Association between magnesium intake and the risk of anemia among adults in the United States

Background

Magnesium deficiency is related to an increased risk of anemia, but epidemiological evidence supporting this association remains scarce. The purpose of the present survey was to evaluate the relationship between dietary magnesium intake and the risk of anemia.

Methods

In total, 13,423 participants aged 20-80 years were enrolled using data from the National Health and Nutrition Examination Survey 2011-2016. Magnesium consumption was evaluated using 24 h dietary recalls. Multivariable generalized linear models were developed to demonstrate the association between dietary magnesium intake and the prevalence of anemia.

Results

An inverse association between dietary magnesium intake and the risk of anemia was detected based on a full adjustment model. We evaluated magnesium intake as a categorical variable (five quartiles). Compared with the lowest value, the highest multivariate adjusted odds ratio (95% confidence interval) for anemia was 0.64 (0.46-0.89). Stratified analyses revealed a reverse relationship between magnesium intake and anemia in women. However, no significant association was observed in men (p _{for trend} = 0.376). A similar reverse association was found among the older group (aged ≥60 years).

Conclusion

Magnesium deficiency is closely related to a higher rate of anemia occurrence, especially among women and older Americans. Further larger-scale prospective studies are required to confirm these conclusions.

Association between Elevated Magnesium Intake and Reduced Risk of Recurrent Falls and Frailty in Osteoarthritis: Data from the Osteoarthritis Initiative

OBJECTIVES

The objective of this 8-year follow-up study was to investigate the relationship between magnesium intake and frailty, as well as recurrent falls, in individuals diagnosed with Osteoarthritis (OA) or those at a heightened risk for developing the condition.

METHODS

This study utilized data from the Osteoarthritis Initiative (OAI) database and conducted a prospective cohort study with a 8-year follow-up period. Total magnesium intake from both food sources and supplements was assessed using a food frequency questionnaire (FFQ), while frailty and recurrent falls were evaluated through established criteria and self-report, respectively. To account for potential confounding factors, various covariates were considered, and statistical analyses, including generalized additive mixed models (GAMMs), were employed to examine the associations.

RESULTS

Among the 4,667 participants with OA, those with lower total magnesium intake were characterized by younger age, a higher proportion of African American individuals, higher body mass index (BMI), and lower dietary fiber intake (P<0.001). Notably, this group exhibited higher odds of experiencing recurrent falls and frailty (P = 0.034 and 0.006, respectively). Controlling for various factors, the GAMMs consistently revealed negative correlations between magnesium intake and the likelihood of frailty and recurrent falls, with each 1 mg/1000 kcal increase in magnesium intake associated with a 0.5% reduced frailty risk (p < 0.001) and a 0.2% decreased risk of recurrent falls (p = 0.001). Subgroup analyses suggested that increased total magnesium intake from both food sources and supplements may exert a more pronounced preventive effect on recurrent falls and frailty in men, older adults, individuals with normal BMI, and those with higher dietary fiber intake.

CONCLUSIONS

Elevated total magnesium intake from both food sources and supplements was found to be associated with a decreased risk of recurrent falls and frailty in individuals diagnosed with OA or those at risk of developing the condition. These findings imply that increased total magnesium intake might be beneficial in managing the risk of these outcomes, particularly within specific subgroups, including men, older adults, those with a normal BMI, and those with higher dietary fiber intake.

Associations between dietary magnesium intake and handgrip strength were modified by serum vitamin D level among the US elderly

Objective

The present study aimed to evaluate the associations between dietary magnesium intake and handgrip strength, and whether these associations were affected by serum vitamin D status.

Methods

A total of 2,127 participants aged 60 and above from the National Health and Nutrition Examination Survey (NHANES) of the 2011-2014 cycles were included in the analyses. Magnesium intake was obtained by 24-h dietary recalls and 30-day dietary supplement. Participants in the lowest sex-specific tertile of magnesium intake were defined as having low magnesium intake. Serum 25-hydroxyvitamin D [25(OH)D)] concentrations were examined by using ultra-high performance liquid chromatography tandem mass spectrometry and categorized into three levels: deficient, suboptimal, and sufficient. Handgrip strength was determined by using a dynamometer. Multivariable linear regression models were used to investigate the associations between dietary magnesium intake and handgrip strength.

Results

Low magnesium intake was not associated with handgrip strength, but interactions between low magnesium intake and serum 25(OH)D level existed on handgrip strength. The stratified analyses found that only in participants with deficient serum 25(OH)D, low magnesium intake was associated with reduced handgrip strength. The combined analyses shown that participants with both low magnesium intake and deficient serum 25(OH)D had highest decrease of handgrip strength.

Conclusion

Findings suggested that low magnesium intake was associated with reduced handgrip strength only in participants with deficient serum 25(OH)D. Increased magnesium intake was recommended for participants with deficient serum 25(OH)D in maintaining muscle strength.

Association between magnesium intake and cognition in US older adults: National Health and Nutrition Examination Survey (NHANES) 2011 to 2014

INTRODUCTION

Identifying nutrition- and modifiable lifestyle-based risk factors for cognitive decline and dementia may contribute future primary prevention strategies. This study aimed to evaluate the associations between magnesium intake and cognition in older adults in the United States.

METHODS

Based on the National Health and Nutrition Survey (NHANES) between 2011 and 2014, the study included 2508 participants aged 60 years and older. Linear regression models were used to examine the association of total magnesium intake with cognition.

RESULTS

After adjusted demographic and other confounding factors, intakes of energy and total calcium, and serum vitamin D level, higher intake of total magnesium was independently associated with 0.15 higher global cognitive z-score (95% confidence interval, 0.02 to 0.28 for highest vs. lowest quartile, P trend = .037). The positive association of total magnesium intake with global cognition was primarily presented among women, non-Hispanic Whites, and those with sufficient serum vitamin D levels (≥50 nmol/L), although interactions were not significant. There were no clear linear associations for global cognition with serum vitamin D level.

DISCUSSIONS

Our findings suggest that high magnesium intake alone may improve cognition in older adults, particularly among non-Hispanic Whites and subjects with sufficient levels of serum vitamin D. Further studies are needed to confirm the findings.

Magnesium dietary intake and physical activity in Type 2 diabetes by gender in White, African-American and Mexican American: NHANES 2011-2014

Aims

To analyse the causal relationships of nutrition intake and physical activity on haemoglobin A1c (HbA1C) in patients diagnosed with type 2 diabetes mellitus (T2DM) stratified by gender and ethnicity.

Materials and Methods

An historical cohort of patients with diagnosed T2DM (n = 2831) was extracted from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 public database, including but not limited to, measurements of physical activity, nutrition, body mass index (BMI) and HbA1c. Multivariate analyses and path analyses were employed to estimate the regression coefficients and path coefficients (ρ) of causal path models of physical activity and nutrition intake on HbA1c stratified by gender and three ethnicity groups (ie non-Hispanic white, non-Hispanic black and Mexican American).

Results

A significant causal path from increased physical activity to increased magnesium (Mg) intake to decreased HbA1c was found. In addition, increased physical activity significantly decreased BMI, which further decreased HbA1c. These results varied by gender and ethnicity but were directionally consistent. Physical activity decreased HbA1c through BMI for males and through Mg intake for females. Mexican American decreased HbA1c through Mg intake, while non-Hispanic black had an increased HbA1c due to its ethnicity and through increased BMI.

Conclusions

The beneficial effects of physical activity on decreased HbA1c were mediated through the increased Mg intake and decreased BMI. This aligned with recent investigations of the inverse causal association of Mg intake with insulin resistance and with decreased inflammation.

Association of magnesium intake with type 2 diabetes and total stroke: an updated systematic review and meta-analysis

OBJECTIVE

The detailed associations between type 2 diabetes (T2D) and total stroke and magnesium intake as well as the dose-response trend should be updated in a timely manner.

DESIGN

Systematic review and meta-analyses.

DATA SOURCES

PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov were rigorously searched from inception to 15 March 2019.

ELIGIBILITY CRITERIA

Prospective cohort studies investigating these two diseases were included.

DATA SYNTHESIS

Relative risk (RR) and 95% CI in random effects models as well as absolute risk (AR) were pooled to calculate the risk of T2D and stroke. Methodological quality was assessed by the Newcastle-Ottawa Scale.

RESULTS

Forty-one studies involving 53 cohorts were included. The magnitude of the risk was significantly reduced by 22% for T2D (RR 0.78 (95% CI 0.75 to 0.81); p<0.001; AR reduction 0.120%), 11% for total stroke (RR 0.89 (95% CI 0.83 to 0.94); p<0.001; AR reduction 0.281%) and 12% for ischaemic stroke (RR 0.88 (95% CI 0.81 to 0.95); p=0.001; AR reduction 0.246%) when comparing the highest magnesium intake to the lowest. The inverse association still existed when studies on T2D were adjusted for cereal fibre (RR 0.79; p<0.001) and those on total stroke were adjusted for calcium (RR 0.89; p=0.040). Subgroup analyses suggested that the risk for total and ischaemic stroke was significantly decreased in females, participants with ≥25 mg/m² body mass index and those with ≥12-year follow-up; the reduced risk in Asians was not as notable as that in North American and European populations.

CONCLUSIONS

Magnesium intake has significantly inverse associations with T2D and total stroke in a dose-dependent manner. Feasible magnesium-rich dietary patterns may be highly beneficial for specific populations and could be highlighted in the primary T2D and total stroke prevention strategies disseminated to the public.

PROSPERO REGISTRATION NUMBER

CRD42018092690.

Trends in Magnesium Intake among Hispanic Adults, the National Health and Nutrition Examination Survey (NHANES) 1999-2014

This study aimed at examining trends in magnesium intake among U.S. Hispanic adults stratified by gender, Hispanic origins, age, and poverty income ratio (PIR) level. Data on 9304 Hispanic adults aged ≥20 years from eight National Health and Nutrition Examination Survey (NHANES) cycles (1999-2014) were included in this study. For each cycle, survey-weighted mean dietary and total magnesium intakes were estimated. The prevalence of dietary and total magnesium intake below the Recommended Dietary Allowance (RDA) was further estimated stratified by gender and age groups. Linear regression was used to test trend. Over the survey cycles, both dietary and total magnesium intakes were significantly increased among Hispanic adults. In the study period, magnesium intake tended to be lower in females, adults in other Hispanic-origin group, those aged ≥65 years old, and those with a PIR <1.0. The prevalence of magnesium intake inadequacy decreased among Hispanic adults; however, more than 70% of Hispanic males and females continued to have magnesium intake below the RDA in 2013-2014. From 1999/2000 to 2013/2014, despite several improvements in magnesium intake having been identified, additional findings showed insufficient intake in Hispanic males and females, suggesting the need to improve magnesium intake through diet and dietary supplementation for U.S. Hispanics.

The ratio potassium-to-magnesium intake and high blood pressure

BACKGROUND

To analyse whether the weight ratio of potassium-to-magnesium intake is associated with incident high blood pressure, in otherwise healthy individuals.

MATERIALS AND METHODS

A total of 529 healthy individuals were enrolled in a cross-sectional study and allocated into following groups: group 1) potassium and magnesium intake within Recommended Dietary Allowance; group 2) magnesium intake as recommended and potassium intake below of recommended dietary allowance; group 3) potassium intake as recommended and magnesium intake below of recommended dietary allowance; and group 4) magnesium and potassium intake below recommended dietary allowance. Groups in study were matched by sodium and calcium intake. A "24 hours recall" questionnaire was used to register all intakes of food and drinks for two consecutive days. Multiple logistic regression analysis adjusted by sex, waist circumference, and triglycerides levels was used to compute the odds ratio between intakes of magnesium and potassium with the high blood pressure.

RESULTS

High blood pressure was identified in 155 (29.3%) individuals. There were no statistical significant differences by obesity and overweight between the groups. As compared with individuals in the group 1, the potassium-to-magnesium ratio (odds ratio 0.88; 95%CI 0.85-0.93) but not the isolated magnesium and potassium intake per se, was inversely associated to high blood pressure in the subjects of group 4; individuals in the groups 2 and 3 showed no association.

CONCLUSIONS

Our results suggest that, in healthy individuals with magnesium and potassium intake below recommended dietary allowance, the high potassium-to-magnesium ratio is inversely associated with incident high blood pressure.

Longitudinal Study of the Role of Epidermal Growth Factor on the Fractional Excretion of Magnesium in Children: Effect of Calcineurin Inhibitors

BACKGROUND

It was shown in animal models and adults that the epidermal growth factor (EGF) is involved in the pathophysiology of calcineurin inhibitor (CNI) induced renal magnesium loss. In children, however, the exact mechanism remains unclear, which was set as the purpose of the present study.

METHODS

Children with nephrotic syndrome and renal transplant children treated with CNI (n = 50) and non-CNI treated children (n = 46) were included in this study. Urine and serum samples were collected at three time points to determine magnesium, creatinine, and EGF. The magnesium intake was calculated from a food frequency questionnaire.

RESULTS

Serum Mg²⁺ and urinary EGF/creatinine were significantly lower in the CNI treated children, with significantly more CNI-treated children developing hypomagnesaemia. In the latter patients, the fractional excretion of magnesium (FE Mg²⁺) was significantly higher. Urinary EGF, age, renal function, and serum magnesium were independent predictors of the FE Mg²⁺. Only 29% of the children reached the recommended daily intake of magnesium. The magnesium intake did not differ between hypomagnesemic and normomagnesemic patients and was not a predictor of the FE Mg²⁺.

CONCLUSIONS

In CNI-treated children who developed hypomagnesemia, the FE Mg²⁺ was increased. The urinary EGF concentration, age, and renal function are independent predictors of the FE Mg²⁺.

Magnesium intake and incidence of pancreatic cancer: the VITamins and Lifestyle study

BACKGROUND

Studies document that magnesium is inversely associated with the risk of diabetes, which is a risk factor of pancreatic cancer. However, studies on the direct association of magnesium with pancreatic cancer are few and findings are inconclusive. In this study, we aimed to investigate the longitudinal association between magnesium intake and pancreatic cancer incidence in a large prospective cohort study.

METHOD

A cohort of 66,806 men and women aged 50-76 years at baseline who participated in the VITamins And Lifestyle (VITAL) study was followed from 2000 to 2008. Multivariable-adjusted Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of pancreatic cancer incidence by magnesium intake categories.

RESULT

During an average of 6.8-year follow-up, 151 participants developed pancreatic cancer. Compared with those who met the recommended dietary allowance (RDA) for magnesium intake, the multivariable-adjusted HRs (95% CIs) for pancreatic cancer were 1.42 (0.91, 2.21) for those with magnesium intake in the range of 75-99% RDA and 1.76 (1.04, 2.96) for those with magnesium intake <75% RDA. Every 100 mg per day decrement in magnesium intake was associated with a 24% increase in the incidence of pancreatic cancer (HR: 1.24; 95% CI: 1.02, 1.50; P(trend)=0.03). The observed inverse associations appeared not to be appreciably modified by age, gender, body mass index, and non-steroidal anti-inflammatory drug use but appeared to be limited to those taking magnesium supplementation (from multivitamins or individual supplement).

CONCLUSIONS

Findings from this prospective cohort study indicate that magnesium intake may be beneficial in terms of primary prevention of pancreatic cancer.

Genetic variations in magnesium-related ion channels may affect diabetes risk among African American and Hispanic American women

BACKGROUND

Prospective studies consistently link low magnesium intake to higher type 2 diabetes (T2D) risk.

OBJECTIVE

We examined the association of common genetic variants [single nucleotide polymorphisms (SNPs)] in genes related to magnesium homeostasis with T2D risk and potential interactions with magnesium intake.

METHODS

Using the Women's Health Initiative-SNP Health Association Resource (WHI-SHARe) study, we identified 17 magnesium-related ion channel genes (583 SNPs) and examined their associations with T2D risk in 7287 African-American (AA; n = 1949 T2D cases) and 3285 Hispanic-American (HA; n = 611 T2D cases) postmenopausal women. We performed both single- and multiple-locus haplotype analyses.

RESULTS

Among AA women, carriers of each additional copy of SNP rs6584273 in cyclin mediator 1 (CNNM1) had 16% lower T2D risk [OR: 0.84; false discovery rate (FDR)-adjusted P = 0.02]. Among HA women, several variants were significantly associated with T2D risk, including rs10861279 in solute carrier family 41 (anion exchanger), member 2 (SLC41A2) (OR: 0.54; FDR-adjusted P = 0.04), rs7174119 in nonimprinted in Prader-Willi/Angelman syndrome 1 (NIPA1) (OR: 1.27; FDR-adjusted P = 0.04), and 2 SNPs in mitochondrial RNA splicing 2 (MRS2) (rs7738943: OR = 1.55, FDR-adjusted P = 0.01; rs1056285: OR = 1.48, FDR-adjusted P = 0.02). Even with the most conservative Bonferroni adjustment, two 2-SNP-haplotypes in SLC41A2 and MRS2 region were significantly associated with T2D risk (rs12582312-rs10861279: P = 0.0006; rs1056285-rs7738943: P = 0.002). Among women with magnesium intake in the lowest 30% (AA: ≤0.164 g/d; HA: ≤0.185 g/d), 4 SNP signals were strengthened [rs11590362 in claudin 19 (CLDN19), rs823154 in SLC41A1, rs5929706 and rs5930817 in membra; HA: ≥0.313 g/d), rs6584273 in CNNM1 (OR: 0.71; FDR-adjusted P = 0.04) and rs1800467 in potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) (OR: 2.50; FDR-adjusted P = 0.01) were significantly associated with T2D risk.

CONCLUSIONS

Our findings suggest important associations between genetic variations in magnesium-related ion channel genes and T2D risk in AA and HA women that vary by amount of magnesium intake.

Magnesium, vitamin D status and mortality: results from US National Health and Nutrition Examination Survey (NHANES) 2001 to 2006 and NHANES III

BACKGROUND

Magnesium plays an essential role in the synthesis and metabolism of vitamin D and magnesium supplementation substantially reversed the resistance to vitamin D treatment in patients with magnesium-dependent vitamin-D-resistant rickets. We hypothesized that dietary magnesium alone, particularly its interaction with vitamin D intake, contributes to serum 25-hydroxyvitamin D (25(OH)D) levels, and the associations between serum 25(OH)D and risk of mortality may be modified by magnesium intake level.

METHODS

We tested these novel hypotheses utilizing data from the National Health and Nutrition Examination Survey (NHANES) 2001 to 2006, a population-based cross-sectional study, and the NHANES III cohort, a population-based cohort study. Serum 25(OH)D was used to define vitamin D status. Mortality outcomes in the NHANES III cohort were determined by using probabilistic linkage with the National Death Index (NDI).

RESULTS

High intake of total, dietary or supplemental magnesium was independently associated with significantly reduced risks of vitamin D deficiency and insufficiency respectively. Intake of magnesium significantly interacted with intake of vitamin D in relation to risk of both vitamin D deficiency and insufficiency. Additionally, the inverse association between total magnesium intake and vitamin D insufficiency primarily appeared among populations at high risk of vitamin D insufficiency. Furthermore, the associations of serum 25(OH)D with mortality, particularly due to cardiovascular disease (CVD) and colorectal cancer, were modified by magnesium intake, and the inverse associations were primarily present among those with magnesium intake above the median.

CONCLUSIONS

Our preliminary findings indicate it is possible that magnesium intake alone or its interaction with vitamin D intake may contribute to vitamin D status. The associations between serum 25(OH)D and risk of mortality may be modified by the intake level of magnesium. Future studies, including cohort studies and clinical trials, are necessary to confirm the findings.