 The pro-inflammatory metabolites of arachidonic acid from animal products are involved in more than just neuro-inflammation. They also appear to play a role in cancer, asthma, rheumatoid arthritis, and other autoimmune disorders. For example, last year we discovered eating a lot of arachidonic acid may quadruple our risk of developing the inflammatory bowel disease ulcerative colitis. Anti-inflammatory effects of a lower arachidonic acid diet may help explain why patients with rheumatoid arthritis improve on a vegetarian diet. It's funny there was an arthritis study done where they put half the people on a vegetarian diet for a year, and they were saying how they were worried that for some patients it may be difficult to change from an omnivorous diet to a strict vegetarian diet. They expected some people may have felt a decreased quality of life when they had to renounce ordinary food. Furthermore, a strict vegetarian diet can put a strain on a patient's social life. Therefore, one could envisage that the psychological distress experienced by the newly vegetarian would increase during the study. On the contrary, though, they found that the patients put on the vegetarian diet had a significantly better improvement in their GHQ20 scores compared to the omnivorous patients, which is a measure of psychological health. Those eating vegetarian also became less depressed and less anxious. That was not what they expected. Now this could be a function of the vegetarians eating less arachidonic acid, but another possibility is that the patients in the vegetarian group experienced less psychological distress because of the clinical improvement. Maybe they felt better because they got better, or as they put it, it is reasonable to assume that less pain, shorter duration of morning stiffness, better grip strength, and less disability wouldn't pose less psychological distress on the patients.