Women who consume large amounts of tea have increased risk of rheumatoid arthritis

So tea helps prevent some diseases and helps increase others. Not hard to believe, since it appears to affect the immune system. Immune factors have the same effect, helping in some areas, hurting in others.

http://www.eurekalert.org/pub_releases/2010-06/elar-wwc061710.php

Public release date: 18-Jun-2010
Contact: Caroline Butt
European League Against Rheumatism
Women who consume large amounts of tea have increased risk of rheumatoid arthritis
Association between coffee consumption and RA not found

Rome, Italy, Friday 18 June 2010: Women who drink tea have an increased risk of developing Rheumatoid Arthritis (RA) compared with those who drink none (p=0.04), according to results presented today at EULAR 2010, the Annual Congress of the European League Against Rheumatism in Rome, Italy. Further results from the same study showed no correlation between the amount of coffee consumption and RA incidence (p=0.16).

The results of the US based longitudinal cohort study involving 76,643 women showed a positive association of incident RA in tea drinkers with an increasing Hazard Ratio (HR) observed alongside tea consumption (p=0.03). Consuming any amount of tea carried a significant risk of developing RA (HR 1.40 (95%CI 1.01-1.93) p=0.04) and women who drank ≥4 cups of tea per day had an increased risk of developing RA compared to those who drank none (HR 1.78 (95%CI 0.83-3.82)). An analysis of the method of preparation of coffee (filtered vs unfiltered) and presence or lack of caffeine in the beverage did not show any significant associations with RA or Systemic Lupus Erythematosus (SLE, an autoimmune disease in which the immune system harms the body's own healthy cells and tissues) (RA: filtered p=0.08, unfiltered p=0.38, SLE: filtered p=0.74, unfiltered p=0.97). No increase was shown in the risk of developing RA in participants who drank coffee compared to those that did not (RA: HR 1.09 (95%CI 0.77-1.54 p=0.63).

"We set out to determine whether tea or coffee consumption, or the method of preparation of the drinks was associated with an increased risk of RA or SLE – it is surprising that we saw such differences in results between tea and coffee drinkers," said Professor Christopher Collins, Assistant Professor of Medicine, Georgetown University Medical Center, Washington, USA. "This does make us wonder what it is in tea, or in the method of preparation of tea that causes the significant increase in risk of developing RA."

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