A review of existing data suggests that a balanced diet, rather than long-term restriction of carbohydrates or any other single nutrient, maintains a diverse population of intestinal flora and improves metabolic imbalance in patients with RA.
A new review1 sought to determine what effect diet has on symptoms and severity of autoimmune diseases, including rheumatoid arthritis (RA). The review suggests that a balanced diet, rather than long-term restriction of carbohydrates or any other single nutrient, maintains a diverse population of intestinal flora and improves metabolic imbalance in patients with RA.
According to the review’s authors, low-carbohydrate diets may be considered for RA patients due to their increased risk of cardiovascular diseases. At the same time, however, altering a patient’s diet to restrict a particular nutrient, including carbohydrates, can alter intestinal microflora. The authors note that changes in the gut microbiota can be concerning for patients with RA because the gut microbiota is reported to regulate the T-cell phenotype and T-cell-mediated immunity.
Per the studies consulted, the gut microbiome of RA patients have “distinct gut microbiota compared to control diseases or healthy subjects,” the authors write. And while this unique microbiome may be only a secondary effect of the disease, existing studies from early-stage or RA patients “seem to reflect more disease-related microbiome.” The authors state that an imbalance of Prevotella species in intestinal microbiome, for example, has been identified in studies with early-stage RA patients, though they add that further investigation is needed to clarify how the biased microbiome would contribute to the pathophysiology of RA.
Further, because RA is an autoimmune disease, they write, “it can be speculated that there would be molecular similarity between bacterial component(s) and potential autoantigen(s) (i.e., “molecular mimicry”), and that T-cell recognition of the bacterial component might trigger the pathogenic autoimmunity.”
Another of the studies2 consulted, a paper slated for publication this August, examined the connection between long-term dietary quality, measured per to the 2010 Alternative Healthy Eating Index (AHEI-2010), and the incidence of RA. In that study, women with higher AHEI-2010 scores had a lower risk of developing RA. Based on that result, the authors concluded “an overall healthy diet quality may be more beneficial for RA risk reduction than individual foods and nutrients, particularly for early-onset seropositive RA.” The authors of the current review note that elsewhere, too, dietary fiber has been shown to attenuate inflammation, while fiber deficiency has been linked to increased inflammation.
Ultimately, the researchers write, diet is “one of the modifiable environmental factors for the onset and/or disease outcome of RA.” Patients suffering from RA symptoms may be able to reduce those symptoms by first addressing metabolic imbalance and by consuming a diet that modulates the gut microbiota. The authors concluded that “diet may gradually adjust the physiological condition as well as immunological response in RA patients.”
Further, they state that a balanced diet is of key importance for managing RA symptoms. A balanced diet that includes dietary fiber helps to maintain diverse intestinal flora, as well as to reduce metabolic imbalances and inflammation. Finally, they caution that “long-term restriction of a single nutrient may not be advisable and should only be done under careful observation by nutritional experts.”
1. Masuko K, “A potential benefit of ‘balanced diet’ for rheumatoid arthritis,” Frontiers in Medicine. Published online May 15, 2018.
2. Hu Y et al., “Long-term dietary quality and risk of developing rheumatoid arthritis in women.”