Metabolic and Neuroendocrine Responses to Intermittent Fasting in Obesity

Area of Science:

• Chrononutrition and metabolic health
• Neuroendocrinology of obesity
• Dietary interventions for weight management

Background:

• Intermittent fasting (IF) modulates circadian rhythms, metabolism, and neuroendocrine function in obesity.
• Orexin-A, a hypothalamic neuropeptide, may link fasting to metabolic homeostasis.
• Evaluating IF protocols (16:8, 5:2) against a Mediterranean diet is crucial for obesity management.

Purpose of the Study:

• To assess long-term metabolic and neuroendocrine effects of 16:8 and 5:2 IF protocols.
• To compare IF interventions with a hypocaloric Mediterranean diet in adults with obesity.
• To investigate the role of Orexin-A in IF-induced metabolic adaptations.

Main Methods:

• Thirty adults with obesity underwent 12 months of either 16:8 IF, 5:2 IF, or a Mediterranean diet.
• Anthropometric, metabolic, inflammatory markers, and Orexin-A levels were measured periodically.
• Dietary patterns influenced participant allocation to interventions.

Main Results:

• Both IF protocols showed faster improvements in BMI, adiposity, lipids, glucose, and inflammation than the Mediterranean diet.
• The 16:8 IF regimen demonstrated consistent adaptation with sustained Orexin-A increases, linked to metabolic flexibility and reduced inflammation.
• The 5:2 IF protocol yielded variable metabolic and neuroendocrine responses.

Conclusions:

• The 16:8 time-restricted feeding protocol is an effective, sustainable chrononutritional strategy for obesity.
• 16:8 IF reinforces circadian organization, improves inflammatory balance, and activates orexinergic pathways.
• This IF model offers a promising intervention for obesity-related metabolic and neuroendocrine dysfunctions.