Oral lipid tolerance test (OLTT) is used to measure postprandial triglyceride levels and whole-body lipid homeostasis after consumption of a standardized meal.

Mixed Meal Tolerance Test (MMTT) provides a more comprehensive physiological stimulus to insulin secretion since 13-cells are responsive to certain amino acids and fatty acids in addition to glucose.

Oral glucose tolerance test (OGTT) is used to interrogate the effects of a therapeutic intervention in a clinical research setting and by clinicians to diagnose forms of glucose intolerance and type 2 diabetes.