TOPLINE:
The risk for developing rheumatoid arthritis (RA) rose with a high intake of red and processed meat vs fruits and vegetables in a case-control study.
METHODOLOGY:
- The risk of developing RA based on dietary habits was explored in a Swedish nested case-control study within a prospective study conducted between January 1991 and September 1996 (n = 28,098).
- Diet was assessed at baseline using a 7-day menu book, a 168-item questionnaire, and an interview lasting 45-60 minutes, and each RA patient was matched to four control individuals for analysis.
- Compliance with the 2015 Swedish Dietary Guidelines for intake of fiber, fruits and vegetables, fish/shellfish, added sugars, and red or processed meat was scored and categorized as low, moderate, or high.
- Data from registries and validated electronic medical records identified RA incidence through December 2016; data on rheumatoid factor and anticyclic citrullinated peptide antibody were also retrieved.
TAKEAWAY:
- A total of 305 incident cases of RA were identified (76.1% women; 66.9% seropositive), with a mean age of 56.8 years at baseline and an average 12-year interval until diagnosis.
- Consuming < 500 g/wk of red and processed meat (adjusted odds ratio [aOR], 0.60; 95% CI, 0.38-0.97) and ≥ 400 g/d of vegetables and fruits (aOR, 0.64; 95% CI, 0.43-0.94) significantly reduced the odds of developing RA.
- Lower odds of developing RA were linked to fruits and vegetables (aOR per SD, 0.70; 95% CI, 0.57-0.87) and fiber (aOR per SD, 0.80; 95% CI, 0.64-0.99) vs higher odds with red and processed meat (aOR per SD, 1.31; 95% CI, 1.07-1.59).
- Adhering to intake guidelines for all food types was linked to a lower risk for seropositive RA; higher odds were linked to higher consumption of red and processed meat (aOR, 3.43; 95% CI, 1.69-6.96).
IN PRACTICE:
“[The study] findings suggest a dose-response relationship between red/processed meat intake and the risk of seropositive, but not seronegative, RA. This study helps to improve our understanding of the effects of dietary components in RA development, particularly for red and processed meats, but the exact mechanisms behind our findings need further investigation,” the authors concluded.
SOURCE:
This study was led by Rebecka Bäcklund, Lund University, Malmö, Sweden. It was published online on July 10, 2025, in Annals of the Rheumatic Diseases.
LIMITATIONS:
The diet was assessed only at baseline. Data were retrieved from a study that examined the association between diet and cancer, which may have introduced selection bias. Dietary guidelines, especially regarding meat intake, may have changed over time.
DISCLOSURES:
This study received support from the Swedish Rheumatism Association, the Gustav V 80-year fund, the Greta and Johan Kock foundation, and others. The authors declared having no conflicts of interest.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.