Potassium-Rich, Gluten-Free Diets for Patients with Sjögren's Syndrome: A Mini-Review

Sjögren's syndrome (SS) is an autoimmune disease and its management is palliative. There is no specific dietary protocol for SS patients. A gluten-free diet has been tested in SS patients with celiac disease (CD) and indicated modest improvements. Whether gluten-free diets per sè could alleviate autoimmune inflammatory processes in the salivary glands of SS patients with associated CD or even in SS patients without CD is an interesting hypothesis and warrants clinical studies. Hypokalemia in SS patients is among the most frequent sequelae of renal tubular acidosis. Supplementation with potassium (K)-rich diets can reduce inflammation and oxidative stress. K level in CD patients is highly abnormal at diagnosis and gluten-free diets help to normalize its serum level in CD patients. Furthermore, treatment of severe cases of SS requires concomitant glucocorticoid therapy and K supplementation. Results of two separate clinical trials in (i) patients with rheumatoid arthritis (RA) –a disease with similar pathology to SS- indicated that the enhanced serum cortisol followed K supplementation, and in (ii) celiac patients, serum K levels were normalized after the administration of a gluten-free diet. We reviewed the literature extensively on this topic to propose a hypothesis to address this problem and suggest a novel potential for K-rich, gluten-free diets in SS patients. Based on causal associations, we propose that higher K absorption and cortisol secretion following gluten-free diets accompanied by K-rich diets in SS patients with low serum potassium levels, may confer a higher therapeutic potential. Clinical trials are needed to test this hypothesis.