This study was performed in 1000 adult Italian subjects to focus on the effects of dietary calcium intake on bone health. A higher fracture risk appears to be associated with a reduced calcium intake. An adequate daily calcium intake is recommended to counteract osteoporotic fractures.
Purpose: The principal aim of the present study was to focus on the effects of dietary calcium intake on bone mineral density (BMD) and fragility fractures in a representative sample of an adult Italian outpatient population.
Methods: The study group consisted of 1000 consecutive adult Italian subjects [838 women (F) and 162 men (M)] referred to the Bone Metabolic Diseases Unit for the evaluation of their bone metabolism. Daily dietary calcium intake was assessed using a specific food frequency questionnaire (FFQ). Other evaluations included fracture risk, lumbar and femoral BMD, heel ultrasound, fragility fractures, plasma concentration of parathyroid hormone ([PTH]) and 25-hydroxy-vitamin D ([25(OH)D]), and urinary calcium.
Results: Only 10.4% of the subjects (n = 104; 71 F and 33 M) had a daily calcium intake adequate for adults (≥1000 mg/day). No correlation was found between calcium intake and BMD. The transition from a daily dietary calcium intake <400 mg/day to a daily dietary calcium intake ≥400 mg/day was associated with a reduced fracture probability ratio at any site [from 42 to 21% (p < 0.05)]. Subjects with one or more vertebral fractures had a significantly lower dietary calcium intake (<400 mg/day) than did subjects without vertebral fractures, and they practiced physical activity only occasionally (p = 0.030).
Conclusions: Daily dietary calcium intake is lower than the recommended daily intake in an Italian ambulatory population, and a higher fracture risk appears to be associated with a reduced calcium intake. An age-adequate daily calcium intake, combined with regular physical activity, is strongly recommended in order to counteract fragility fractures.
Keywords: Bone mineral density; Calcium intake; Fragility fractures; Physical activity.