Oral Presentation 49th Nutrition Society of Australia Annual Scientific Meeting 2025

Does adiposity mediate the relationship between diet quality and pain? (129929)

Susan J Ward 1 2 , Alison M Coates 1 3 , Sharayah Carter 1 3 4 , Katherine L Francis 3 , Ty E Stanford 1 3 , Carolyn Berryman 3 5 , Tasha R Stanton 3 5 6 , Jonathan D Buckley 1 3 , Alison M Hill 1 2
  1. Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA, Australia
  2. Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
  3. Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
  4. School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT University), Melbourne, Victoria, Australia
  5. Innovation, IMPlementation And Clinical Translation (IIMPACT), University of South Australia, Adelaide, South Australia, Australia
  6. Persistent Pain Research Group, Hopwood Centre for Neurobiology, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia

Weight loss may improve chronic musculoskeletal pain (CMP), possibly via reduced mechanical loading and lessening of systemic inflammation associated with excess adiposity (1,2). Strategies to achieve weight loss include energy restriction, but this may involve detrimental dietary practices that restrict foods or nutrients and therefore reduce the quality of the diet (3). The potential for diet to modulate CMP is an emerging area of interest, particularly given interrelationships between diet and weight. Consequently, this study aimed to determine whether improved diet quality alleviates CMP directly, or indirectly through weight loss and reduced adiposity. This secondary analysis included 104 Australian adults (aged 25–65 years; BMI 27.5–34.9 kg/m²) who participated in a 3-month dietary weight-loss intervention and had complete data for diet, weight, and pain. Measures at baseline and after 3-months included diet quality (Dietary Guideline Index [DGI]), presence of CMP, pain-related quality of life (Short-Form-36 Bodily Pain Scale [SF36-BPS]), pain severity (McGill Pain Questionnaire [MPQ]), and adiposity indicators (body weight, waist circumference [WC], body fat percentage [BF]). Linear mixed models were used to estimate the intervention's effect on these outcomes. Structural equation modelling mediation analyses explored the direct effect of changes in diet quality on CMP, plus the extent to which changes in adiposity (weight, WC, BF) mediated these relationships. Participants completing the intervention improved their diet quality (DGI total score) by 22% (p < 0.001) and lost an average of 7.1 ± 0.3 kg (95% CI -7.7, -6.4), equivalent to ~8% of their body weight. Presence of CMP decreased from 50% to 24% (p < 0.001), with significant improvements in pain-related quality of life (SF36-BPS, +6.9 ± 2.1, 95% CI, 2.7, 11.1), and reductions in pain severity at the site identified as most troublesome, and when identical (matched) pain sites were assessed (MPQ, -3.3 ± 0.8, 95% CI, -5.0, -1.7, and -3.5 ± 0.9, 95% CI, -5.3, -1.8, respectively). Structural equation modelling showed improved diet quality was directly associated with lower pain severity, when accounting for reductions in WC (β = -0.085, 95% CI -0.151, -0.019) and BF (β = -0.073, 95% CI -0.135, -0.012). Additionally, there was a direct relationship between DGI core scores and site-matched MPQ scores, independent of changes in WC (β = -158, 95% CI -0.314, -0.002). Reductions in weight, WC, or BF did not mediate the observed improvements in pain outcomes. In conclusion, a 3-month dietary intervention for weight loss improved both diet quality and pain outcomes, but these improvements were not mediated by changes in adiposity. Findings highlight the importance of diet quality for CMP management and underscore the need for further research to inform the development of targeted dietary strategies to reduce CMP independent of weight loss.

  1. Robson EK, Hodder RK, Kamper SJ, O'Brien KM, et al. (2020) J Orthop Sports Phys Ther 50, 319-333
  2. Messier SP, Mihalko SL, Legault C, Miller GD, et al. (2013) JAMA 310,1263-1273
  3. Hill EB, Cubellis LT, Wexler RK, Taylor CA, Spees CK (2023) J Am Heart Assoc12, e026777