Hidden pain in the left side of the abdomen may be related to eating cold food and other factors, but also trauma, digestive system diseases, urinary system diseases, reproductive system diseases and other causes. 1. Eating cold food to stimulate intestinal contractions and spasms, strenuous exercise leading to intestinal torsion and other physiological factors may cause the left side of the abdomen hidden pain. 2. Trauma: the left side of the abdomen by violent impact, abrasion, sharp instrument stabbing, falling injuries, resulting in abdominal skin, muscle and even abdominal organs damage. 3. Digestive system diseases: ulcerative colitis, colorectal cancer, Crohn’s disease, peritonitis, hemorrhoids, etc. lead to intestinal and peripheral tissue lesions in the left lower abdominal cavity, causing vague pain in the left abdomen. 4. Urinary system diseases: lower ureteral stone, lower ureteral tuberculosis, bladder cancer, prostatitis, etc. lead to obstruction of urinary tract and local injury of urinary tract, which will cause vague pain in the left abdomen. 5. Diseases of reproductive system: If women suffer from pelvic inflammatory disease, endometrial cancer, left fallopian tube cancer, ovarian cancer, etc., which cause inflammatory and cancerous lesions in pelvic tissues, it will also cause vague pain in the left abdomen. Hidden pain in the left side of the abdomen may also be related to factors, and it is recommended to consult a doctor for a clear diagnosis.