Blackcurrant seed oil trials for rheumatoid arthritis
In the first RCT, two groups of participants were randomly selected to receive one of the following treatments daily for 24 weeks:
- One group (14 participants) was given 10.5 g blackcurrant seed oil.
- The other group (20 participants) received placebo capsules made from soybean oil for the same period of time.
All participants were asked to continue their usual diets and medications.
- Only 50% of participants in the blackcurrant seed oil capsules completed the trial. The two main reasons for stopping the medication were:
1. the large amount (15 capsules) and size of the capsules
2. participants believing the treatment wasn’t effective.
- Compared to the placebo group, members of the blackcurrant seed oil group who completed the trial had:
- a significant but moderate reduction in joint tenderness
- only mild and non-significant reduction in pain, morning stiffness and overall disease severity.
- The minor side-effects of blackcurrant seed oil didn’t contribute to participants withdrawing from the trial. The nature of the side-effects wasn’t reported.
In the second RCT, participants were randomly selected to receive one of the following treatments daily for six weeks:
- One group (20 participants) were given 3 g blackcurrant seed oil (six capsules)
- The other group (10 participants) received placebo capsules made of sunflower seed oil.
The effects on morning stiffness, grip strength, pain and physical function were measured at the end of the trial and again six weeks after treatment.
- Compared to the placebo group, who showed no improvement at both assessment points, participants on blackcurrant seed oil had significant reduction in morning stiffness at the end of the treatment; however, this beneficial effect wasn’t observed six weeks after the trial had ended.
- Compared with the placebo, blackcurrant seed oil had no significant effect on improving the following at either at assessment point:
- grip strength
- physical function.