This is a 8-week, double-blinded, placebo-controlled, randomized intervention trial to investigate the effects of Mg and Zn supplementation on antioxidant status and bone hormonal parameters. Participants were randomly assigned to one of three treatment groups: Placebo group (PbG: 25 women); Magnesium Group - 500 mg/day of Mg (MgG: 27 women); Zinc Group - 50 mg/day of Zn (ZnG: 26 women).
Seventy-eight healthy postmenopausal volunteers aged between 44 and 76 were recruited once had been informed about the protocol. This is a 8-week, double-blinded, placebo-controlled, randomized intervention trial to investigate the effects of Mg and Zn supplementation on antioxidant status and bone hormonal parameters. Participants were randomly assigned to one of three treatment groups: Placebo group (PbG: 25 women); Magnesium Group - 500 mg/day of Mg (MgG: 27 women); Zinc Group - 50 mg/day of Zn (ZnG: 26 women).
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
78
Oral administration of 1 daily capsule containing lactose
Oral administration of 1 daily capsule containing 50 mg/day of Zn
Oral administration of 1 daily capsule containing 500 mg/day of Magnesium
Universidad de Granada
Granada, Spain
Antioxidant status
Total antioxidant capacity (TAC) determination in plasma samples was carried out evaluating the reduction power of Cu2+ from the action of antioxidants present in samples (TAC kit, Jaica, Shizuoka, Japan). Values were expressed in umol/L.
Time frame: 2 months
Oxidative stress
Glutathione peroxidase (GPx) in mU/mL and Superoxide dismutase (SOD) in U/mL. GPx activity was determined by using the Bioxytech GPx-340™ kit (OxisResearch™), an indirect colorimetric assay of the activity of c-GPx \[28\]. SOD activity was determined by using the Randox Ransod kit (RANDOX Laboratories Ltd., United Kingdom).
Time frame: 2 months
Anthropometric assessment - Height
Values were expressed in centimeters.
Time frame: 2 months
Anthropometric assessment - Waist circumference
Values were expressed in centimeters.
Time frame: 2 months
Anthropometric assessment - Body composition by bioelectrical impedance
Body composition assessment was taken by multifrequency bioelectrical impedance (Tanita MC-980 Body Composition Analyzer MA Multifrequency Segmental, Barcelona, Spain). The analyzer complies with the applicable European standards (93/42EEC, 90/384EEC) for use in the medical industry. Participants were informed in advance of the required conditions prior to the measurement: no alcohol less than 24 hours before the measurement, no vigorous exercise less than 12 hours prior to the measurement, no food or drink less than 3 hours prior to the measurement, and no urination immediately before the measurement. All measurements were taken simultaneously during the morning in fasting conditions. The following measurements were taken: weight, body mass index (calculated as weight/height\^2 and expressed kg/m2) and fat mass (expressed in kilograms and as the percentage of body fat), fat free mass (expressed in kilograms and as the percentage of fat free mass), muscle mass (expressed in kilograms).
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: 2 months
Intake assessment
Dietary intake was performed at baseline and after two months of intervention. Nutritional assessment was quantitatively and qualitatively performed using a 72 hours' dietary record and food frequency questionnaire (FFQ). Data from food intakes were obtained in the course of individual interviews to request information from each participant about the types of foods and serving sizes. Dietary intake was compared with the daily recommended allowances (DRA). Insufficient intake levels were determined by comparing actual intakes of different nutrients with the recommended intake for each participant and were recorded as below 75% of the RDA. FFQ was used to set the information about the frequency consumption in each group of foods. FFQ was compared with the recommendations proposed by the Spanish Community Nutrition Society (SENC) and expressed as the percentage of participants below or above the recommended servings.
Time frame: 2 months
Biochemical parameters - Clinical-nutritional parameters
Biochemistry was performed after 12 hours of fasting first thing in the morning, by specialists puncturing the cubital vena cava (Venoject®). The following measurements were taken: Glucose (mg/dL), creatinine (mg/dL), urea (mg/dL), uric acid (mg/dL), triglycerides (mg/dL), total cholesterol (mg/dL), total proteins (g/dL), transferrin (mg/dL) and albumin (mg/dL).
Time frame: 2 months
Hormonal parameters
Hormonal parameters were performed after 12 hours of fasting first thing in the morning, by specialists puncturing the cubital vena cava (Venoject®) and determined by colorimetric enzymoimmunoassay techniques (ECLIA, Elecsys 2010 and Modular Analytics E170, Roche Diagnostics, Mannheim, Germany. The following measurements were taken: leptin (ng/mL), PTH (pg/mL) and Osteocalcin (pg/mL).
Time frame: 2 months