Researchers have found yet another reason to go vegan: A plant-based, gluten-free diet seems to offer people with rheumatoid arthritis welcome pain relief.

A study based at the rheumatology unit of Sweden's Karolinska Institutet has demonstrated that switching to a vegan, gluten-free diet appears to make beneficial changes to the immune system which slows down the spread of the disease. The swelling and pain associated with rheumatoid arthritis is caused by the immune system attacking the lining of the joints.

Researchers compared the number of swollen joints found in 28 patients on a normal diet, with 30 patients who were instructed to eat only vegan, gluten-free foods. They found a reduction in the number of swollen joints in those who switched to the plant-based regimen for three months or more. There was also a large drop in the level of a chemical in the blood called CRP, which doctors use to measure inflammatory activity in the body.

After twelve months, the patients placed on the plant-based diet, also had a lower body mass index, lower cholesterol levels and higher amounts of immune system factors that can potentially inhibit inflammatory reactions.