NEW YORK, Nov 23 (Reuters Health) -- A Mediterranean diet may help protect people against rheumatoid arthritis, Greek investigators report.
A high intake of olive oil and cooked vegetables may reduce the risk of developing the disease, according to Dr. Athena Linos, from the University of Athens Medical School, and colleagues. Their study findings are published in the American Journal of Clinical Nutrition.
In rheumatoid arthritis, the immune system reacts against the body's own tissues to cause joint swelling and pain, and eventually even the destruction of a joint. The causes remain unknown, but previous studies have suggested that dietary factors have a role in the disease.
The research team compared the diets of 145 rheumatoid arthritis patients with the diets of 188 people who did not have the disease. All of the study participants lived in southern Greece, where the average diet consists of more cooked and raw vegetables, fish and olive oil than most diets in Westernized countries, and less meat.
Linos and her colleagues found that people who used the most olive oil were significantly less likely to develop rheumatoid arthritis than people who consumed the least.
Participants who ate the greatest number of servings of cooked vegetables were about 75% less likely to develop rheumatoid arthritis than those who reported eating the fewest servings, the team determined. People with the lowest intake of cooked vegetables ate 0.85 servings of cooked vegetables a day, on average, and people with the highest intakes ate an average of 2.9 servings a day.
In contrast to other studies, which have found that supplementing the diet with fish oil improves symptoms of rheumatoid arthritis, the Greek investigators found no protective effect from a high intake of fish.
The authors point out that Mediterranean people do not normally eat the type of fish that are rich in protective fatty acids -- deep-water fish such as herring and mackerel. On the other hand, they suggest, the relatively high level of unsaturated fatty acids found in olive oil may help suppress the inflammation associated with rheumatoid arthritis, in much the same way that fatty acids in deep-water fish do.
As reported by Reuters Health, previous studies have suggested other benefits of a Mediterranean diet, including a lower risk of cancer, heart disease, and memory loss.
