Gluten-Free Diet Reduces Pain in Women with Myofascial Pain in Masticatory Muscles: A Preliminary Randomized Controlled Trial

Aims: To evaluate the efficacy of a gluten-free diet (GFD) as a treatment modality for pain management in women with chronic myofascial pain in masticatory muscles. Methods: In this randomized controlled trial, 39 female subjects were evaluated according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and divided into three groups: a healthy group (n = 14; mean ± SD age = 34.57 ± 9.14 years); a control group (n = 12; age = 31.50 ± 7.38 years); and an experimental group (n = 13; age 30.00 ± 7.64 years). The outcome variables were: pain intensity, mechanical pain threshold (MPT), and pressure pain threshold (PPT). MPT was performed on the masseter muscle, and PPT was performed on both the masseter and anterior temporalis muscles. A nutritionist prescribed a 4-week individualized GFD for the experimental group. The healthy group was analyzed only initially, whereas the control and experimental groups were analyzed again after 4 weeks. Data were subjected to statistical analysis with a significance level of 5% (one-way analysis of variance followed by Bonferroni post hoc, paired t, Wilcoxon signed rank, Kruskal-Wallis/Dunn, and Pearson chi-square tests). Results: Participants who underwent a GFD showed reduction in pain intensity (P = .006) and an increase in PPT of the masseter (P = .017) and anterior temporalis (P = .033) muscles. The intervention did not influence the MPT of the masseter muscle (P = .26). In contrast, the control group showed no improvement in any parameter evaluated. Conclusion: GFD seemed to reduce pain sensitivity in women with TMD and may be beneficial as an adjunctive therapy for chronic myofascial pain in masticatory muscles; however, further studies in the fields of orofacial pain and nutrition are required.

diet; diet therapy; facial pain; gluten-free; pain threshold; temporomandibular disorders

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