Ingested Intolerances and Toxins-Physical:  Research Article

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Fibromyalgia Symptoms and Dietary Excitotoxins

CITATION:  Smith, J. D., Terpening, C. M., Schmidt, S., & Gums, J. G. (2004). Relief of fibromyalgia symptoms following discontinuation of dietary excitotoxins. Annals of Pharmacotherapy, 35(6) 702-706.


Background: Fibromyalgia is a common rheumatologic disorder that is often difficult to treat effectively.

Case Summary: Four patients diagnosed with fibromyalgia syndrome for two to 17 years are described. All had undergone multiple treatment modalities with limited success. All had complete, or nearly complete, resolution of their symptoms within months after eliminating monosodium glutamate (MSG) or MSG plus aspartame from their diet. All patients were women with multiple comorbidities prior to elimination of MSG. All have had recurrence of symptoms whenever MSG is ingested.

Discussion: Excitotoxins are molecules, such as MSG and aspartate, that act as excitatory neurotransmitters, and can lead to neurotoxicity when used in excess. We propose that these four patients may represent a subset of fibromyalgia syndrome that is induced or exacerbated by excitotoxins or, alternatively, may comprise an excitotoxin syndrome that is similar to fibromyalgia. We suggest that identification of similar patients and research with larger numbers of patients must be performed before definitive conclusions can be made.

Conclusion: The elimination of MSG and other excitotoxins from the diets of patients with fibromyalgia offers a benign treatment option that has the potential for dramatic results in a subset of patients.


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