What is the best diet for an adult patient with rheumatoid arthritis (RA)?

Best Diet for Rheumatoid Arthritis

A Mediterranean-style diet is conditionally recommended for adults with rheumatoid arthritis, as it has demonstrated improvement in pain symptoms with low to moderate certainty evidence. 1

Core Dietary Recommendation: Mediterranean-Style Diet

The American College of Rheumatology specifically endorses the Mediterranean-style diet over other formally defined diets for RA management. 1 This dietary pattern provides both RA-specific benefits and broader cardiovascular protection, which is particularly important given the increased cardiovascular risk in RA patients. 1

What to Eat Daily:

• Vegetables and fruits: 5 portions daily, emphasizing green leafy vegetables, berries, and citrus fruits 2
• Whole grains: 3 portions daily (preferably gluten-free options) 2
• Healthy fats: Extra virgin olive oil as the primary fat source 1, 2
• Nuts and seeds: Regular intake 1
• Low-fat dairy: 125 ml light yogurt and 200 ml skim milk daily 2
• Wine: Up to 125 ml daily if desired 2

What to Eat Weekly:

• Fish: 3 portions per week, particularly oily fish rich in omega-3 fatty acids 1, 2
• White meat: 3 portions per week 2
• Legumes: 2 portions per week 2
• Eggs: 2 portions per week 2
• Aged cheeses: 2 portions per week 2
• Red or processed meat: Maximum once per week 2

What to Strictly Limit or Avoid:

• Added sugars and sugar-sweetened beverages 1
• Sodium/salt 1, 2
• Highly processed foods 1
• Refined carbohydrates 1
• Saturated fats and trans fats 1

Why This Diet Works

The Mediterranean diet has anti-inflammatory and antioxidant properties that specifically target the inflammatory pathways involved in RA. 1 Research demonstrates that RA patients have altered gut microbiota with less beneficial bacteria and more potentially harmful species, and the Mediterranean diet helps restore a healthier gut microbiome composition. 1

What NOT to Do

Other formally defined diets (ketogenic, paleo, gluten-free, vegetarian, vegan, intermittent fasting, elemental, elimination, raw foods) are conditionally recommended against due to very low to moderate certainty evidence showing no consistent, clinically meaningful benefit for physical function, pain, or disease activity in RA. 1

Dietary Supplements: A "Food First" Approach

Following established dietary recommendations without dietary supplements is conditionally recommended over adding dietary supplements. 1 The evidence shows no consistent, clinically meaningful benefit on physical function, pain, or disease activity for supplements including vitamin D, probiotics, fish oil, omega-3 fatty acids, and antioxidants (selenium, zinc) when used specifically for RA management. 1

Important Caveats:

• Supplements may still be appropriate for bone health (vitamin D) and cardiovascular health (fish oil), which are particularly important comorbidities in RA patients 1
• If proper nutritional status cannot be achieved through diet alone, deficiencies should be corrected with appropriate supplementation 1
• Folic acid supplementation remains important for patients on methotrexate (covered in pharmacologic guidelines) 1

Weight Management

Maintaining a healthy body weight is unanimously supported for optimizing RA outcomes. 1 Obesity is associated with higher disease activity, impaired physical function, and poorer treatment response in RA. 1 While specific weight loss interventions weren't formally recommended, clinicians should engage in discussions about healthy weight maintenance. 1

Role of the Registered Dietitian

The expert role of a registered dietitian as a member of the interprofessional care team is specifically recognized for patients wishing to modify their diet. 1 This is particularly important given the burden and costs of adhering to dietary changes, and the need for individualized nutritional counseling. 1

Additional Lifestyle Factors

Beyond diet, patients should receive counseling on: 1

• Smoking abstention: Critical for RA outcomes 1
• Physical activity: At least 150 minutes/week of moderate or 75 minutes/week of vigorous aerobic activity 1
• Stress management: Using cognitive behavioral therapy approaches 1

Common Pitfalls to Avoid

• Don't recommend restrictive elimination diets without evidence of specific food allergies or intolerances 1
• Don't rely on supplements as primary therapy when dietary modification can achieve the same nutritional goals 1
• Don't ignore the burden of dietary change on patients—the recommendation is conditional partly because adherence can be challenging 1
• Don't forget cardiovascular risk—the Mediterranean diet provides dual benefits for both RA symptoms and long-term cardiovascular outcomes 1