Search

Unlabelled: INTRODUCTION--HYPOTHESIS: Since the genetic bases of bone mass regulation in males are still poorly understood and the role of calciotropic hormones on bone mineral metabolism is absolute, our hypothesis is based on the certainty that specific genetic polymorphism will contribute, at least, on bone mass values. Our objective was to examine the relative contribution of genetic variables to the regulation of bone values in a population of young healthy men, focusing on the BsmI polymorphism of vitamin D receptor (VDR) gene and the AluI polymorphism of calcitonin receptor (CTR) gene., Methods: Areal bone mineral density (aBMD), bone mineral content (BMC) and geometrical areas at specific skeletal sites of the forearm, of 301 healthy Caucasian young men, aged 18-25, were assessed by single X-ray absorptiometry (Osteometer DTX-100). VDR and CTR alleles were determined by BsmI and AluI endonuclease restriction fragment analyses. Analysis of covariance was used as a statistical model., Results: No significant differences in the forearm aBMD, BMC or in area values were observed between the VDR and CTR genotypes. Findings did not change after adjusting for demographic characteristics., Conclusions: The BsmI and AluI polymorphisms are not related to the forearm bone values either reflecting mass or geometrical variables in this male population.

Objective: The aim of this study was to evaluate the effects of dietary factors (calcium, proteins, alcohol, coffee and tea intake), exercise, sunlight exposure and immobilization on bone mineral content (BMC) and bone mineral density (BMD) in young men., Patients and Measurements: We examined a group of 300 healthy men, aged 18-30. Mean weight was 80-81 kg (53-125 kg range) and height 179 cm (160-195 cm range). Distal BMC (dBMC), distal BMD (dBMD) and ultradistal BMD (udBMD) at the radius were measured by single X-ray absorptiometry (Osteometer DTX). The data concerning lifestyle factors were obtained through a questionnaire. The 300 men were divided in four groups according to calcium intake, four groups taking into account protein and three groups alcohol intake. There also were five groups of exercise level, six groups of sun exposure and two groups of duration of immobilization., Results: In the group with the lowest levels of calcium intake (< 400 mg/day), dBMD and udBMD were lower than in the other groups of calcium intake (P = 0.002). dBMC and udBMD were lower (P = 0.043 and 0.015, respectively) in subjects with low physical activity (< 2 h/week), whereas dBMC and udBMD were higher (P < 0.0005) in subjects with frequent sun exposure (group labelled 'very often'). Multiple regression analysis on bone mineral density of the forearm showed that, calcium intake, exercise and sunlight were also independent predictors of bone mass. No significant correlation between the other examined factors and BMD or BMC was detected., Conclusions: Calcium intake, exercise level and sun exposure showed a statistically significant correlation with distal BMD and BMC in young adult men.