Increased inflammatory potential of diet is associated with bone mineral density among postmenopausal women in Iran

Diet has been shown to be associated with bone mineral density (BMD); however, the inflammatory potential of diet in modulating BMD has not yet been studied.

We examined the association between a newly developed dietary inflammatory index (DII) and BMD in a sample of postmenopausal Iranian women. In this cross-sectional study, 160 postmenopausal women aged 50-85 years were studied and their femoral neck and lumbar spine BMDs were measured by dual-energy X-ray absorptiometry. The DII was computed based on dietary intake assessed using a previously validated, 168-item semiquantitative food frequency questionnaire. Logistic and linear regression models were fit to derive beta estimates and odds ratios (ORs), with DII fit as continuous and as a dichotomous variable.

After adjusting for potential confounders, women with higher DII scores were more likely to have BMD below the median in the lumbar spine with the DII being used as both a continuous variable [ORcontinuous 1.64, 95 % confidence interval (CI) 1.11-2.43, p value = 0.01; one-unit increase corresponding to ≈17 % of its range in the current study] and a categorical variable (ORDII>-0.06/≤ 2.30, 95 % CI 1.05-5.07, p value = 0.04). Similar associations were observed when lumbar spine BMD was used as a continuous outcome. No significant association was observed with BMD in femoral neck, although the direction was along expected lines.

These data suggest a pro-inflammatory diet, as indicated by increasing DII score, may be a risk factor for lower BMD in lumbar spine in postmenopausal Iranian women.