Condition

Type 1 Diabetes: Autoimmune Diabetes and Insulin Management

Type 1 diabetes destroys insulin-producing cells, requiring lifelong insulin replacement. Modern technology — CGM and insulin pumps — has transformed quality of life for people with T1DM.

Cause
Autoimmune destruction of beta cells
Peak onset
Childhood to 30s (can occur at any age
UK prevalence
~400,000 people
Insulin required
Lifelong — without it, DKA develops
DKA is a Medical EmergencyDiabetic ketoacidosis (DKA) occurs when insulin is severely deficient. Features: vomiting, abdominal pain, fruity breath, drowsiness, rapid deep breathing (Kussmaul). Call 999/911 and do not stop insulin during illness.

Type 1 vs Type 2: Key Differences

FeatureType 1Type 2
CauseAutoimmune (GAD, IA-2, ZnT8 antibodies)Insulin resistance + relative insulin deficiency
OnsetOften rapid, acute (DKA)Gradual, often asymptomatic
AgeAny age; typically youngerUsually >40 (but rising in youth)
Body weightUsually normal or thin at onsetUsually overweight
InsulinAlways requiredOral drugs first; insulin later in many
C-peptideVery low/undetectable (no beta cell)Normal or high initially

Insulin Regimens

CGM Changes EverythingContinuous glucose monitors (Dexterity/Libre/Dexcom) replace or supplement fingerprick testing. Real-time glucose trends allow earlier correction and reduce hypoglycaemia. The NHS now funds CGM for all people with T1DM.
What is the honeymoon period?
Shortly after T1DM diagnosis, residual beta cells may still produce some insulin, causing reduced insulin requirements — the 'honeymoon phase.' It lasts weeks to months; insulin is still required throughout.
How do I manage T1DM during illness (sick day rules)?
NEVER stop insulin during illness — glucose and ketones usually rise. Check glucose every 2 hours. Check blood or urine ketones. Extra rapid-acting insulin may be needed. Stay hydrated. If vomiting or ketones are high, go to hospital.
What is carbohydrate counting?
Matching rapid-acting insulin dose to the amount of carbohydrate eaten (usually 1 unit per 10g carb — but individual ratios vary). Taught by a diabetes team as part of the DAFNE (Dose Adjustment For Normal Eating) programme.
Can Type 1 diabetes be cured?
Not currently. Pancreas and islet cell transplantation can achieve remission but require lifelong immunosuppression. Encapsulated islet transplantation and gene therapy are in clinical trials.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.