Along with pharmacologic therapies, a range of lifestyle approaches may also improve symptoms, physical function, and quality of life in patients with rheumatoid arthritis (RA).1 Among such interventions, the role of diet and the effects of specific nutrients in RA pathogenesis and management are topics of increasing interest. Studies have demonstrated various benefits associated with certain dietary patterns and nutrients in RA patients, including possible protective effects on disease risk and progression.2
In a systematic review published recently in Nutrition Reviews, Philippou et al examined 70 studies and concluded that high doses of omega-3 polyunsaturated fatty acids led to reduced disease activity and lower rates of medication failure in RA patients.3 Additionally, vitamin D supplementation, sodium restriction, and the Mediterranean diet were linked to improvement in certain RA outcomes, while findings regarding “vegetarian, elimination, peptide, or elemental diets suggested that responses are very individualized,” they wrote.3-5 “Some dietary approaches may improve RA symptoms and thus it is recommended that nutrition should be routinely addressed.”3
In a randomized controlled crossover trial of 50 RA patients published in Nutrition Journal, an anti-inflammatory dietary intervention was associated with significant improvements in blood lipid profiles, highlighting its potential cardioprotective effects in this population.6 Other studies have noted a mediating role of the gut microbiota on the connection between diet and inflammation and other RA outcomes.7
Among the numerous possible directions for future research in this area, experts point to the field of “omics technologies” as an important focus that could ultimately yield key insights regarding the precise effects of certain nutrients and dietary patterns on disease prevention and management in RA.8 Examples of “omics” include genomics and microbiomics.
We further explored the topic of nutrition and RA in an interview with Leanna Wise, MD, rheumatologist and assistant professor of clinical medicine in the division of rheumatology at the Keck School of Medicine at the University of Southern California in Los Angeles.
What does the available evidence currently suggest about the role of diet and the impact of specific nutrients on RA symptoms?
It is important to first know that for nearly all diseases, it is very difficult to study the exact role of nutrition in treatment of the disease. There are so many variables that can complicate the picture, including the methodology of nutrition studies, changing dietary patterns throughout the different stages of one’s life, the accuracy of patient-reported food intake, concurrent lifestyle changes, and other factors.
With that in mind, the data we have on diet and RA so far is based on just a few short-term small trials as well as retrospective analyses of large data sets. Despite these limitations, the literature does indeed suggest that a Mediterranean diet may be particularly helpful for its anti-inflammatory effects in RA.9
More specifically, there is evidence that consumption of anti-inflammatory compounds such as omega-3 fatty acids and polyphenols – present in high concentrations in spices, herbs, green tea, and many fruits and vegetables – may be helpful in fighting inflammation and quelling RA symptoms.10,11 Data also suggests that high salt, soda, and meat intake may pose a higher risk of RA development. However, none of these nutrients have been directly studied for their role in RA treatment.
What are the possible underlying mechanisms, including potential effects on inflammation and the gut microbiome?
The anti-inflammatory effects of dietary compounds likely tip the systemic immune response from autoimmunity to a more regulated state through modulation of a variety of cytokines and immune cells. The exact physiology behind this has yet to be determined, but given the low bioavailability of many anti-inflammatory foods, direct modulation of the gut microbiome with subsequent improved immune regulation is one of the proposed mechanisms.
The composition of the gut microbiome and its intersection with the immune system is one of the promising new frontiers of rheumatology and medicine in general. Evidence suggests that improved immune regulation may occur through directly stimulating increased numbers of “good” bacteria, decreasing translocation of bacteria from the gut to the bloodstream, or affecting products of bacterial metabolism.12,13
It is also important to realize that this is still a burgeoning field, and questions remain as to whether gut dysbiosis is a cause or consequence of RA.
What are recommendations for clinicians about how to advise RA patients on nutrition for optimal disease management?
Many patients are very interested in treating their RA with lifestyle changes in addition to medications. As aforementioned, the Mediterranean diet has the best supporting evidence and allows for a variety of enjoyable anti-inflammatory foods – and many patients are happy to hear that the diet includes red wine.
Additionally, patients often ask if they should switch to an extreme diet such as a keto or paleo diet. There really isn’t any data to support the use of these or other strict diets in RA, and rheumatologists should hesitate to endorse these diets, as they are unsustainable for many patients.
It is also important to note that given the frequent comorbidities seen in RA, dietary counseling should be given with the goal of not just controlling the RA but also of treating or preventing co-existing chronic conditions such as cardiovascular disease.14 Along the same lines, since obesity has been associated with worse RA outcomes, increased rates of disability, and reduced medication efficacy, addressing factors that lead to obesity in the RA patient population is vital.15,16
What are some of the remaining research needs in this area?
From a pathophysiology perspective, it is clear that further research is needed to understand the undoubtedly complicated relationship between the gut microbiome and the immune system. Other potential areas of research include whether or not the benefits of anti-inflammatory foods are maximized through eating the whole food itself rather than a supplement of the purified nutrient in question; how frequently an individual needs to consume anti-inflammatory foods in order to receive a benefit; and whether there is any role for certain dietary compounds to act as preventive measures in preclinical disease.
Are there any additional points that clinicians should consider regarding this topic?
Physicians and other healthcare providers would benefit from having more extensive education on the role of clinical nutrition and chronic disease. Personally, I think just as much time should be devoted to clinical nutrition and dietary education in medical school as is devoted to surgery or internal medicine. Despite many patients seeking advice in regard to dietary changes for chronic disease management, most clinicians are very underprepared on this subject.17 In this era of widespread chronic disease, clinicians – and the rest of the healthcare system – are obligated to not just manage medications to control disease, but also to treat disease through a lifestyle approach.
- Managing daily life with rheumatoid arthritis: strategies, skills and tools. Hospital for Special Surgery. May 4, 2018. Accessed online March 29, 2021.
- Gioia C, Lucchino B, Tarsitano MG, Iannuccelli C, Di Franco M. Dietary habits and nutrition in rheumatoid arthritis: Can diet influence disease development and clinical manifestations? Nutrients. 2020;12(5):1456. doi:10.3390/nu12051456
- Philippou E, Petersson SD, Rodomar C, Nikiphorou E. Rheumatoid arthritis and dietary interventions: systematic review of clinical trials. Nutr Rev. 2021;79(4):410-428. doi:10.1093/nutrit/nuaa033
- Alwarith J, Kahleova H, Rembert E, et al. Nutrition interventions in rheumatoid arthritis: the potential use of plant-based diets. A review. Front Nutr. 2019;6:141. doi:10.3389/fnut.2019.00141
- Athanassiou P, Athanassiou L, Kostoglou-Athanassiou I. Nutritional pearls: diet and rheumatoid arthritis. Mediterr J Rheumatol. 2020;31(3):319-324. doi:10.31138/mjr.31.3.319
- Hulander E, Bärebring L, Turesson Wadell A, et al. Diet intervention improves cardiovascular profile in patients with rheumatoid arthritis: results from the randomized controlled cross-over trial ADIRA. Nutr J. 2021;20(1):9. doi:10.1186/s12937-021-00663-y
- Coras R, Murillo-Saich JD, Guma M. Circulating pro- and anti-inflammatory metabolites and its potential role in rheumatoid arthritis pathogenesis. Cells. 2020;9(4):827. doi:10.3390/cells9040827
- Cassotta M, Forbes-Hernandez TY, Cianciosi D, et al. Nutrition and rheumatoid arthritis in the ‘omics’ era. Nutrients. 2021;13(3):763. doi:10.3390/nu13030763
- Petersson S, Philippou E, Rodomar C, Nikiphorou E. The Mediterranean diet, fish oil supplements and rheumatoid arthritis outcomes: evidence from clinical trials. Autoimmun Rev. 2018;17(11):1105-1114. doi:10.1016/j.autrev.2018.06.007
- Stamp LK, James MJ, Cleland LG. Diet and rheumatoid arthritis: a review of the literature. Semin Arthritis Rheum. 2005;35(2):77-94. doi:10.1016/j.semarthrit.2005.05.001
- Khan H, Sureda A, Belwal T, et al. Polyphenols in the treatment of autoimmune diseases. Autoimmun Rev. 2019;18(7):647-657. doi:10.1016/j.autrev.2019.05.001
- Jubair WK, Hendrickson JD, Severs EL, et al. Modulation of inflammatory arthritis in mice by gut microbiota through mucosal inflammation and autoantibody generation. Arthritis Rheumatol. 2018;70(8):1220-1233. doi:10.1002/art.40490
- Guerreiro CS, Calado Â, Sousa J, Fonseca JE. Diet, microbiota, and gut permeability-the unknown triad in rheumatoid arthritis. Front Med (Lausanne). 2018;5:349. doi:10.3389/fmed.2018.00349
- Crowson CS, Liao KP, Davis JM 3rd, et al. Rheumatoid arthritis and cardiovascular disease. Am Heart J. 2013;166(4):622-628.e1. doi:10.1016/j.ahj.2013.07.010
- Levitsky A, Brismar K, Hafström I, et al. Obesity is a strong predictor of worse clinical outcomes and treatment responses in early rheumatoid arthritis: results from the SWEFOT trial. RMD Open. 2017;3(2):e000458. doi:10.1136/rmdopen-2017-000458
- Liu Y, Hazlewood GS, Kaplan GG, Eksteen B, Barnabe C. Impact of obesity on remission and disease activity in rheumatoid arthritis: a systematic review and meta-analysis. Arthritis Care Res (Hoboken). 2017;69(2):157-165. doi:10.1002/acr.22932
- Vetter ML, Herring SJ, Sood M, Shah NR, Kalet AL. What do resident physicians know about nutrition? An evaluation of attitudes, self-perceived proficiency and knowledge. J Am Coll Nutr. 2008;27(2):287-298. doi:10.1080/07315724.2008.10719702