1. Introduction
Type 2 Diabetes (T2D) is the most common form of diabetes, affecting millions of people worldwide. Unlike Type 1 Diabetes, which is an autoimmune disease, Type 2 Diabetes develops when the body becomes resistant to insulin or does not produce enough insulin to regulate blood sugar properly.
In this lecture, we will cover:
- What Type 2 Diabetes is
- The causes and risk factors of Type 2 Diabetes
- Common symptoms and warning signs
- How Type 2 Diabetes is diagnosed
- Management strategies, including lifestyle changes, medication, and long-term care
By the end of this lecture, you will have a comprehensive understanding of Type 2 Diabetes, how it develops, and the best strategies for prevention and management.
2. What is Type 2 Diabetes?
2.1 Definition and Overview
Type 2 Diabetes is a chronic metabolic disorder in which the body cannot use insulin properly, leading to high blood sugar levels (hyperglycemia).
There are two main problems in Type 2 Diabetes:
- Insulin Resistance – The body’s cells do not respond properly to insulin, preventing glucose from entering the cells.
- Insufficient Insulin Production – Over time, the pancreas becomes overworked and unable to produce enough insulin to compensate for insulin resistance.
Unlike Type 1 Diabetes, where insulin production stops entirely, people with Type 2 Diabetes may still produce some insulin, but it is not effective enough to regulate blood sugar properly.
2.2 Key Facts About Type 2 Diabetes
- Accounts for 90-95% of all diabetes cases worldwide.
- Strongly linked to lifestyle factors, such as poor diet, physical inactivity, and obesity.
- Can often be prevented or delayed through healthy lifestyle choices.
- May go undiagnosed for years because symptoms develop gradually.
3. Causes and Risk Factors of Type 2 Diabetes
3.1 What Causes Type 2 Diabetes?
The exact cause of Type 2 Diabetes is complex and involves genetic, lifestyle, and environmental factors.
- Insulin Resistance – The body’s cells become resistant to insulin, forcing the pancreas to produce more insulin to compensate. Over time, the pancreas loses its ability to keep up with the demand.
- Genetics – A family history of diabetes increases the risk of developing Type 2 Diabetes.
- Lifestyle Factors – Poor diet, lack of physical activity, and obesity contribute significantly to insulin resistance.
3.2 Risk Factors for Type 2 Diabetes
Certain factors increase the likelihood of developing Type 2 Diabetes, including:
Modifiable Risk Factors (Can be changed)
- Unhealthy Diet – Diets high in processed foods, sugary drinks, and refined carbohydrates contribute to insulin resistance.
- Physical Inactivity – Lack of exercise reduces the body’s ability to use insulin effectively.
- Excess Weight/Obesity – Fat cells, especially around the abdomen, produce substances that lead to insulin resistance.
- Smoking and Alcohol Consumption – Can increase the risk of Type 2 Diabetes and complications.
Non-Modifiable Risk Factors (Cannot be changed)
- Age – Risk increases after age 45, though it is becoming more common in younger adults and children.
- Family History – Having a parent or sibling with Type 2 Diabetes raises the risk.
- Ethnicity – Certain ethnic groups, including African, Hispanic, South Asian, and Indigenous populations, have a higher genetic risk.
- History of Gestational Diabetes – Women who had diabetes during pregnancy have an increased risk of developing Type 2 Diabetes later in life.
4. Symptoms of Type 2 Diabetes
Type 2 Diabetes often develops gradually, and many people do not realize they have it until complications arise.
4.1 Common Symptoms of Type 2 Diabetes
- Frequent urination (Polyuria) – High blood sugar pulls fluids from tissues, increasing urination.
- Excessive thirst (Polydipsia) – Dehydration due to frequent urination causes persistent thirst.
- Unexplained weight loss – Despite eating normally, the body may start breaking down muscle and fat for energy.
- Increased hunger (Polyphagia) – The body’s cells do not receive enough glucose, causing persistent hunger.
- Fatigue – Lack of insulin function results in low energy levels.
- Blurred vision – High blood sugar levels can affect fluid levels in the eyes.
- Slow wound healing – High blood sugar affects circulation and immune function, leading to slow-healing cuts and infections.
- Tingling or numbness in hands and feet – Nerve damage (diabetic neuropathy) can develop over time.
5. Diagnosis of Type 2 Diabetes
If a doctor suspects Type 2 Diabetes, they will perform the following tests:
5.1 Common Diagnostic Tests
- Fasting Blood Sugar Test – Measures blood glucose after 8 hours of fasting. A result ≥126 mg/dL (7.0 mmol/L) indicates diabetes.
- Hemoglobin A1c Test (HbA1c) – Measures average blood sugar levels over 2-3 months. A result ≥6.5% confirms diabetes.
- Oral Glucose Tolerance Test (OGTT) – After drinking a sugary solution, blood sugar levels are measured. A level ≥200 mg/dL (11.1 mmol/L) after 2 hours indicates diabetes.
- Random Blood Sugar Test – A reading ≥200 mg/dL (11.1 mmol/L) at any time of day suggests diabetes.
6. Management of Type 2 Diabetes
Unlike Type 1 Diabetes, which requires insulin therapy, Type 2 Diabetes can often be managed with lifestyle changes and medication.
6.1 Lifestyle Modifications
- Healthy Diet – Focus on whole foods, vegetables, lean proteins, and whole grains.
- Regular Exercise – At least 150 minutes of moderate-intensity exercise per week improves insulin sensitivity.
- Weight Loss – Losing even 5-10% of body weight can significantly reduce blood sugar levels.
- Stress Management – Reducing stress through meditation, yoga, or hobbies helps regulate blood sugar.
6.2 Medications for Type 2 Diabetes
- Metformin – The first-line medication that reduces liver glucose production.
- Sulfonylureas – Stimulate the pancreas to release more insulin.
- SGLT2 Inhibitors – Help the kidneys excrete excess sugar through urine.
- GLP-1 Receptor Agonists – Slow digestion and improve insulin function.
6.3 Insulin Therapy
If blood sugar remains uncontrolled, insulin injections may be necessary.
7. End of Lecture Quiz
1. What is the primary cause of Type 2 Diabetes?
A) Autoimmune destruction of beta cells
B) Insulin resistance and decreased insulin production
C) Lack of oxygen in the blood
D) Low cholesterol levels
Answer: B) Insulin resistance and decreased insulin production
2. Which lifestyle change is most effective in preventing Type 2 Diabetes?
A) Drinking more coffee
B) Regular exercise and healthy diet
C) Sleeping more than 10 hours a night
D) Avoiding dairy products
Answer: B) Regular exercise and healthy diet
8. Online Resources for Further Learning
- World Health Organization (WHO) – Diabetes Overview
https://www.who.int/health-topics/diabetes - American Diabetes Association (ADA)
https://www.diabetes.org
9. Summary & Key Takeaways
- Type 2 Diabetes is the most common form of diabetes, affecting millions globally.
- Insulin resistance and insufficient insulin production are the main causes.
- A healthy lifestyle can prevent or manage Type 2 Diabetes.
- Early diagnosis is crucial to prevent complications.
