Decaf coffee associated with increased risk of rheumatoid arthritis

Coffee, tea, and caffeine consumption and risk of rheumatoid arthritis: results from the Iowa Women's Health Study.

 http://www.ncbi.nlm.nih.gov/pubmed/11817612

CONCLUSIONS:

Decaffeinated coffee intake is independently and positively associated with RA onset, while tea consumption shows an inverse association with disease onset. Further investigations of decaffeinated coffee and tea intake as arthritis risk factors are needed to verify these findings and explore their biologic basis.

Arthritis Rheum 2002;46:83-91.