The generation of excess free radicals and/or a deficiency in antioxidant status may play a pathophysiological role in numerous illnesses including fibromyalgia. Research has shown that FM patients have signs of increased oxidative stress as measured by protein peroxidation. In addition, decreased levels of red blood cell magnesium, plasma selenium, and thiols (essential in antioxidant handling of free radicals), have been observed. Magnesium deficiency results in the loss of red blood cell glutathione, selenium is involved in glutathione peroxidase activity, and thiols are a class of organic sulfur derivatives (including glutathione and alpha Lipoic acid) that act as reducing agents.
Diet can have a profound effect on antioxidant levels in the human body. The effect of a vegetarian diet on antioxidant levels has been the source of considerable research in recent years. Plasma total antioxidant status can be significantly increased in people following a vegetarian diet and after consuming a meal high in fruits and vegetables. Vegetarian diets are associated with increased magnesium intake and glutathione levels.
The first objective findings that indicate a vegetarian diet may benefit fibromyalgia patients come from a 1993 study published from the University of Oslo, Norway. They placed fibromyalgia patients on a 3-week vegetarian diet and measured peroxide levels, plasma fibrinogen, and serum lipid before and after the diet. At the end of the study, there was a decrease in serum cholesterol that was positively correlated with reduction in body weight, mean serum peroxide levels fell, and mean plasma fibrinogen levels decreased, and subjectively, seven of ten fibromyalgia patients reported an increase in health status in the form of improved well-being and reduced pain.
More recently, there have been three published studies examining the role of the vegetarian or vegan diet in the treatment of fibromyalgia. The first study (Hanninen et al., 2000) addressed the potential role of antioxi9dants from a vegan diet in fibromyalgia and rheumatoid arthritis (RA). The University of Kuopio, Finland, researchers examined living foods (LF), a type of vegan diet consisting of fruits, vegetables, seeds, sprouts, and nuts. The results of this study showed that significantly higher levels of serum carotenoids (lutein, lycopene, alpha carotene, and beta carotene) and flavonols (quercetin, kaempherol, and myricetin) were found in the LF groups fibromyalgia patients who consumed the LF diet reported significant improvements in joint stiffness, pain, and general health. The authors attribute the beneficial effect of the LF diet to the increased antioxidant and lignin levels as well as to the positive change in intestinal micro flora.
Researchers in Finland also investigated the effect of a 3-month uncooked vegan diet on fibromyalgia symptoms. Again, the diet was understood to be rich in lactobacilli based on the findings of the previous LF investigators. Those on the vegan diet reported a significant decrease in pain and morning stiffness and improvement in sleep quality and general health. Patients in the vegan diet intervention group also lost weight over the 3-month trial. Prior to commencing the diet, 50% of the fibromyalgia patients had a body mass index (BMI) of 25 and greater, but after 3 months on a vegan diet, all had a BMI below 24.
The most recent investigation into a raw vegetarian diet also had beneficial results (Donaldson, Speight, & Loomis, 2001). All subjects in this study were fibromyalgia patients who participated in a dietary intervention using a mostly raw, pure vegetarian diet. Subjects were instructed to consume fresh fruit, salad, raw vegetables, carrot juice, nuts, seeds, whole grains, tubers, flax seed oil, and extra virgin olive oil. They were instructed to avoid alcohol, caffeine, corn syrup, dairy, eggs, all meat, refined sugar, and hydrogenated oils and were given an unlimited quantity of dehydrated barley grass powder (Barley Green). A live instructional or video presentation was made available to all subjects. No further motivational encouragement was given. Validated instruments such as the Fibromyalgia Impact Questionnaire (GIQ) and the SF-36 Health Survey were used in follow-up assessment.
Twenty subjects returned surveys as requested over the course of the 7-month trial. A 33% improvement was noted in FIQ scores after 2 months, and this increased to 46% after 7 months. Quality-of-life scores increased over the course of the intervention, particularly in the areas of recreation, health, socializing, and participation in organization. SF-36 results were significantly higher compared to general population norms, however, after 7 months, the general health, vitality, role emotional, and mental health scores were no longer different. Significant improvement in the areas of physical performance, exercise tolerance, flexibility, and range of motion were recorded by a physical therapist. Handgrip strength and isometric shoulder endurance did not improve.
Vegetarian and vegan diets have been and continue to be of interest to those investigating other rheumatic disorders. Previous studies have shown that vegetarian or vegan diets can be of value in reducing RA symptoms. Most recently, a 1-year controlled study involving RA patients showed that a vegan diet (free of gluten) improved symptoms, possibly related to a diminished immune response to exogenous food antigens. The combined studies suggest that changes in the gut immune system can influence the course of rheumatic symptoms.
By Deirdre Rawlings, ND, PhD, MH, CNC.