Best estimate of what happens to people with rheumatoid arthritis:
Pain (higher scores mean worse or more severe pain):
-People who took eveing primrose oil, primrose oil, borage seed oil, or blackcurrent seed oil (wih the active ingredient GLA) rated their pain to be 33 points lower (9 to 56 points lower) on a scale of 0 to 100 after 6 months of treatment (33% absolute improvement).
-People who took placebo rated their pain to be 19 points lower after treatment.
Physical function (higher score means greater disability):
-People who took GLA rated their disability 16% better.
-People who placebo rated their disability 5% better.