Because the gastrointestinal symptoms reported by fibromyalgia patients are often similar to those of people with gluten sensitivity, a study compared the effects of two diets — one gluten-free and the other a low-calorie plan called the hypocaloric diet — in alleviating the discomfort experienced by FM patients.
The pilot study, conducted by researchers in Spain, found both diets of similar benefit in easing symptoms — implying that dietary changes may be of help, regardless of whether those changes remove gluten entirely or lower across-the-board the amount of calories a patient ingests each day.
The study, “The Effects of a Gluten-free Diet Versus a Hypocaloric Diet Among Patients With Fibromyalgia Experiencing Gluten Sensitivity–like Symptoms: A Pilot, Open-Label Randomized Clinical Trial,” was published in the Journal of Clinical Gastroenterology.
Gastrointestinal-associated symptoms in fibromyalgia patients are often linked to a secondary disorder called irritable bowel syndrome (IBS). But many symptoms cannot be fully explained by IBS, including abdominal pain, bloating, sour taste, abdominal gas, and nausea — all of which resemble those seen in patients with gluten-related disorders.
This suggests that gastrointestinal manifestations in fibromyalgia may be due to hypersensitivity to chemicals and food components, all of which can be altered through changes in diet.
To test this hypothesis, researchers at the University of Granada, conducted a study. Over a two-year period, from 2012 until 2014, a total of 75 patients with fibromyalgia and at least five symptoms mimicking a gluten sensitivity were randomized to either a gluten-free diet (GFD) or a hypocaloric diet (HCD, a diet in which you eat fewer calories than you burn off) for up to 24 weeks.
As a primary goal, the study evaluated the impact of each diet on the number of symptoms reported that suggested gluten sensitivity. Secondary goals were assessments of the patients’ overall health while on a restrictive diet, and a diet’s impact on mental health, body mass index, sleep quality, and fibromyalgia symptoms.
The researchers found that both diets improved the number of gluten-like sensitivity symptoms experienced, and lowered the severity of fibromyalgia symptoms. However, these beneficial effects did not differ between the two diet regimens, suggesting that gluten was not the element responsible for the gastrointestinal problems.
In addition, both diets lead to a clinically meaningful improvement of overall fibromyalgia impact scores (measured using FIQR, the revised fibromyalgia impact questionnaire), indicative of improvement in fibromyalgia symptoms.
“Gastrointestinal symptoms are highly prevalent among patients with fibromyalgia. The adoption of a GFD in our study was associated with beneficial outcomes in reducing symptoms related to gluten sensitivity; however, the nonsignificant differences in these outcomes compared with an HCD suggest the lack of any specificity of this diet,” the researchers wrote.
“Therefore, our results do not support the generalized use of a GFD in patients with fibromyalgia experiencing gastrointestinal manifestations,” they added.
Both diets were also well-tolerated by patients in the study.