Researchers at the Department of Epidemiology, University of Athens Medical School, Greece examined the relation between diet and the risk of rheumatoid arthritis (RA) in persons from southern Greece. The results of their study suggest that eating hearty amounts of cooked vegetables and olive oil may significantly reduce the risk of developing RA, a chronic inflammatory disease of the joints. The cause of RA is unknown, but genes, infectious agents, hormones, and diet have all been suggested as possible causes.
Researchers studied 145 RA patients and 188 control subjects who responded to an interviewer-administered food-frequency questionnaire that assessed their consumption of a wide variety of foods. In this study, consumption of both cooked vegetables and olive oil was found to be inversely associated with risk of rheumatoid arthritis, meaning that individuals whose diets included higher amounts of cooked vegetables and olive oil had a lower risk of developing RA. Those individuals who regularly consumed both cooked vegetables and olive oil had the lowest risk for RA.
Investigators found that people who consumed the least olive oil were 2.5 times more likely to develop rheumatoid arthritis compared to those who consumed the most of this healthful oil. Additionally, those who consumed the most cooked vegetables had a 75% lower risk of developing rheumatoid arthritis.
Although the underlying mechanisms by which cooked vegetables and virgin olive oil lower RA risk remains unclear, the authors theorize that when vegetables are cooked, the heat destroys the vegetables' cell walls, making it easier for the body to absorb their beneficial substances. They also suggest that both the antioxidant properties and high monounsaturated fatty acid content of olive oil might play a protective role.
Most people are aware of the many antioxidants in vegetables, but it is less well known that olive oil is rich in vitamin E, one of the body's most important free radical quenchers. Free radicals are destructive molecules that are involved not only in RA, but also in many chronic diseases as well as aging. Additionally, both saturated fats and vegetable oils high in omega-6 fats are used by the body to produce hormone-like substances called Series 2 prostaglandins that promote inflammation. In contrast, the monounsaturated fats in virgin olive oil are not used to create these inflammatory prostaglandins. Plus in addition to vitamin E, virgin olive oil contains polyphenolic compounds that have been shown to have both anti-inflammatory and antioxidative effects. So, when olive oil is consumed instead of these other pro-inflammatory fats, the result is a significant lessening in inflammatory processes.
For suggestions as to how to enjoy the more cooked vegetables and olive oil, truly some of the World's Healthiest Foods, click on the Recipe Assistant, select olive oil and any of the vegetables on the healthy foods list, and click on the Submit button. A list containing links to all the World's Healthiest Foods' recipes containing these foods will appear immediately below.
Linos A, Kaklamani VG, Kaklamani E, Koumantaki Y, Giziaki E, Papazoglou S, Mantzoros CS. Dietary factors in relation to rheumatoid arthritis: a role for olive oil and cooked vegetables? Am J Clin Nutr1999 Dec;70(6):1077-82.
Patrick L, Uzick M. Cardiovascular disease: C-reactive protein and the inflammatory disease paradigm: HMG-CoA reductase inhibitors, alpha-tocopherol, red yeast rice, and olive oil polyphenols. A review of the literature. Altern Med Rev 2001 Jun;6(3):248-71