Type 1 diabetes and prolonged fasting

Aims Fasting is common in several religions. The aims of this study were to determine if prolonged fasting (> 25 h) is safe for individuals with Type 1 diabetes and to identify factors associated with success. Methods Patients intending to fast were instructed on insulin dose adjustments, frequent glucose monitoring and when to terminate the fast using a standard protocol. Clinical and epidemiological factors were recorded and a comparison was made between successful and unsuccessful fasters. Results Of 56 subjects who intended to fast, 37 (65%) were successful. Individuals terminated their fast in the presence of either hypoglycaemia or hyperglycaemia and adherence to the protocol was high. There were no serious side-effects of fasting. Successful fasters had greater reductions in insulin dosage and higher HbA(1c). There were no differences between individuals taking intermittent insulin injections and those with continuous infusion pumps. Conclusions Persons with Type 1 diabetes can participate safely in prolonged fasts provided they reduce their usual insulin dose significantly and adhere to guidelines regarding glucose monitoring and indications for terminating fasting.