Chronic pain affects approximately 20% of adults worldwide and is a leading cause of disability. Emerging evidence suggest that nutrition may influence pain perception. However, the association between dietary quality and various pain conditions remains underexplored. This study examines associations between multiple dietary indices and the presence of acute and chronic pain analysing data from 55,721 UK Biobank participants. Multinomial logistic regression models were used to assess associations between diet quality (Dietary Inflammatory Index [DII], Healthy Diet Index [HDI], Healthful Plant-Based Diet Index [hPDI], Mediterranean Diet Score [MDS], and Eat-Lancet Diet Score [EATL]) and presence of acute or chronic pain versus pain-free individuals. Subgroup analyses examined chronic pain by number of pain sites and pain types. In fully adjusted models, higher hPDI (OR: 0.993, 95% CI: 0.989-0.997), EATL (OR: 0.969, 95% CI: 0.955-0.983), and MDS (OR: 0.981, 95% CI: 0.969-0.992) scores were positively associated with lower odds of having chronic pain, whereas only hPDI was linked to lower odds of having acute pain. Subgroup analyses showed that hPDI and EATL were consistently associated with lower odds of MSK and more localised pain while lower MDS and higher DII scores were positively associated with increased odds of widespread and non-MSK pain. This population-based study demonstrates an association between diet quality and chronic pain and extends the existing literature by showing that multiple dietary indices capture distinct aspects of this relationship. The results highlight the importance of considering different dietary indices and pain subtypes when evaluating diet-pain relationships. PERSPECTIVE: This large-scale study reveals that diverse dietary patterns associate uniquely with the risk of chronic pain and its distinct subtypes. Distinct dietary indices capture unique nutritional dimensions associated with pain type and distribution, underscoring the importance of diet and precision in understanding and managing chronic pain.

Background: Fibromyalgia is a chronic pain condition characterised by altered pain processing, widespread pain, and symptoms including sleep disturbance, fatigue, and psychological distress. Emerging evidence suggests that modifiable multimodal lifestyle factors may influence inflammation and pain mechanisms; however, the relationships between multimodal lifestyle factors, systemic inflammatory biomarkers, and pain processing remain poorly understood. In this study we aimed to investigate the associations between lifestyle factors, inflammatory biomarkers, and experimental and clinical pain outcomes in women with fibromyalgia. Methods: Women with fibromyalgia were invited to participate in this exploratory cross-sectional study. Lifestyle factors included diet, perceived stress, sleep, physical activity, heart rate variability, and BMI. Plasma IL-6, IL-10, and TNF-α were measured. Pain outcomes included quantitative sensory testing and patient-reported outcome measures. Spearman’s rank correlations and multiple linear regression analyses adjusted for age and disease duration were performed. Bootstrap 95% confidence intervals were calculated for all estimates, and False Discovery Rate (FDR) corrections using the Benjamini–Hochberg procedure were applied as a sensitivity analysis. Results: Twenty patients were included. Correlation analyses demonstrated that higher perceived stress was strongly associated with greater fibromyalgia impact (r = 0.68, p < 0.001, n = 20), central sensitization (r = 0.67, p < 0.001, n = 20), and current pain intensity (r = 0.64, p = 0.002, n = 20). A more pro-inflammatory diet was positively associated with IL-6 (r = 0.46, p = 0.04, n = 20) and IL-10 (r = 0.47, p = 0.10, n = 13), while higher TNF-α concentrations were associated with lower pressure pain thresholds (overall; r = −0.55, p = 0.021, n = 19; tibialis: r = −0.57, p = 0.010, n = 19). Following adjustment for age and disease duration, associations between stress and fibromyalgia impact, central sensitization, and current and worst pain intensity, together with associations between pro-inflammatory diet and IL-6 and IL-10, and between BMI and IL-10 showed similar directions and effect estimates. However, following FDR adjustment as a sensitivity analysis, no associations retained statistical significance. Conclusions: This study suggests that different modifiable lifestyle factors may be associated with distinct aspects of pain and inflammatory processes in women with fibromyalgia. Perceived stress showed the most consistent associations with pain-related outcomes, while dietary inflammatory potential showed preliminary associations with inflammatory biomarkers that need further investigation.