?
Glucose levels are typically checked with a fasting blood glucose test, performed after at least 8 hours of fasting. The measurement can be done with a finger-prick blood sample using a glucometer or in a laboratory setting.The HbA1c test evaluates long-term blood glucose control by showing the average glucose level over the past 2–3 months. It is used to assess the risk of diabetes:
-
Normal: below 5.7%
-
Prediabetes: 5.7–6.4%
-
Diabetes: 6.5% or higher
What Should Glucose Levels Be?
-
Fasting: 70–100 mg/dL
-
Postprandial (after meals): 70–140 mg/dL
-
Below 60 mg/dL: Hypoglycemia
-
Above 130 mg/dL (fasting) / 180 mg/dL (postprandial): Hyperglycemia
What is Hypoglycemia (Low Blood Glucose)?
Hypoglycemia is defined as blood glucose falling below 60 mg/dL. It is most commonly seen in patients with type 1 diabetes or those using insulin or certain medications.Symptoms may include:
-
Intense hunger
-
Fatigue, weakness
-
Dizziness
-
Irritability
-
Palpitations
-
Blurred vision
-
Sweating, trembling
-
Difficulty speaking
-
Anxiety
Main causes: Excessive insulin use, inadequate caloric intake, prolonged exercise, or certain medical conditions.
What is Hyperglycemia (High Blood Glucose)?
Hyperglycemia occurs when blood glucose levels rise above normal. It is defined as fasting blood glucose over 130 mg/dL or postprandial glucose over 180 mg/dL.Symptoms may include:
-
Excessive thirst and frequent urination
-
Headache, blurred vision
-
Fatigue, unexplained weight loss
-
Recurrent infections
-
Delayed wound healing
Causes: Insufficient insulin, poor diabetes control, unbalanced diet, or lack of physical activity.
How is High Blood Glucose Treated?
In patients with diabetes, treatment may include insulin or oral medications. In addition, glucose levels can be stabilized by:-
Consuming low-glycemic index foods
-
Reducing sugar intake
-
Increasing physical activity
-
Drinking sufficient water
-
Eating fiber-rich foods
-
Consuming magnesium-rich foods
-
Managing stress
-
Ensuring adequate, high-quality sleep
-
Limiting caffeine and alcohol
Frequently Asked Questions
-
Is glucose the same as dextrose?
In common use, “glucose” refers to blood sugar, while “dextrose” is the general chemical name. -
What does negative glucose in urine mean?
A negative glucose result in urine is usually normal and indicates that blood glucose is not excessively high. -
What is impaired fasting glucose?
A fasting glucose between 100–125 mg/dL is considered prediabetes. -
What is a glucose tolerance test?
Often performed during pregnancy, this test evaluates the body’s response to glucose after fasting, followed by a glucose load.
Why Balanced Glucose Matters
Maintaining stable glucose levels is essential for reducing the risk of diabetes and for healthy weight management. Obesity and insulin resistance are key factors that directly affect glucose metabolism. Excess weight decreases the body’s sensitivity to insulin, leading to unstable blood sugar. For individuals struggling with obesity-related health problems and unsuccessful weight management, surgical options may be considered. In Turkey, procedures such as gastric sleeve surgery, which is also covered by the national insurance (SGK) in certain cases, have shown effective results in both weight reduction and blood glucose control.
