Diet modification reduces pain and improves function in adults with osteoarthritis: a systematic review

Abstract Background The effect of dietary modifications on pain and joint function in adults with osteoarthritis (OA) is an emerging area of study. This systematic review aimed to evaluate if adults with OA who consume diets with a higher proportion of plant phenols and omega‐3 fatty acids would have less pain and improved joint function than those with a higher proportion of saturated fatty acids, omega‐6 fatty acids and refined carbohydrates. Methods Database searches of CINAHL (EBSCO), Clinical Trials (NIH‐NLM), Cochrane Library (Wiley), Dissertation & Thesis Global (ProQuest), Embase (Elsevier), Medline (OVID), PubMed (NLM), Scopus (Elsevier), Web of Sciences (Clarivate) for clinical trials identified 7763 articles published between January 2015 and May 2023. After an independent review of the articles, seven randomised clinical trials and one nonrandomised clinical trial were included in the analysis. Because of the heterogeneity of the outcome measures, a meta‐analysis was not possible. Results Participants who were instructed to consume high‐phenol/high‐omega‐3 fatty acid diets reported significant improvements in pain and physical function scores. The greatest improvement was reported by those who consumed a diet that had the most omega‐3 fatty acids. Conclusion Because of the high risk of bias, the strength of the evidence is limited. However, there is evidence that counselling adults with OA to replace refined grains and processed foods with whole plant foods, fish and plant oils may have a favourable effect on pain and physical function. Routine follow‐up care regarding these diet modifications may be necessary to ensure adherence to this therapy.