New research paper on fasting, autophagy and advanced fat loss
Read it here: https://pmc.ncbi.nlm.nih.gov/articles/PMC11790841/ My review is as follows -> Core finding: - The paper shows a second fat-mobilizing system in adipocytes. - Early fasting and adrenergic stress rely on the canonical neutral lipases, with ATGL as the rate-limiting enzyme. - Prolonged fasting shifts control to a lysosomal pathway that uses lysosomal acid lipase (LAL/LIPA) and is driven by MiT/TFE transcription factors (TFEB, TFE3, MITF). - Blocking lysosomes pharmacologically or genetically reduces fasting-induced release of free fatty acids and glycerol in mice. - Human support: nutrient restriction in human adipocytes and human fat explants also shows LIPA-dependent lipolysis. Simple physiology model (sequence during a fast): 1. 0–6 h: post-absorptive. Glycogen supplies glucose. Lipolysis is low. 2. 6–12 h: rising catecholamines. ATGL-dependent lipolysis increases. Free fatty acids rise. 3. ~12–24+ h: shift in adipocytes. Lysosomal program ramps up (TFEB/TFE3/MITF↑, LAL↑). LIPA-dependent lipolysis dominates. Ketones rise. Glucose falls. 4. Refeed: lysosomal signals ease; other lipases and lipogenesis genes change again. Bottom line: - Fasting uses two lipolytic systems with different time courses. - ATGL handles rapid responses. - Lysosomal LIPA handles prolonged fat mobilization. - For advanced fat loss, design fasting that regularly enters the ≥12–24 h window, manage refeeds, and support with electrolytes and sensible activity. - This approach aligns physiology with practice and may improve consistency in fat loss beyond short fasts.