Pancreatic cancer, characterised by high mortality and late diagnosis, urgently requires improved early detection methods. Unintentional weight loss, reported by 70-75% of patients prior to diagnosis, may serve as a key early marker. This systematic review and meta-analysis evaluated the extent of pre-diagnostic weight loss in pancreatic cancer patients compared with matched controls. Thirteen studies encompassing 12,081 cases and 367,678 controls were analysed, revealing a medium standardised mean difference (SMD = 0.51, [95% CI 0.31-0.71]) equivalent to a 2.26 kg/m2 BMI reduction in people with pancreatic cancer. Significant heterogeneity was observed, influenced by country, publication year, cancer type and diabetes status. Weight loss may serve as a useful non-invasive biomarker for early pancreatic cancer detection, especially in those with new-onset diabetes. Using quantified weight loss data could enhance the accuracy of predictive algorithms, allowing their inclusion in EMR based detection pipelines, ultimately aiding earlier detection and improving survival outcomes.