Intestinal senescence, often characterized by increased oxidative stress, is linked to gastrointestinal disorders such as inflammatory bowel disease and colorectal cancer. While previous studies have suggested that diets rich in food additives, such as the emulsifier Polysorbate 80 (P80), may influence gut health, the impact of P80 exposure on intestinal senescence remains unclear. This study aimed to explore the effects of P80 on intestinal senescence in a senescence-accelerated mouse prone model. The results revealed that P80 exposure could damage the intestinal barrier, induce oxidative stress, and accelerate intestinal senescence. Mechanistically, P80 activated the peroxisome proliferator-activated receptor-alpha (PPARalpha) and fatty acid-binding protein 1 (FABP1) axis, increasing intestinal fatty acid absorption and triggering lipotoxicity, which promoted senescence. Additionally, P80 exacerbated D-galactose-induced epithelial cell senescence and lipid accumulation via the PPARalpha signalling pathway. Importantly, the PPARalpha antagonist GW6471 mitigated fatty acid uptake and reduced senescence in the intestine. In conclusion, the emulsifier P80 accelerated intestinal senescence by regulating the PPARalpha-FABP1 axis to induce intestinal fatty acid uptake and lipotoxicity, suggesting new insights into the adverse effects of food additives on gut health.