Could Certain Foods Be Making Your Rheumatoid Arthritis Symptoms Worse?
If you live with rheumatoid arthritis (RA), you may have wondered: “Could a certain food be making my joint symptoms worse?”
As part of my PhD I carried out a scoping review titled “Elimination – Reintroduction Diets and Oral Food Challenge in Adults with Rheumatoid Arthritis” This research mapped what the evidence says about using elimination diets and food challenges in adults with RA.
Although many people with RA report that food affects their symptoms and often avoid particular foods, until now there had been no review that focused solely on studies investigating food sensitivity in RA.
What Are Elimination and Reintroduction Diets?
An elimination–reintroduction diet is one way to explore whether certain foods affect joint pain or swelling. The process involves removing potentially problematic foods for a period of time, then adding them back one at a time (or in small groups) to see whether symptoms or inflammation worsen. If a reaction is reproducible, that food may be a trigger.
A food challenge typically tests a food previously suspected of causing a reaction, often under more controlled conditions, and measures any changes in symptoms or inflammatory markers.
How the Study Was Conducted
We searched five academic databases and grey literature (including theses and conference abstracts) for studies in adults (aged ≥18 years) with RA that involved an elimination diet followed by food reintroduction or an oral food challenge.
All study designs were eligible — randomised controlled trials (RCTs), non-RCTs, and case studies.
In total, we found 20 studies and 17 case reports published between 1949 and 2024, involving between 4 and 94 participants across 12 countries. The majority were conducted between 1980 and 2000.
What Kinds of Diets and Challenges Were Used?
Most studies began with a short, very restricted elimination phase, which included one of the following approaches:
- Fasting protocols: water or juice only for 4–10 days, supervised in hospital or inpatient settings.
- Low-allergen replacement diets: a meal replacement plus a few hypoallergenic foods for about four weeks.
- Few-foods diets: highly restricted whole-food diets lasting one to four weeks, often allowing one or two protein foods (e.g. cod or lamb), a small range of vegetables, and one or two fruits, with mineral water only. Some versions were entirely plant-based.
- Single-food exclusions: for example, dairy-free diets.
Participants typically followed the restricted diet for at least a week. During this period, symptoms improved in around 70–80% of participants, though not everyone experienced benefits. Once symptoms improved, foods were reintroduced one at a time (or in groups), and reactions were observed by clinicians or the participants themselves. Reactions usually included joint pain, swelling, or stiffness, and some studies also measured laboratory markers of inflammation.
Foods were added back at varying intervals, some studies introduced three foods per day (five hours apart), while others tested one new food every two to five days. If a food caused symptoms, it was excluded again until symptoms resolved, after which another food could be tested. This process generally took four weeks to four months.
How Quickly Did Reactions Occur?
In six studies, researchers recorded how long it took for a reaction to appear.
Typically, reactions began within 1-48 hours, although 2-24 hours was most common in the case studies. Symptoms usually subsided within 24 hours to 10 days after the food was removed. This delay suggests that testing new foods every 2–3 days provides the most accurate results.
Interestingly, one study focusing solely on dairy found that participants developed joint swelling and pain only after two to three weeks of regular consumption.
In blinded food challenges, where participants did not know if they were receiving the suspected food or a placebo, some individuals still experienced worsened symptoms, suggesting a genuine physiological reaction.
A subset of participants identified foods that reliably triggered symptoms. By permanently excluding these foods, some achieved reduced disease activity, and a few were able to remain symptom-free and discontinue medication.
Which Foods Commonly Triggered Symptoms?
Ten studies and 16 case studies (involving 161 people) listed the foods that triggered symptoms and how many participants reacted to each.
When results were combined, the most frequently reported trigger foods were:
- Cereal grains: particularly wheat and corn
- Dairy products
- Eggs
- Beef and pork
- Nightshade vegetables: tomatoes and potatoes
- Sugar and caffeine/coffee
The graph below shows the cumulative food reactions from 161 people from all the studies that listed foods.
Limitations of the Evidence
Most studies had small sample sizes, many are old (before 1999), protocols were inconsistent, follow-up was limited, and outcome measures varied widely. Overall the methodological quality of studies was generally weak or unclear.
To date there are no standardised elimination-reintroduction protocols for identifying food triggers in RA, and no reliable laboratory tests that can accurately pinpoint which foods may exacerbate symptoms. The most dependable approach remains a carefully planned elimination-reintroduction diet, ideally supervised by a qualified nutrition professional.
Today the most commonly used exclusion based diets in RA include the auto-immune protocol (AIP) and various plant based approaches, like the Paddison Programme. However, only the AIP diet follows a structured elimination-reintroduction process. Most vegan or plant-based diets exclude food groups without a formal reintroduction phase.
Takeaway Message
For some people with RA, specific foods may indeed aggravate symptoms, but responses are highly individual. While research to date is limited and often outdated, the consistent finding across decades is that some individuals do experience real, reproducible reactions.
A carefully guided elimination-reintroduction diet remains the most practical and evidence-informed way to identify personal food triggers.
Here is a link to the full study, where you will find all references: Elimination reintroduction diets and oral food challenge in adults with rheumatoid arthritis: a scoping review
The supplementary data has details of all the studies investigated
An intervention using the AIP elimination-reintroduction diet is the other part of my PhD and results are currently awaiting publication.
