Mediterranean dietary pattern and bone mineral density: a systematic review and dose-response meta-analysis of...

We aimed to systematically review the literature and test the dose-response relationship between adherence to the Mediterranean diet (MedDiet) and values of bone mineral density (BMD) in adults.

Relevant observational studies were selected through searching PubMed, Scopus, and Web of Science databases up to March 4, 2021. A random-effects dose-response meta-analysis was performed to estimate the change in total and regional-specific BMD for a 2-point increment in the score of adherence to the MedDiet, and to clarify the shape of these associations.

Seven cross-sectional and one cohort studies with a total number of 13,209 participants were included in the final analyses. Each 2-point increment in the score of adherence to the MedDiet was associated with 0.009 (95% CI: 0.002, 0.016; I² = 34%, n = 7), 0.006 (95% CI: 0.001, 0.012; I² = 34%, n = 7), 0.005 (95% CI: 0.003, 0.007; I² = 1%, n = 4), 0.005 (95% CI: 0.002, 0.008; I² = 0%, n = 3), and 0.007 (95% CI: 0.005, 0.009; I² = 0%, n = 4) gr/cm² higher BMD of lumbar spine, femoral neck, hip, trochanter, and whole body, respectively. There was a positive linear relationship between the MedDiet adherence score and BMD of hip and trochanter. A nonlinear relationship was seen for lumbar spine, femoral neck, and whole body, with sharper increase in the BMD at lower MedDiet scores. The associations remained significant after controlling for important confounders including body weight, physical activity, smoking status, and energy intake.

Greater adherence to the MedDiet was associated with a small but important increase in BMD at the lumbar spine, femoral neck, hip, trochanter, and whole body. Adopting a Mediterranean-style eating pattern may have modest beneficial effects on bone health.