What is the difference between type 1 and type 2 diabetes?

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1. 1

   Diabetes (Wikipedia)

   WikipediaPublished Oct 10, 2026Checked Oct 11, 2026

   “Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes tends to progress in severity, and is due to either a reduced production of the hormone insulin by the pancreas or unresponsiveness of bodily cells to insulin's effects. Classic symptoms include the three Ps: polydipsia (excessive thirst), polyuria (excessive urination), and polyphagia (excessive hunger), together with weight loss and blurred vision. If left untreated, the disease can lead to many health complications, including disorders of the cardiovascular system, eye, kidney, and nerves. The major types of diabetes are type 1 and type 2. The most common type is type 2. The most common treatment for type 1 is insulin replacement therapy (insulin injections), while anti-diabetic medications (such as metformin and semaglutide or tirzepatide) and lifestyle modifications can be used to manage type 2. Gestational diabetes, a form that sometimes arises during pregnancy, normally resolves shortly after delivery.”

2. 2

   Type 2 diabetes (Wikipedia)

   WikipediaPublished Oct 7, 2026Checked Oct 11, 2026

   “Type 2 diabetes (T2D), formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urination, fatigue and unexplained weight loss. Other symptoms include increased hunger, having a sensation of pins and needles, and sores (wounds) that heal slowly. Symptoms often develop slowly. Long-term complications from high blood sugar include heart disease; stroke; diabetic retinopathy, which can result in blindness; kidney failure; and poor blood flow in the lower limbs, which may lead to amputations. A sudden onset of hyperosmolar hyperglycemic state may occur; however, ketoacidosis is uncommon. Type 2 diabetes primarily occurs as a result of obesity and lack of exercise. Some people are genetically more at risk than others. Type 2 diabetes makes up about 90% of cases of diabetes, with the other 10% due primarily to type 1 diabetes and gestational diabetes. Diagnosis of diabetes is by blood tests such as fasting plasma glucose, oral glucose tolerance test, or glycated hemoglobin (A1c).”

3. 3

   Glycaemic Variability and C-Peptide in Bangladeshi Children, Adolescents, and Young Adults With Diabetes: A Prospective Study.

   Endocrinology, diabetes & metabolism (Flabe et al.)Published Nov 1, 2026Checked Oct 11, 2026

   “Fasting C-peptide was available for 46 participants. The coefficient of variation (CV) of glucose as the primary metric of variability; time in range, time above range, and time below range as secondary metrics; and independent predictors of CV on multivariable regression. Mean CV was 39.4% (SD 9.2), and 59 of 97 participants (60.8%) were at or above the recommended target of 36%. CV was higher in Type 1 than Type 2 diabetes (41.9% vs. 33.3%). Lower fasting C-peptide was independently associated with higher CV after adjustment for diabetes type, age, and insulin dose (-1.94 percentage points per ng/mL, 95% CI -3.35 to -0.53; model R-squared 0.52), with a graded relationship across pre-specified C-peptide categories for CV, time in range, and time below range. Glycaemic variability substantially exceeds international targets in this setting. Fasting C-peptide, available for fewer than half of the cohort, showed a graded association with variability that is best regarded as hypothesis-generating; if confirmed in larger studies, it could offer a low-cost means of identifying children at highest variability risk where CGM access is limited.”

4. 4

   C-Peptide Provides Critical Contextual Insight Into Elevated Glucose Values During Progression to Type 1 Diabetes.

   Diabetes care (Sims et al.)Published Oct 1, 2026Checked Oct 11, 2026

   “The regulatory approval and growing pipeline of disease-modifying therapies for presymptomatic type 1 diabetes have sparked an increase in screening for the presence of islet autoantibodies in individuals who may not have yet developed clinical symptoms of disease. The staging system that is currently employed to define type 1 diabetes diagnosis in presymptomatic and symptomatic phases is based on the presence of islet autoantibodies and glycemic status. Here, we make the case to consider using C-peptide values to provide context for glycemia. Inclusion of C-peptide could result in better prediction of progression to clinical disease and more specificity for features typically associated with type 1 diabetes (and, thus, be less susceptible to confounding influences on glycemia like age and insulin resistance). It also could more rapidly identify responses to disease-modifying therapies. The implementation and translation of these findings will be key to long-term success in type 1 diabetes prediction and disease modification strategies.”