Normal Blood Glucose Levels

Glucose Level Indications: Normal, Prediabetes And Diabetes

What Is The Normal Blood Glucose Level?

Normal blood glucose levels are essential for the optimum functioning of all the organs of the body. Any alterations, whether increased or decreased glucose level may lead to various conditions. Normal blood glucose level depends upon various factors and thus have different values. Time of the day and the meals commonly affect the glucose levels. The fasting normal blood glucose level should be less than 100 mg/dl for people who are non-diabetic and should have a target range of 70-130 mg/dl in patients with diabetes. Feeding blood glucose level, i.e. two hours after a meal should be less than 140 mg/dl in non-diabetics and less than 180 mg/dl for non-diabetics.

Normal And Altered Sugar Levels

Test Normal Prediabetic Diabetic
HBA1C (%) < 5.7 5.7 to 6.4 > 6.4
Fasting Glucose Level (mg/dl) < 100 100-125 > 125
OGTT (mg/dl) < 140 140-199 > 199

What Are Prediabetes And Diabetes?

Prediabetes is considered a warning sign that you are at high risk of developing diabetes in the future. Progression of prediabetes to diabetes can be delayed or prevented by modifying lifestyle and increasing physical activity. If the fasting glucose is in the range of 100 -125 mg/dl, you are suffering from prediabetes or impaired fasting glucose.

Diabetes is the condition diagnosed when the fasting plasma glucose level is greater than 125 mg/dl. The HBA1C in such patients is 6.5% or higher. Diabetes may be type 1 diabetes or type 2 diabetes.

What Is Hypoglycemia?

Hypoglycemia is a condition characterized by low glucose levels in the blood. For diabetic patients, the level below 70 mg/dl is considered hypoglycemia. In non-diabetics, hypoglycemia is diagnosed based on symptoms and improvement in symptoms after normalizing the glucose levels. In general cases, a glucose level of less than 50 mg/dl is considered hypoglycemic when measured without eating or performing any physical activity.

What Are The Various Causes Of Increased Glucose Levels?

There are various causes of increased glucose levels. Some of the causes are;

  • Autoimmune disease in which the immune system attacks he pancreatic cells responsible for secreting insulin. This is seen in Type 1 diabetes.
  • Gestational diabetes i.e. diabetes during pregnancy.
  • Cystic fibrosis
  • Medications such as steroids and beta-blockers.
  • Infection
  • Stress

What Are The Various Symptoms Of High Blood Glucose Levels?

Following are the various symptoms of high glucose levels;

  • Frequent urination to remove excess sugar.
  • The frequent thirst to dilute the high glucose level and to make up for the volume used due to excess urination.
  • Increased time for wound healing
  • Fatigue
  • Bloating
  • Reduced concentration
  • Dry mouth
  • Blurred vision

What Are The Various Symptoms Of Low Glucose Level In Blood?

Low blood sugar significantly affects the functioning of the central nervous system.

Following are the various symptoms of low glucose levels;

  • Feeling of numbness
  • Headache
  • Seizures
  • Blurred vision
  • Coma and stupor
  • Difficulty breathing
  • Fatigue and weakness
  • Dementia, confusion, lack of concentration
  • Impaired judgment and depression

What Are The Complications Of Increased Glucose Levels?

Increased glucose levels, if not treated, may lead to serious complications. These complications may include;

Progression To Diabetes

If the glucose levels are not controlled in the prediabetic stage, there is a high risk of transforming it into diabetes.

Diabetic Neuropathy

High glucose level damages the nerve cells especially in the extremities such as hands and legs.

Diabetic Nephropathy

In prolonged uncontrolled diabetes, renal damage may occur.

Diabetic Retinopathy

High glucose levels may damage the cells of retina leading to vision problems.


In diabetic patients, wounds are difficult to treat and, in many cases, foot amputation is required.

Skin Conditions

People with diabetes are prone to fungal and bacterial infections of the skin.

Neurological Disorders

High glucose levels may lead to various neurological disorders such as depression or Alzheimer’s disease.

What Are The Complications Of Reduced Glucose Levels?

It is extremely essential to treat low glucose levels as this may lead to life-threatening complications. These complications include;

  • Slurred speech
  • Loss of consciousness
  • Coma
  • Death
  • Seizures
  • Hypoglycemia may also lead to vehicle accidents and falls leading to serious injuries.

How Glucose Levels Are Determined?

There are various methods to evaluate Glucose levels;

1. HBA1C

HBA1C is the measure of blood glucose level which indicates average reading of the past 2-3 months. As the glucose level of blood rises, it gets attached to the hemoglobin. The glucose attached to hemoglobin levels is then measured. The normal level of HBA1C is less than 5.7%.

2. Fasting Blood Glucose

The main requirement for fasting blood glucose is that the person should not eat or drink anything for at least 8 hours before having this test. The blood is drawn and analyzed for sugar.

3. Oral Glucose Tolerance Test (OGTT)

In this test, the sugar levels are measured before and 2 hours after the person drinks a sweet drink of appropriate concentration.

What Are The Treatment Options For Altered Glucose Levels?

Following are the various treatment options for maintaining normal blood glucose levels;

  • Exercise and increased physical activity
  • Control over diet
  • Oral Medications
  • Insulin injections