Pancreatic Lipase as a Therapeutic Target for Obesity Management: Clinical Evidence, Natural Inhibitors, and Future Perspectives

Abstract

Inhibition of pancreatic triacylglycerol lipase remains the only mechanism by which a licensed anti-obesity medicine acts entirely within the intestinal lumen, and it continues to anchor a very large discovery literature devoted to plant-derived inhibitors. That literature has grown far faster than the clinical evidence supporting it, and the resulting imbalance is rarely examined critically. This review evaluates the biochemical rationale for targeting pancreatic lipase, the clinical performance of the mechanism as realised by orlistat and cetilistat, and the quality of the evidence advanced for natural inhibitors, in order to establish what can defensibly be claimed about this target in the management of body weight. Peer-reviewed literature was identified through structured searching of a biomedical bibliographic database and a scholarly metadata index, supplemented by citation tracking and verification of every retained record. The synthesis indicates that the enzymological case for the target is secure, whereas the quantitative link between luminal lipase inhibition and durable weight reduction is comparatively weak and bounded by compensatory energy intake, gastrointestinal tolerability and the substantial secretory reserve of the enzyme. The natural-inhibitor literature is dominated by heterogeneous in vitro assays that are vulnerable to colloidal aggregation, interfacial artefacts and substrate-dependent potency, and inhibitory constants derived from such assays correlate poorly with human outcomes. Human trials of botanical products associated with lipase inhibition claims generally report small, heterogeneous and frequently imprecise effects on body weight, and mechanism attribution is almost never tested directly. Priorities for the field include mechanism-confirmatory human studies using luminal lipolysis endpoints, counter-screening protocols that exclude non-specific inhibition, and reconsideration of lipase inhibition as a component of combination or food-structuring strategies rather than as a standalone therapeutic approach.