Diabetes Causes, Risk Factors & Early Warning Signs Explained

Causes of Diabetes

The causes vary by diabetes type. Type 1 diabetes is thought to be caused by an autoimmune reaction where the body attacks insulin-producing beta cells by mistake, though no one knows exactly why this happens. Type 2 diabetes begins with insulin resistance, where cells in muscle, fat, and liver don't respond properly to insulin, forcing the pancreas to work harder until it can no longer keep up. Gestational diabetes occurs when placental hormones cause insulin resistance during pregnancy, and pancreatic β-cell dysfunction results in decreased insulin secretion.mayoclinic+3​

Risk Factors

Non-Modifiable Risk Factors

Several risk factors cannot be changed. Age significantly increases diabetes risk, particularly after 45 for type 2 diabetes, though type 1 can develop at any age. Family history plays a crucial role—having a parent or sibling with diabetes substantially increases your risk. Race and ethnicity affect susceptibility, with African Americans, Hispanic/Latino Americans, American Indians, Alaska Natives, Asian Americans, and Pacific Islanders facing higher risk. History of gestational diabetes increases lifetime risk of developing type 2 diabetes later.heart+4​

Modifiable Risk Factors

Many risk factors can be controlled through lifestyle changes. Overweight and obesity represent the main risk factors for type 2 diabetes, especially when fat is stored in the belly area—waist measurements over 40 inches for males or 35 inches for females increase risk. Physical inactivity (less than 3 times weekly) significantly raises diabetes risk. Unhealthy diet high in refined carbohydrates, saturated fats, and sugary beverages impairs glucose metabolism. Smoking is associated with insulin resistance and increased type 2 diabetes risk.niddk.nih+4​

Additional medical conditions increase diabetes risk, including prediabetes, high blood pressure, high cholesterol, non-alcoholic fatty liver disease (NAFLD), polycystic ovary syndrome (PCOS), and cardiovascular diseases.canada+2​

Early Warning Signs

Early warning signs include increased thirst and urination, increased hunger, fatigue, blurred vision, slow-healing sores, numbness or tingling in hands or feet, and unexplained weight loss. In type 1 diabetes, symptoms develop rapidly over several weeks, while type 2 diabetes symptoms develop gradually over several years and may be so mild they go unnoticed. Recognizing these signs early enables timely diagnosis and treatment, reducing the risk of serious complications.forbes+2