What Are the Differences Between Type 1 and Type 2 Diabetes?

The key differences between type 1 and type 2 diabetes lie in their typical age of onset, underlying causes, and clinical manifestations. Type 1 diabetes predominantly affects younger individuals and is primarily caused by insulin deficiency due to autoimmune destruction of pancreatic beta cells. Patients commonly present with the classic “three more and one less” symptoms: polyuria (excessive urination), polydipsia (excessive thirst), polyphagia (excessive hunger), and weight loss. In contrast, type 2 diabetes typically occurs in older adults and is mainly attributable to insulin resistance—i.e., the body’s inability to use insulin effectively. Patients with type 2 diabetes often have comorbid conditions such as hypertension and hyperlipidemia, and they usually do not exhibit the “three more and one less” symptom complex.