The project will evaluate 1) the postprandial metabolism and 2) continuous glucose levels in subjects diagnosed with Idiopathic Ketotic Hypoglycemia (IKH)) and healthy control subjects.

IKH is a common, but not fully understood, condition in children, and in some the condition may persist in adulthood. In the present study we seek to evaluate the postprandial metabolism in adult subjects diagnosed with IKH through a clinical study including:

1. two test days, where the subjects completes a) an oral glucose tolerance test (OGTT) and b) a miced meal test (MMT). Before, during and after ingestion of the OGTT/MMT, blood samples will be frequently drawn for the evaluation of plasma glucose, hormones, amino acids and more. During both tests, the subjects will recieve a continuous infusion of primed glucose tracer to further evaluate the glucose metabolism.
2. a 14-day period where the subjects will lead the usual lives, wearing a continuous glucose monitor (CGM). This will enable us to evaluate long-term differences in plasma glucose levels in IKH.

Inclusion Criteria:

• IKH-participants:
• Verified diagnosis of IKH by health professional
• BMI of 18-30 kg/m2
• Normal liver- and kidney function
• informed consent

Healthy control participants

• Normal glucose tolerance
• BMI of 18-30 kg/m2
• Normal liver- and kidney function
• informed consent

Exclusion Criteria:

• A history of diabetes
• close family members with diabetes
• use of drugs affecting the glucose metabolism that cannot be paused
• anemia
• any condition that the study investigators deem unacceptable for participation
• pregnancy or breastfeeding.