The GLOW Study - The YANG System

Inclusion Criteria: T1DM patients * Subjects willing to sign an informed consent form (ICF), * Adult subjects, age ≥ 18, ≤ 50 years old * Body Mass Index (BMI) 20≥, ≤ 27.5 \[kg/m2\] * Subjects willing to comply to study protocol requirements (exercises, ketone ester drinks, alcohol, study visits, blood sampling etc) * Patients with type 1 diabetes mellitus (T1DM) according to WHO criteria, diagnosed for at least 12 months prior to screening * Subjects being on insulin pump for at least 12 months Healthy Volunteers * Subjects willing to sign an informed consent form (ICF), * Adult subjects, age ≥ 18, ≤ 50 years old * BMI 20≥, ≤ 27.5 * Subjects willing to comply to study protocol requirements (exercises, ketone ester drinks, alcohol, study visits, blood sampling etc) * Healthy subjects, as self-declared and confirmed by screening assessments and Principal Investigator's judgment Exclusion Criteria: * Subjects with a contraindication to undergo challenging tests (i.e., ischemic heart disease, epilepsy, panhypopituitarism, hypoadrenalism, hypothyroidism, known allergic reaction to ibuprofen/paracetamol/acetylsalicylic acid) * For people with diabetes: History of severe hypoglycaemia in the previous 6 months. Severe hypoglycaemia is defined as hypoglycaemia resulting in loss of consciousness or seizure * For people with diabetes: History of diabetic ketoacidosis requiring emergency room visit or hospitalization in the previous 6 months * Any blood disorder identified by haematocrit \<30% or \>55% * History of hepatitis B, hepatitis C, or HIV * A condition requiring or likely to require magnetic resonance imaging (MRI) during the study duration * Female subjects who are pregnant, planning on becoming pregnant or nursing * Any disorder, which in the investigator's opinion might jeopardise subject's safety or compliance with the protocol. * Coagulation disorder, wound healing and bleeding disorder or taking anticoagulant medication * Any long-term drug treatments other than insulin, such as statins, low-dose aspirin, fibrates etc. * The presence of any other active implanted device except for insulin pumps (as defined further in protocol) * The presence of any other CGM sensor or transmitter located in abdomen (other location is acceptable) * Impaired fasting glucose or impaired glucose tolerance (for healthy volunteers) * Any contraindication to the use of the Yang system as listed in the device IFU (i.e. any known allergy to PDMS)