More Tea, Less Rheumatoid Save

A large cohort study of rheumatoid arthritis (RA) patients shows that regular tea consumption was associated with a lower risk of RA.

Tea consumption was quantified in 2237 incident RA cases (2005–2018) and 4661 controls, who were matched on age, sex, and residential area. Tea consumption was classified into no (0 cups/day), irregular (< 1 cup/day), regular (1–2 cups/day), and high (≥ 2 cups/day) consumption, and irregular consumption was used as the reference category.

In RA patients, 57.3% were ever consumers of tea and 19.7% having a high tea consumption. Similar tea use was seen in controls (58.4% ever drinkers, 22.1% high consumers).

High tea consumption was associated with a 22% lower risk of incident RA compared to irregular consumption [OR = 0.78 (95% CI 0.66–0.92)]. But statistical significance was lost in the adjusted model [adjusted OR (adjOR) = 0.85 (95% CI 0.71–1.01)].

If the population was narrowed to ACPA-positive, current smokers, a protective effect was seen for high tea consumption in both models [adjOR = 0.76 (95% CI 0.62–0.94) and adjOR = 0.60 (95% CI 0.38–0.95), respectively].

This data suggests a protective effect of high consumption of tea, primarily in smokers and ACPA-positive RA patients.

There is conflicting evidence on the effect of caffeine on the development of autoimmune disease and RA. By contrast there are studies showing that caffeine may inhibit inflammatory pathways and, thereby lessen autoimmunity.

Teas are rich in polyphenols/antioxidants that may reduce the risk of inflammation. But there are mixed results when looking a population studies and the effects of tea consumption on the risk of developing RA. While no protection was seen in the Nurse’s Health Study, the Women’s Health Initiative Observational Study and a UK study; positive protective benefits were seen in the Iowa Women’s Health Study and a case-control study from Iran.