Relationship between diet and postoperative pain: A scoping review

Poorly controlled postoperative pain is a risk factor for persistent post-surgical pain. Inflammation, as influenced by diet, has been incriminated as a significant factor in pain sensitivity and persistent pain. While the role of diet in chronic pain conditions has been explored, its influence on acute postoperative pain remains understudied. This scoping review aims to collate available evidence on the impact of diet on acute post-surgical pain and identify areas for future research. We performed a comprehensive search from the year 2000 onwards in PubMed, Scopus, and Cochrane databases. Our mesh terms included "diet", "inflammation", "post-surgical pain", and "post-operative pain". Both animal and human studies were included. There is a dearth of literature regarding the impact of diet on acute postoperative pain in humans. The few studies performed in surgical populations point to a beneficial effect of polyamine-deficient and immunonutrition diets on postoperative pain. Mechanisms include N-methyl-D-aspartate (NMDA) receptor modulation, increased responsiveness to morphine, and reduction of inflammation. Although animal data suggests intermittent fasting to be helpful and high-fat diets to be linked with worsened pain sensitivity, there are no studies in humans investigating the association of intermittent fasting and high-fat diets with postoperative pain. More human studies are expected to understand the effect of diet on postoperative pain in diverse surgical populations.