Longevity & AgingFive Days of Fasting Shrinks Fat, Lifts Mood, and Reshapes Metabolism
A 5-day water-only fast in 42 middle-aged women produced significant reductions in body mass, waist circumference, leptin, glucose, and insulin, alongside rising ketone bodies signaling a metabolic shift to fat burning. Mood improved markedly—vigor increased and tension fell—despite modest rises in inflammatory markers (TNF-alpha, IL-6). Irisin declined, while BDNF and adiponectin held steady. Notably, psychological factors predicted outcomes: women with higher pre-fast well-being, emotional intelligence, and lower impulsivity lost more fat mass, while those scoring higher in neuroticism and impulsivity lost more lean mass. These findings suggest that personalized, psychologically informed fasting strategies may optimize benefits and minimize lean-tissue losses.
