Common symptoms of diabetes include excessive thirst, frequent urination, unexplained weight loss, extreme hunger, fatigue, blurred vision, and slow-healing wounds. However, some people with Type 2 diabetes may not experience noticeable symptoms, making regular screening important.

The exact cause of diabetes varies depending on the type. Type 1 diabetes is believed to be an autoimmune condition where the immune system attacks insulin-producing cells in the pancreas. Type 2 diabetes is often linked to genetics, obesity, and lifestyle factors like poor diet and lack of exercise. Gestational diabetes occurs during pregnancy and is related to hormonal changes and insulin resistance.

Diabetes is diagnosed through blood tests that measure blood sugar levels. The most common tests include the fasting blood glucose test, the oral glucose tolerance test (OGTT), and the HbA1c test, which measures average blood sugar levels over the past two to three months. A diagnosis is typically made if blood sugar levels are above certain thresholds.