Objective
Patients with RA often ask if specific foods, popularized as “inflammatory” or “anti-inflammatory,” can improve or worsen their RA. We surveyed patients regarding diet and RA symptoms.
Methods
We mailed a diet survey to 300 subjects in a single-center RA registry at a large academic center. Subjects were asked whether they consume each of 20 foods and whether these foods make their RA symptoms better, worse, or unchanged. Semi-annual registry data include demographics, medications, comorbidities, and disease activity scores. Fisher's exact and Wilcoxon rank-sum tests evaluated associations between subject characteristics from the most recent registry assessment and change in RA symptoms from specific foods.
Results
Among 217 subjects (72% response rate), 83% were female, median RA duration was 17 years (IQR 9-27), and 58% were using a biologic DMARD. Twenty-four percent of subjects reported that foods affect their RA, with 15% reporting improvement and 19% worsening. Blueberries and spinach were the foods most often reported to improve RA symptoms, while soda with sugar and desserts were most often reported to worsen RA symptoms. Younger age and noting that sleep, warm room temperature, and vitamin/mineral supplements improve RA were each associated with reporting that foods affect RA symptoms. Medication use, sex, body mass index, smoking, disease duration, disease activity scores, and self-reported RA flares were not associated with reporting that foods affect RA.
Conclusion
Nearly one-quarter of RA subjects with longstanding disease reported an effect of diet on their RA symptoms.