A very low-calorie ketogenic diet can be beneficial in women with fibromyalgia and obesity

Recently, a novel dietary strategy known as the Very Low-Calorie Ketogenic Diet (VLCKD) has been proposed as a viable treatment option for certain disorders that have similarities with fibromyalgia (FM) in terms of their clinical and pathophysiological characteristics. According to a recent study published in Frontiers in Nutrition, a 20-week VLCKD program in FM patients with obesity was associated with an immediate and positive impact on numerous functional and psychosocial aspects of the disease. 

From January 2022 to March 2023, Dr. Ciaffi and colleagues conducted a trial at IRCCS Istituto Ortopedico Rizzoli in Bologna, Italy, involving 20 women who had fibromyalgia (FM) and a BMI ≥ 30 kg/m². The study period consisted of two phases: the ketogenic phase from week 0 to week 8 (T0 to T8) and the progressive reintroduction of carbohydrates from week 8 to 20 (T8 to T20). During the initial phase of VLCKD treatment, all patients experienced weight loss, which was maintained by the time T20 arrived. On average, BMI reduced from 37.2 kg/m² at T0 to 34.8 kg/m² at T4, 33.5 kg/m² at T8, and finally to 32.1 kg/m² at T20 (P < 0.001). Additionally, there was a notable decrease in the mean Fibromyalgia Impact Questionnaire (FIQ) score from 61.7 at T0 to 37.0 at T4 and 38.7 at T8 (P < 0.001), and this improvement was sustained at T20 with a mean FIQ of 39.1 (P = 0.002). Positive outcomes were also observed in the Hospital Anxiety and Depression Scale (HADS), EuroQol 5D (EQ-5D), and 36-item Short Form Health Survey (SF-36). When analyzing each patient individually, the reduction in FIQ was clinically significant for 16 patients (89%) at T4, 13 patients (72%) at T8, and 14 patients (78%) at T20. In terms of safety, any adverse effects were mild and temporary, and no major safety concerns were identified. 

The ketogenic diet (KD) restricts carbohydrates to only 5-10% of the daily calorie intake, with the goal of altering the body’s metabolism to use ketone bodies. Numerous studies have demonstrated promising results of the KD in aiding weight loss, reducing insulin requirements in diabetes, complementing cancer treatments, managing neurological conditions, and enhancing control of metabolic and cardiovascular diseases. 

The present study suggests the effectiveness of VLCKD in patients with fibromyalgia. Further research is necessary to confirm the positive results and the high retention rate obtained in the present study, given the heterogeneity and complexity of FM. Prospective studies with larger sample sizes and longer follow-up periods are needed to gain a deeper understanding of the potential applications of VLCKD in tailoring treatment approaches for FM patients. 


  1. Ciaffi J, Lisi L, Mari A, Mancarella L, Brusi V, Pignatti F, et al. Efficacy, safety and tolerability of very low-calorie ketogenic diet in obese women with fibromyalgia: a pilot interventional study. Front Nutr. 2023;10:1219321.  
  2. Ciaffi J, Mitselman D, Mancarella L, Brusi V, Lisi L, Ruscitti P, et al. The Effect of Ketogenic Diet on Inflammatory Arthritis and Cardiovascular Health in Rheumatic Conditions: A Mini Review. Front Med (Lausanne). 2021;8:792846.