What dietary pattern and specific nutritional recommendations should be advised for a patient with rheumatoid arthritis as an adjunct to disease‑modifying therapy?

Dietary Management of Rheumatoid Arthritis

Primary Recommendation

Adopt a Mediterranean-style diet as the evidence-based dietary pattern for rheumatoid arthritis management, as it is the only diet conditionally recommended by the American College of Rheumatology with demonstrated benefits in reducing pain and inflammation. 1, 2

Core Mediterranean Diet Components

The Mediterranean diet should include the following specific elements:

• High intake of vegetables, fruits, whole grains, nuts, and seeds as foundational components that provide anti-inflammatory and antioxidant properties 1, 2

• Extra virgin olive oil as the primary fat source rather than other cooking oils or saturated fats 2

• Oily fish rich in omega-3 fatty acids consumed 3 portions per week (such as salmon, mackerel, sardines) to reduce inflammation and joint pain 2, 3

• Moderate amounts of low-fat dairy products if tolerated by the patient 1

Foods to Strictly Limit or Avoid

The following dietary components worsen RA symptoms and should be minimized:

• Added sugars and sugar-sweetened beverages should be limited as they exacerbate RA symptoms 2

• Highly processed foods, refined carbohydrates, saturated fats, and trans fats must be strictly limited or avoided due to their negative impact on both RA symptoms and cardiovascular health 1, 2

• Sodium/salt intake should be reduced to decrease cardiovascular risk, which is already elevated in RA patients 2

• High-fat, high-sugar, and high-salt dietary patterns contribute to RA progression and should be avoided 4

Mechanism of Benefit

The Mediterranean diet works through multiple pathways:

• Anti-inflammatory and antioxidant properties that directly target the inflammatory pathways involved in RA 2, 4

• Restoration of healthier gut microbiome composition, which is altered in RA patients and contributes to disease activity 2

• Omega-3 fatty acids from fish consistently demonstrate improvement in symptoms and reduction in NSAID usage 3

Diets NOT Recommended

The American College of Rheumatology conditionally recommends against other formally defined diets including ketogenic, paleo, gluten-free, vegetarian, vegan, intermittent fasting, elemental, elimination, and raw food diets due to very low to moderate certainty evidence showing no consistent, clinically meaningful benefit for RA management 2, 5

One study showed that an elimination diet avoiding meat, gluten, and lactose reduced pain and inflammation markers after 3 months 6, but this contradicts the guideline recommendations and represents lower-quality evidence compared to the systematic guideline review.

Supplements: Food First Approach

• A "food first" approach is strongly recommended over dietary supplements, as supplements show no consistent, clinically meaningful benefit for physical function, pain, or disease activity specific to rheumatoid arthritis 1, 2, 5

• Dietary supplements should only be used when necessary to correct documented nutritional deficiencies, not as primary interventions 2, 5

• The exception is that dietary fiber, probiotics, and vitamins obtained through whole foods may help reduce inflammation and relieve joint pain 4

Weight Management

• Maintaining a healthy body weight is unanimously supported for optimizing RA outcomes 1, 2, 5

• Obesity is associated with higher disease activity, impaired physical function, and poorer treatment response in rheumatoid arthritis 1, 2, 5

Interprofessional Care

• Involve a registered dietitian as part of the interprofessional care team for patients wishing to modify their diet to ensure proper implementation and nutritional adequacy 1, 5

Critical Adjunct Lifestyle Factors

Beyond diet, the following are essential:

• Smoking cessation is critical for RA outcomes and should be addressed immediately 1, 2, 5

• At least 150 minutes/week of moderate or 75 minutes/week of vigorous aerobic activity is recommended 2

• Stress management using cognitive behavioral therapy approaches can improve outcomes 2

Common Pitfalls to Avoid

• Do not recommend dietary changes as replacements for standard pharmacological DMARD therapy—diet is adjunctive only 5

• Do not recommend expensive or burdensome supplement regimens when evidence shows no benefit 1, 2

• Do not endorse vegan or other restrictive diets despite patient interest, as they lack evidence for RA-specific benefits and may lead to nutritional deficiencies 2, 5

• Do not overlook cardiovascular risk reduction, as RA patients have elevated cardiovascular disease risk that the Mediterranean diet specifically addresses 1, 2