Gastric cancer (GC), the third leading cause of cancer-related death globally, is complex and heterogeneous. This review explores multidisciplinary investigations of traditional Chinese medicine (TCM) combined with Western medical practices, emphasizing the development of nutraceuticals for cancer prevention. Using advanced analytical chemistry and food chemistry techniques, this study investigated how TCM components may be optimized for nutraceutical development. Focusing on molecular interactions with GC pathways, particularly the NF-κB, PI3K/Akt, and Wnt/β-catenin pathways, we examined the effects of TCM polyherbal formulas, extracts, and isolated compounds. These agents modulate apoptosis and cellular proliferation, underscoring their potential in preventive strategies. The convergence of nutraceutical and medicine food homology studies highlights a significant shift towards integrating TCM-derived compounds in a preventive health framework. This approach aims not only to enhance efficacy and reduce side effects but also to champion a preventive paradigm using personalized medicine to advance proactive health maintenance and disease prevention. The combination of TCM and western medical practices offers promising avenues for future research and practical applications in GC prevention.