Which statement best differentiates type 1 diabetes from type 2 diabetes?

• A. Type 1 is autoimmune destruction of insulin-producing beta cells, whereas type 2 is characterized by insulin resistance with relative insulin deficiency
• B. Type 1 typically presents in obesity; Type 2 does not
• C. Type 1 is caused by steroid use; Type 2 is autoimmune
• D. Type 1 never requires insulin; Type 2 always requires insulin

Answer: (A)

Distinguishing type 1 from type 2 diabetes comes down to the mechanism of insulin deficiency. Type 1 is caused by autoimmune destruction of the pancreatic beta cells, leading to an absolute lack of insulin. This often appears in younger individuals, can present with ketoacidosis, and almost always requires insulin therapy from diagnosis. Type 2 is driven by insulin resistance with a progressive, relative insulin deficiency as the beta cells wear out; it’s commonly linked to obesity and metabolic syndrome and may be managed initially with lifestyle changes and oral medications, with insulin needed later in some cases.

The statement that best differentiates them is that type 1 involves autoimmune destruction causing absolute insulin deficiency, while type 2 involves insulin resistance with a relative deficiency. The other options don’t fit the typical patterns: type 1 isn’t defined by obesity at onset, isn’t caused by steroid use, isn’t autoimmune, and type 1 can require insulin.