Better diet quality is associated with reduced body pain in adults regardless of adiposity: Findings from the Whyalla Intergenerational Study of Health

Dietary intake has been associated with pain and physical function, but it is unclear if these relationships are mediated by adiposity. Data were derived from the Whyalla Intergenerational Study of Health (n = 654, 57% women). Structural equation modelling tested the hypotheses that adiposity (body mass index (BMI), waist circumference (WC), or body fat (BF, dual energy x-ray absorptiometry)) would mediate the relationship between diet quality (Dietary Guideline Index (DGI) total, core, or non-core scores) and pain (Short Form-36 bodily pain scale (SF36-BPS)), or physical function (grip-strength), overall, and by gender. Adiposity did not mediate a relationship between DGI scores and pain. Direct effects were observed between DGI total scores and SF36-BPS accounting for BMI (β = 0.170, 95% CI 0.002, 0.339), and between DGI core food scores and SF36-BPS (BMI, β = 0.278, 95% CI 0.070, 0.486; WC, β = 0.266, 95% CI 0.058, 0.474; BF, β = 0.266, 95% CI 0.060, 0.473). In women, direct effects existed between DGI scores and SF36-BPS (DGI total scores, BMI, β = 0.388, 95% CI 0.162, 0.613; WC, β = 0.372, 95% CI 0.146, 0.598; BF, β = 0.382, 95% CI 0.158, 0.605, and DGI core scores, BMI, β = 0.482, 95% CI 0.208, 0.757; WC, β = 0.472, 95% CI 0.197, 0.747; BF, β = 0.467, 95% CI 0.195, 0.739), and DGI total scores and grip-strength (BMI, β = 0.075, 95% CI 0.008, 0.142; WC, β = 0.076, 95% CI 0.009, 0.143; BF, β = 0.079, 95% CI 0.011, 0.146). Better diet quality is associated with lower bodily pain, irrespective of adiposity. Findings highlight the potential role of diet quality in pain management and function, particularly in women.