The Circulating Concentration and 24-h Urine Excretion of Magnesium Dose- and Time-Dependently Respond to Oral Magnesium Supplementation in a Meta-Analysis of Randomized Controlled Trials.
J Nutr
; 146(3): 595-602, 2016 Mar.
Article
em En
| MEDLINE
| ID: mdl-26865651
ABSTRACT
BACKGROUND:
Accurate determination of Mg status is important for improving nutritional assessment and clinical risk stratification.OBJECTIVE:
We aimed to quantify the overall responsiveness of Mg biomarkers to oral Mg supplementation among adults without severe diseases and their dose- and time responses using available data from randomized controlled trials (RCTs).METHODS:
We identified 48 Mg supplementation trials (n = 2131) through searches of MEDLINE and the Cochrane Library up to November 2014. Random-effects meta-analysis was used to estimate weighted mean differences of biomarker concentrations between intervention and placebo groups. Restricted cubic splines were used to determine the dose- and time responses of Mg biomarkers to supplementation.RESULTS:
Among the 35 biomarkers assessed, serum, plasma, and urine Mg were most commonly measured. Elemental Mg supplementation doses ranged from 197 to 994 mg/d. Trials ranged from 3 wk to 5 y (median 12 wk). Mg supplementation significantly elevated circulating Mg by 0.04 mmol/L (95% CI 0.02, 0.06) and 24-h urine Mg excretion by 1.52 mmol/24 h (95% CI 1.20, 1.83) as compared to placebo. Circulating Mg concentrations and 24-h urine Mg excretion responded to Mg supplementation in a dose- and time-dependent manner, gradually reaching a steady state at doses of 300 mg/d and 400 mg/d, or after ~20 wk and 40 wk, respectively (all P-nonlinearity ≤ 0.001). The higher the circulating Mg concentration at baseline, the lower the responsiveness of circulating Mg to supplementation, and the higher the urinary excretion (all P-linearity < 0.05). In addition, RBC Mg, fecal Mg, and urine calcium were significantly more elevated by Mg supplementation than by placebo (all P-values < 0.05), but there is insufficient evidence to determine their responses to increasing Mg doses.CONCLUSIONS:
This meta-analysis of RCTs demonstrated significant dose- and time responses of circulating Mg concentration and 24-h urine Mg excretion to oral Mg supplementation.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Suplementos Nutricionais
/
Magnésio
Tipo de estudo:
Clinical_trials
/
Prognostic_studies
/
Systematic_reviews
Limite:
Humans
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article