- Insulin Resistance:
- The most common underlying cause. Cells in muscles, fat, and liver become less responsive to insulin, meaning they don't absorb glucose from the blood as effectively.
- To compensate, the pancreas initially produces more insulin, but over time, it may not be able to keep up, leading to elevated blood sugar.
- Decreased Insulin Production:
- The pancreas may not produce enough insulin to manage the body's glucose load, especially during periods of insulin resistance.
- Genetics:
- A family history of Type 2 diabetes or prediabetes significantly increases your risk of IFG.
- Certain genetic predispositions can affect how the body produces or uses insulin.
- Lifestyle Factors:
- Obesity and Overweight: Especially excess abdominal fat, is a major risk factor for insulin resistance.
- Physical Inactivity: Lack of regular exercise contributes to insulin resistance.
- Unhealthy Diet: High intake of refined carbohydrates, sugary drinks, and unhealthy fats can contribute to insulin resistance and weight gain.
- Age: The risk of IFG increases with age, particularly after 45.
- Ethnicity: Certain ethnic groups have a higher prevalence of IFG and Type 2 diabetes.
- Gestational Diabetes History: Women who had gestational diabetes during pregnancy have an increased risk of developing IFG and Type 2 diabetes later.
- Polycystic Ovary Syndrome (PCOS): A common hormonal disorder in women that often involves insulin resistance.
- Sleep Apnea.
- Certain Medications: Such as corticosteroids, some diuretics, and atypical antipsychotics.
- No Symptoms: Most people with IFG are asymptomatic.
- Subtle Symptoms (if any, may indicate progression to Type 2 Diabetes):
- Increased thirst.
- Frequent urination.
- Increased hunger.
- Blurred vision.
- Fatigue.
- Slow-healing sores.
- Numbness or tingling in the hands or feet.
- Acanthosis Nigricans: Darkening and thickening of the skin, especially in the armpits, neck, or groin, can be a sign of insulin resistance.
- Fasting Plasma Glucose (FPG) Test:
- Measures blood glucose after an overnight fast of at least 8 hours (usually 8-12 hours).
- Diagnosis of IFG: A fasting blood glucose level between 100 mg/dL (5.6 mmol/L) and 125 mg/dL (6.9 mmol/L).
- Normal fasting glucose is less than 100 mg/dL.
- Diabetes is diagnosed at 126 mg/dL (7.0 mmol/L) or higher on two separate tests.
- Oral Glucose Tolerance Test (OGTT):
- While FPG is specific to IFG, an OGTT measures blood glucose before and 2 hours after drinking a glucose-containing beverage.
- Diagnosis of Impaired Glucose Tolerance (IGT - another form of prediabetes): A 2-hour blood glucose level between 140 mg/dL (7.8 mmol/L) and 199 mg/dL (11.0 mmol/L).
- A1C Test (Glycated Hemoglobin Test):
- Measures your average blood sugar level over the past 2-3 months.
- Diagnosis of Prediabetes: An A1C level between 5.7% and 6.4%.
- Normal A1C is below 5.7%. Diabetes is diagnosed at 6.5% or higher on two separate tests.
- This test is not a fasting test.
- Risk Factor Assessment: Doctors also consider risk factors like age, weight, family history, and lifestyle during diagnosis.
- Lifestyle Modifications (Cornerstone of Treatment):
- Weight Management: Losing even 5-10% of body weight can significantly improve insulin sensitivity and reduce the risk of Type 2 diabetes.
- Healthy Eating:
- Focus on a balanced diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats.
- Limit processed foods, sugary drinks, refined carbohydrates, and unhealthy fats.
- Portion control.
- Regular Physical Activity: Aim for at least 150 minutes of moderate-intensity aerobic exercise (e.g., brisk walking) per week, plus strength training exercises 2-3 times a week.
- Smoking Cessation: Quitting smoking improves overall health and reduces diabetes risk.
- Limit Alcohol Consumption.
- Medications (May be considered for high-risk individuals):
- Metformin:
- May be prescribed for some high-risk individuals with IFG, especially those who are obese, have a history of gestational diabetes, or have rapidly progressing IFG despite lifestyle changes.
- It works by reducing glucose production by the liver and improving insulin sensitivity.
- Metformin:
- Regular Monitoring:
- Regular follow-up blood tests (e.g., FPG or A1C) are essential to monitor blood sugar levels and assess whether the condition is progressing to Type 2 diabetes or improving.
- Annual screening for Type 2 diabetes is generally recommended for individuals with IFG.