Competitive catabolism drives hyperglycemia and hyperinsulinemia in obesity.

Competitive catabolism of fatty acids and glucose in obesity causes hyperglycemia and hyperinsulinemia, driven by a physiological circuit identified through modeling.

• Why it matters: Understanding how multiple nutrients are simultaneously regulated is crucial for addressing metabolic disorders like type 2 diabetes, yet the mechanisms remain unclear.
• What they did: A differential equation model based on mass action kinetics was developed to simulate fasting metabolic homeostasis, revealing how fixed energy demands lead to nutrient competition and insulin's indirect role in glucose regulation.
• The result: The model predicts that increased fat mass in obesity promotes lipolysis, releasing fatty acids that compete with glucose for oxidation, elevating blood glucose and insulin levels, thus elucidating a circuit that drives diabetic conditions.