Type 2 diabetes is primarily caused by a combination of insulin resistance and inadequate insulin production by the pancreas. In insulin resistance, the body's cells in muscle, fat, and liver do not respond properly to insulin, so they fail to take in enough glucose from the blood. Meanwhile, the pancreas cannot produce enough insulin to compensate, leading to elevated blood sugar levels
. Several factors contribute to the development of type 2 diabetes:
- Genetics: Having a family history of type 2 diabetes significantly increases risk. Specific gene variants affect insulin resistance and insulin production, and these genetic factors interact with lifestyle influences
- Obesity and Overweight: Excess body fat, especially around the abdomen, is the biggest risk factor because it promotes insulin resistance. About 80% of people newly diagnosed with type 2 diabetes are overweight or obese
- Unhealthy Lifestyle: Poor diet (high in refined carbs, sugary drinks, processed meats), lack of physical activity, smoking, and excessive alcohol consumption increase risk
- Age: Risk increases with age, partly due to weight gain and reduced physical activity over time
- Other Health Conditions: High blood pressure, high cholesterol, fatty liver disease, polycystic ovary syndrome (PCOS), and history of gestational diabetes also raise risk
- Ethnicity: Certain ethnic groups (e.g., South Asian, Chinese, African-Caribbean) are at higher risk and may develop the disease earlier
In summary, type 2 diabetes develops when genetic predisposition combines with environmental and lifestyle factors that cause insulin resistance and impair insulin production, resulting in chronically high blood sugar levels
