Dietary magnesium intake in relation to plasma insulin levels and risk of type 2 diabetes in women

Nigella sativa L. and its bioactive and nutraceutical components in the management of diabetic peripheral neuropathy

Diabetes-induced hyperglycemia leads to excessive production of oxygen free radicals, inflammatory cytokines, and oxidative stress, which initiates diabetic peripheral neuropathy (DPN). Currently, this condition affects 20% of adults with diabetes. Despite significant advances in the treatment of diabetes, the incidence of its complications, including DPN, is still high. Thus, there is a growing research interest in developing more effective and treatment approaches with less side effects for diabetes and its complications. Nigella sativa L. (NS) has received much research attention as an antioxidant, anti-yperglycemic factor, and anti-inflammatory agent. This natural compound demonstrates its antidiabetic neuropathy effect through various pathways, including the reduction of lipid peroxidation, the enhancement of catalase and superoxide dismutase enzyme activity, and the decrease in inflammatory cytokine levels. The present review focuses on the bioactive and nutraceutical components of black cumin (Nigella sativa L.) and their effects on DPN. In addition, we have also summarized the findings obtained from several experimental and clinical studies regarding the antidiabetic neuropathy effect of NS in animal models and human subjects.

Coffee consumption and cardiometabolic health: a comprehensive review of the evidence

This review provides a comprehensive synthesis of longitudinal observational and interventional studies on the cardiometabolic effects of coffee consumption. It explores biological mechanisms, and clinical and policy implications, and highlights gaps in the evidence while suggesting future research directions. It also reviews evidence on the causal relationships between coffee consumption and cardiometabolic outcomes from Mendelian randomization (MR) studies. Findings indicate that while coffee may cause short-term increases in blood pressure, it does not contribute to long-term hypertension risk. There is limited evidence indicating that coffee intake might reduce the risk of metabolic syndrome and non-alcoholic fatty liver disease. Furthermore, coffee consumption is consistently linked with reduced risks of type 2 diabetes (T2D) and chronic kidney disease (CKD), showing dose-response relationships. The relationship between coffee and cardiovascular disease is complex, showing potential stroke prevention benefits but ambiguous effects on coronary heart disease. Moderate coffee consumption, typically ranging from 1 to 5 cups per day, is linked to a reduced risk of heart failure, while its impact on atrial fibrillation remains inconclusive. Furthermore, coffee consumption is associated with a lower risk of all-cause mortality, following a U-shaped pattern, with the largest risk reduction observed at moderate consumption levels. Except for T2D and CKD, MR studies do not robustly support a causal link between coffee consumption and adverse cardiometabolic outcomes. The potential beneficial effects of coffee on cardiometabolic health are consistent across age, sex, geographical regions, and coffee subtypes and are multi-dimensional, involving antioxidative, anti-inflammatory, lipid-modulating, insulin-sensitizing, and thermogenic effects. Based on its beneficial effects on cardiometabolic health and fundamental biological processes involved in aging, moderate coffee consumption has the potential to contribute to extending the healthspan and increasing longevity. The findings underscore the need for future research to understand the underlying mechanisms and refine health recommendations regarding coffee consumption.

Global prevalence of hypomagnesemia in type 2 diabetes mellitus - a comprehensive systematic review and meta-analysis of observational studies

PURPOSE

Hypomagnesemia, characterized by low magnesium levels, has been implicated in the pathophysiology of Type 2 Diabetes Mellitus (T2DM). This meta-analysis aims to provide a comprehensive assessment of hypomagnesemia prevalence in individuals with T2DM as well as its potential implications for diabetes management and complications.

METHODS

We conducted a comprehensive systematic review and meta-analysis using databases like PubMed, Google Scholar, Science Direct, and Research Gate to identify relevant studies between January 2008 and August 2023. We focused on observational studies related to serum magnesium levels and Type 2 Diabetes in individuals aged 19 and older. Newcastle Ottawa tool was used for quality assessment. A random effect meta-analysis was performed to calculate the prevalence of hypomagnesemia in T2DM.

RESULTS

We identified a total of 671 studies, and after screening 383 abstracts and full texts by two independent reviewers, we identified 19 eligible studies encompassing 4192 patients diagnosed with T2DM. The mean age was 55.4 (SD, 4.39) years with a mean HbA1C level of 8.01. The pooled prevalence of hypomagnesemia in T2DM was 32% (95% CI: 22-36%) out of 4192 cases. On subgroup analysis, the prevalence of hypomagnesemia in male and female were 19.8% and 20.1%, respectively. Geographically, Asia had the highest prevalence of hypomagnesemia with 31.9% (95% CI: 24-41.1%).

CONCLUSION

This meta-analysis highlights a significant prevalence of hypomagnesemia in individuals with T2DM, emphasizing the need for further investigation due to the intricate nature of the association between serum magnesium levels and T2DM.

Prevalence of Dysmagnesemia among Patients with Diabetes Mellitus and the Associated Health Outcomes: A Cross-Sectional Study

Introduction: Magnesium is a vital intracellular cation crucial for over 320 enzymatic reactions related to energy metabolism, musculoskeletal function, and nucleic acid synthesis and plays a pivotal role in human physiology. This study aimed to explore the prevalence of dysmagnesemia in patients with diabetes mellitus and evaluate its correlations with glycemic control, medication use, and diabetic complications. Methods: A cross-sectional study was conducted at Sultan Qaboos University Hospital, including 316 patients aged 18 years or older with diabetes mellitus. Data included demographics, medical history, medications, and biochemical parameters. Serum total magnesium concentrations were measured, and dysmagnesemia was defined as magnesium ≤ 0.69 mmol/L for hypomagnesemia and ≥1.01 mmol/L for hypermagnesemia. Results: The prevalence of hypomagnesemia in patients with diabetes was 17.1% (95% CI: 13.3-21.7%), and hypermagnesemia was 4.1% (95% CI: 2.4-7.0%). Females were significantly overrepresented in the hypomagnesemia group, while the hypermagnesemia group showed a higher prevalence of hypertension, retinopathy, an increased albumin/creatinine ratio, chronic kidney disease (CKD), elevated creatinine levels, and a lower adjusted calcium concentration. The multinominal logistic regression exhibited that the female sex and higher serum-adjusted calcium were independent risk factors of hypomagnesemia. In contrast, the presence of hypertension, higher levels of albumin/creatinine ratio, and stage 5 CKD were independent risk factors of hypermagnesemia. Conclusions: Hypomagnesemia was common among patients with diabetes mellitus; however, hypermagnesemia was associated with microvascular complications.

Association between dietary antioxidants intake and the risk of type 2 diabetes mellitus in a prospective cohort study: Tehran Lipid and Glucose Study

The present prospective cohort study aimed to determine whether dietary antioxidants were associated with incident type 2 diabetes mellitus (T2DM). Another objective was to find out whether such associations could be modified by the BMI status. A total of 2188 Tehranian adults aged 21-84 years, free of T2DM with the validated FFQ, was entered in the study. Multivariable Cox proportional hazards models adjusting for confounders were used to assess the association between dietary antioxidants and incident T2DM in total population, as well as in subjects with various BMI statuses. During 8·9 (8·1-9·6) years of follow-up, dietary vitamin E significantly decreased the incident T2DM, after adjustment for confounders. However, other dietary antioxidants were not shown to be significantly associated with incident T2DM. The interaction between dietary vitamin E, Mg and BMI status was found to influence the risk of T2DM (Pfor interaction < 0·05). After stratification of subjects based on BMI status, it was found that vitamin E and Mg decreased the risk of T2DM only among normal-weight individual. Also, an inverse association was found among dietary vitamin C, dietary Zn and the risk of T2DM in individuals with normal weight but not in overweight and obese individuals; however, the interaction test tended to be significant for these dietary variables. Dietary antioxidants including vitamin E, vitamin C, Zn and Mg when accompanied by healthy weight, may bring benefits to the prevention of T2DM.

Study on the Dose-Response Relationship between Magnesium and Type 2 Diabetes of Childbearing Women in the China Adult Chronic Disease and Nutrition Surveillance 2015

Background: Magnesium (Mg) is an essential element and participates in many metabolic pathways. Many studies have found a certain negative correlation between magnesium and blood glucose parameters, but the dose-response relationship between them is still a relatively narrow research field. We aim to explore the dose-response relationship between plasma and dietary Mg and type 2 diabetes (T2DM) among childbearing women in a nationally representative sample. And we will also initially explore the threshold of dietary and plasma magnesium in the prevention of T2DM and their consistency. Methods: A total of 2912 18-44 year-old childbearing women were recruited from the China Adult Chronic Disease and Nutrition Surveillance (2015). Multivariate logistic regression was used to explore the dose-response relationship between plasma and dietary Mg and glucose parameters. The threshold effect between Mg and T2DM was explored by a restricted cubic spline regression. Results: It was found that when plasma Mg was increased by 0.041 mmol/L, the risk of T2DM, impaired fasting glucose (IFG), and HbA1c-hyperglycemia was reduced by 18%, 19%, and 18%, respectively. The possible threshold value for plasma Mg to prevent the risk of T2DM was 0.87 mmol/L. Through the quality control of the sample dietary survey data, 2469 cases were finally included for dietary analysis. And the possible threshold value for dietary Mg to prevent the risk of T2DM was 408 mg/d. Taking the recommended dietary Mg intake of 330 mg/d as the reference group, when the Mg intake reached 408 mg/d, the risk of T2DM was significantly reduced. And the average plasma Mg level of the people whose dietary intake reached 408 mg/d was 0.87 mmol/L. Conclusions: These results indicate that dietary Mg and plasma Mg have good consistency on the threshold effect of glucose parameters in women of childbearing age.

Association between dietary magnesium intake and gallstones: the mediating role of atherogenic index of plasma

BACKGROUND

Dyslipidemia and abnormalities in cholesterol metabolism are commonly observed in individuals with gallstone disease. Previous research has demonstrated that dietary magnesium can influence lipid metabolism. The atherogenic index of plasma (AIP) has emerged as a novel lipid marker. This study aimed to examine the possible correlation between dietary magnesium intake and gallstones and the potential mediating role of AIP in US adults.

METHODS

A total of 4,841 adults were included in this study from the National Health and Nutrition Examination Survey (NHANES) conducted from 2017 to 2020. A variety of statistical techniques such as logistic regression, subgroup analysis, smoothed curve fitting, and causal mediation analysis were utilized to analyze the information collected from the participants.

RESULTS

In the fully adjusted model, a statistically noteworthy inverse relationship was observed between dietary magnesium intake and the presence of gallstones, as indicated by an odds ratio (OR) of 0.58 and a 95% confidence interval (CI) of (0.42, 0.81). Causal intermediary analysis revealed that the association between magnesium intake and gallstones was partially mediated by AIP, with a mediation ratio of 3.2%.

CONCLUSION

According to this study, dietary magnesium intake had a significant linear negative association with the prevalence of gallstones, in which AIP played a mediating role. This discovery offers novel perspectives on the prevention and management of gallstones.

Magnesium and the Hallmarks of Aging

Magnesium is an essential ion in the human body that regulates numerous physiological and pathological processes. Magnesium deficiency is very common in old age. Age-related chronic diseases and the aging process itself are frequently associated with low-grade chronic inflammation, called 'inflammaging'. Because chronic magnesium insufficiency has been linked to excessive generation of inflammatory markers and free radicals, inducing a chronic inflammatory state, we formerly hypothesized that magnesium inadequacy may be considered among the intermediaries helping us explain the link between inflammaging and aging-associated diseases. We show in this review evidence of the relationship of magnesium with all the hallmarks of aging (genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, disabled autophagy, dysbiosis, and chronic inflammation), which may positively affect the human healthspan. It is feasible to hypothesize that maintaining an optimal balance of magnesium during one's life course may turn out to be a safe and economical strategy contributing to the promotion of healthy aging. Future well-designed studies are necessary to further explore this hypothesis.

Assessment of dietary magnesium intake in the Eastern Province of Saudi Arabia

Magnesium is an essential element and the most abundant intracellular cation after potassium. This cross-sectional study assessed the average dietary magnesium intake among residents of the Eastern Province of Saudi Arabia. Data was collected using a self-reported validated electronic questionnaire between April 2022 and July 2023. The first part of the survey included demographic data, and the second section comprised 33 items, including a semi-quantitative tool specifically designed to evaluate magnesium intake over the last three months. We included 1065 participants, out of whom 61.1% were women. The predominant age group was 19 - 26 years (56.9%), and most participants (83.3%) reported no comorbidities. The majority (48.5%) had normal weight, 246 (23%) were overweight, and 193 (18.1%) were obese. Most participants had low dietary magnesium intake, ranging from one to five times monthly. There was a positive correlation between age and dietary magnesium consumption. The study highlights a concerning trend of low magnesium intake, representing a risk for various chronic diseases. This trend could be linked to increased consumption of typical diets low in magnesium, such as those high in refined sugars, flour, and processed foods, prevalent among the younger Saudi population.

Comparison of Magnesium Status Using 24-h Urine Magnesium Content and Magnesium Fraction Excretion in PCOS with Non-PCOS Control Women: a Cross-sectional Study

Magnesium (Mg) is the second most frequent intracellular cation, having an important role in normal enzyme function and insulin secretion. Polycystic ovarian syndrome (PCOS) is the most prevalent endocrinopathy in women of reproductive age and often associated with insulin resistance. Two systematic reviews and meta-analyses have been conducted to compare mean serum Mg levels between PCOS and control groups. Both studies detected unexplained heterogeneity among input studies and the two conclusions contradict each other, while approximately 1% of total body Mg is present in extracellular fluid (ECF) and serum Mg level does not represent Mg status well. For the first time, we investigated magnesium renal fraction excretion (FEMg) and compared mean values between PCOS and non-PCOS control women. This study is a cross-sectional analysis conducted at an academic medical center. Forty-four women were included in the PCOS group based on the Rotterdam criteria and 50 non-PCOS women were included in the control group. Statistical analysis of the relationship between 24-h urinary Mg content and FEMg, and also physical and metabolic variables, was performed. Main outcome measurements are 24-h urinary Mg content and FEMg. Mean values of 24-h urinary Mg content and FEMg did not significantly differ between PCOS and control groups (P = 0.22 and P = 0.24, respectively). Also, serum Mg levels and Ca/Mg ratio were similar between the groups (P = 0.17 and P = 0.26, respectively). Our data suggested Mg status in the PCOS group was similar to the non-PCOS control group and both were not magnesium deficient. For further investigation, we recommend using FEMg for evaluating Mg status rather than serum Mg levels. Considering collection of background diet is helpful and desired for future studies.

Association of Magnesium Depletion Score With Cardiovascular Disease and Its Association With Longitudinal Mortality in Patients With Cardiovascular Disease

Background Dietary magnesium and serum magnesium play an important part in cardiovascular disease (CVD). However, the association between magnesium depletion score (MDS) and CVD development and prognosis remains unclear. This analysis examines the cross-sectional relationship between MDS and CVD, and the longitudinal association between MDS and all-cause and CVD mortality in individuals with CVD. Methods and Results In all, 42 711 individuals were selected from the National Health and Nutrition Examination Survey, including 5015 subjects with CVD. The association between MDS and total and individual CVDs was examined using the survey-weighted multiple logistic regression analysis. Among 5011 patients with CVD, 2285 and 927 participants were recorded with all-cause and CVD deaths, respectively. We applied survey-weighted Cox proportional hazards regression analyses to investigate the impact of MDS on the mortality of individuals with CVD. The CVD group had higher MDS levels than the non-CVD groups. After controlling all confounding factors, individuals with MDS of 2 and ≥3 had higher odds of total CVD and specific CVD than those with MDS of 0. Besides, each 1-unit increase in MDS was strongly related to the risk of total CVD and specific CVD. The relationship between MDS and total CVD was stable and significant in all subgroups. The fully adjusted Cox regression model indicated that high MDS, irrespective of MDS as a categorical or continuous variable, was significantly associated with an elevated risk of all-cause and CVD deaths. Conclusions MDS is a vital risk factor for the prevalence and mortality of individuals with CVD.

The Link between Magnesium Supplements and Statin Medication in Dyslipidemic Patients

Many investigations have discovered a connection between statins and magnesium supplements. On one hand, increasing research suggests that chronic hypomagnesemia may be an important factor in the etiology of some metabolic illnesses, including obesity and overweight, insulin resistance and type 2 diabetes mellitus, hypertension, alterations in lipid metabolism, and low-grade inflammation. Chronic metabolic problems seem to be prevented by a high Mg intake combined with diet and/or supplements. On the other hand, it is known that statins lower the frequency of cardiac events, stroke, and mortality, not by lowering LDL-C, but by the capacity to reduce mevalonate formation. That will enhance endothelial function, inhibit vascular smooth muscle cell proliferation and migration and encourage macrophages to promote plaque stability and regression while reducing inflammation. Taking these factors into consideration, we did an extensive analysis of the relevant literature, comparing the effects of Mg² and statin medications on lipoproteins and, implicitly, on the key enzymes involved in cholesterol metabolism.

Effects of magnesium supplementation on improving hyperglycemia, hypercholesterolemia, and hypertension in type 2 diabetes: A pooled analysis of 24 randomized controlled trials

Background

Previous studies have demonstrated that diabetes is often accompanied with lower magnesium status. However, practical details regarding the influences of magnesium intervention on hyperglycemia, hypercholesterolemia, and hypertension in type 2 diabetes (T2D) need to be further investigated.

Methods

Web of Science, ScienceDirect, and PubMed were searched for relevant literatures published through April 30, 2022, and high-quality data were pooled to evaluate the effects of magnesium supplementation on glycemic, circulating lipids, and blood pressure control in T2D, and to explore the associated practical details.

Results

Pooled analyses of 24 randomized controlled trials with 1,325 T2D individuals revealed that subjects who received magnesium supplementation had statistically significant reductions in fasting plasma glucose, glycated hemoglobin, systolic blood pressure and diastolic blood pressure, with WMD values of -0.20 mM (95% CI: -0.30, -0.09), -0.22% (95% CI: -0.41, -0.03), -7.69 mmHg (95% CI: -11.71, -3.66) and -2.71 mmHg (95% CI: -4.02, -1.40), respectively. Detailed subgroup analyses demonstrated that health status of participants including age, body mass index, country, duration of disease, baseline magnesium level and baseline glycemic control condition as well as magnesium formulation, dosage and duration of intervention influenced the effects of magnesium addition. Dose-effect analysis showed that 279 mg/d for 116 d, 429 mg/d for 88 d and 300 mg/d for 120 d are the average optimal dosages and durations for improving glycemic, circulating lipids, and blood pressure controls, respectively.

Conclusion

Our findings provide clinically relevant information on the adjuvant therapy of magnesium for improving hyperglycemia, hypercholesterolemia, and hypertension in T2D.

The Association of Dietary Magnesium and Prediabetes in Childbearing Chinese Women: Results from China Nutrition and Health Surveillance (2015-2017)

Although several studies have shown the relationship between magnesium and diabetes, there are few studies regarding the association between magnesium status and prediabetes. This study aimed to examine the association between dietary magnesium intake and the risk of prediabetes in childbearing Chinese women (18−44 years). A total of 1981 participants without diabetes were randomly selected from China Nutrition and Health Surveillance (CNHS) in 2015 by considering the regional types and monitoring points, including 1420 normal fasting glucose (NFG) people and 561 prediabetes cases. The Food Frequency Questionnaire (FFQ) and inductively coupled plasma mass spectrometry (ICP-MS) measured dietary and plasma magnesium. The results of this study showed that dietary magnesium intake was inversely associated with fasting plasma glucose. For every 100 mg of magnesium intake, there was a 0.052 mmol/L (95% CI 0.019, 0.085) reduction in fasting plasma glucose (p = 0.002). Compared with the lowest intake quartile (<350.10 mg/day), the third and fourth quartiles (≥405.41 mg/day) reduced the odds risk of prediabetes (OR = 0.63, 95% CI 0.46, 0.88, p = 0.020) by approximately 37%. The dose-response curves for the association between magnesium intake and prediabetes followed an L shape. The odds ratio of prediabetes decreased significantly with increasing dietary Mg intake at less than 410 mg/day, and then the curve leveled off or slightly increased. This study found a negative association between dietary magnesium intake and prediabetes in childbearing Chinese women. The risk of prediabetes was reduced with increasing dietary magnesium intake, and the threshold value was 410 mg/day. This suggests that childbearing women also need to pay attention to their magnesium status.

Magnesium supplementation and insulin resistance in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a multifactorial disease affecting the immune system and many tissues in the body. This study aimed to evaluate the effect of magnesium supplementation on insulin resistance and fasting blood sugar (FBS) of patients with RA. In this prospective uncontrolled before-after study, RA patients referring to Rheumatology clinics of Qom City from January 2020 to January 2021 were evaluated. First, the patients received the routine rheumatoid arthritis treatment including 5 mg Prednisolone and 200mg Hydroxychloroquine daily for 6 months and FBS and insulin levels were measured after. Then, they received the routine arthritis rheumatoid treatment in addition to 300 mg/day oral Magnesium sulfate for 6 months and then, FBS and insulin levels were measured. The Homeostasis Model Assessment of insulin resistance (HOMA-IR) was used for determining insulin resistance. Thirty five patients with RA and the mean age of 49.83±2.58 years were enrolled. Twenty eight cases (80%) were female and 7 cases (20%) were male. The mean HOMA-IR before and after consumption of oral magnesium were 3.04±0.29 and 2.43±0.19, respectively. Statistically significant differences were found between FBS, insulin and HOMA-IR before and after consumption of oral magnesium (p<0.05). Our data suggested that magnesium supplementation reduces FBS, insulin and HOMA-IR in patients with rheumatoid arthritis. Thus, magnesium supplements may be an alternative method for prevention of type 2 diabetes in RA patients.

Long-term association of serum selenium levels and the diabetes risk: Findings from a case-control study nested in the prospective Jinchang Cohort

An increasing body of evidence implicates high levels of selenium intake in the development of diabetes, although prospective studies remain sparse. We conducted a nested case-control study of 622 diabetes incident cases and 622-age, sex, and follow-up time-matched controls in the prospective Jinchang cohort of 48,001 participants with a median of 5.8 years of follow-up. Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure all 622 case-control pairs' baseline serum levels of selenium (Se), which were then categorized into quartiles based on the frequency distribution among the controls. Multivariable adjusted conditional logistic regression and restricted cubic splines (RCS) models were applied to evaluate independent odds ratios (OR) as estimates for relative risks (RR) of diabetes according to quartiles (Q) of selenium levels. Compared to the lowest quartile (Q1 as reference), significantly greater diabetes risks (with 95% confidence interval) were observed in Q3 (OR = 1.62, 1.17-2.35) and Q4 (OR = 1.79, 1.21-2.64). Sub-analyses showed these increased risks of diabetes by serum levels of Se. appeared to differ by sex, age, BMI status, history of hypertension, and dyslipidemia. Further, application of RSC models showed that serum Se levels between 95 and 120 μg/L were significantly and positively associated with diabetes risk whereas no apparent relation exists when Se levels were under 95 μg/L in this cohort population.

Serum magnesium level as a predictor of acute kidney injury in patients with acute pancreatitis

BACKGROUND

Decreased serum magnesium (Mg²⁺) is commonly seen in critically ill patients. Hypomagnesemia is significantly more frequent in patients with severe acute pancreatitis. Acute kidney injury (AKI) in patients with acute pancreatitis (AP) is associated with an extremely high mortality. The association underlying serum Mg²⁺ and AKI in AP has not been elucidated.

AIM

To explore the association between serum Mg²⁺ on admission and AKI in patients with AP.

METHODS

A retrospective observational study was conducted in a cohort of patients (n = 233) with AP without any renal injury before admission to our center from August 2015 to February 2019. Demographic characteristics on admission, severity score, laboratory values and in-hospital mortality were compared between patients with and without AKI.

RESULTS

A total of 233 patients were included for analysis, including 85 with AKI. Compared to patients without AKI, serum Mg²⁺ level was significantly lower in patients with AKI at admission [OR = 6.070, 95%CI: 3.374-10.921, P < 0.001]. Multivariate logistic analysis showed that lower serum Mg²⁺ was an independent risk factor for AKI [OR = 8.47, 95%CI: 3.02-23.72, P < 0.001].

CONCLUSION

Our analysis indicates that serum Mg²⁺ level at admission is independently associated with the development of AKI in patients with AP and may be a potential prognostic factor.

Changes in Dietary Magnesium Intake and Risk of Type 2 Diabetes Mellitus in Middle School Students: Using Data from the HEALTHY Study

BACKGROUND

The HEALTHY Study was a multicomponent school-based intervention, designed to prevent type 2 diabetes mellitus (T2DM) in middle-school students.

OBJECTIVES

We examined whether the difference in dietary magnesium intake, BMI percentile, and plasma glucose and insulin concentrations from 6th to 8th grade were related in the intervention schools and in the control schools that participated in the HEALTHY Study.

METHODS

A total of 2181 ethnically diverse students, from 11.3 to 13.7 y of age, with completed dietary records, BMI percentile, and plasma glucose and insulin concentrations at 6th and 8th grades were included. Dietary magnesium intake was self-reported using the Block Kids FFQ. A hierarchical multiple regression model was used to determine whether the differences in dietary magnesium intake, BMI percentile, and plasma glucose and insulin concentrations from 6th to 8th grades were related, while adjusting for dietary calcium intake and total energy intake.

RESULTS

The difference in dietary magnesium intake was significantly related to changes in BMI percentile from 6th to 8th grade in intervention and in control schools [intervention: β: -0.07; 95% CI: -0.58, -0.02; P = 0.03; R2 (regression coefficient effect size): 0.14; 95% CI for R2: 0.10, 0.17; control: β: -0.08; 95% CI: -0.63, -0.09; P = 0.01; R2: 0.12; 95% CI for R2: 0.08, 0.15]. The difference in dietary magnesium intake was not related to plasma glucose and insulin concentrations in intervention and in control schools.

CONCLUSIONS

We conclude that a multicomponent intervention was associated with reduced risk of T2DM, and that this association may be modulated, in part, by magnesium. The differences in dietary magnesium intake from 6th to 8th grade were negatively related to changes in BMI percentile among middle-school students.

Nutrition in Patients with Type 2 Diabetes: Present Knowledge and Remaining Challenges

Unhealthy behaviours, including diet and physical activity, coupled with genetic predisposition, drive type 2 diabetes (T2D) occurrence and severity; the present review aims to summarise the most recent nutritional approaches in T2D, outlining unmet needs. Guidelines consistently suggest reducing energy intake to counteract the obesity epidemic, frequently resulting in sarcopenic obesity, a condition associated with poorer metabolic control and cardiovascular disease. Various dietary approaches have been proposed with largely similar results, with a preference for the Mediterranean diet and the best practice being the diet that patients feel confident of maintaining in the long term based on individual preferences. Patient adherence is indeed the pivotal factor for weight loss and long-term maintenance, requiring intensive lifestyle intervention. The consumption of nutritional supplements continues to increase even if international societies do not support their systematic use. Inositols and vitamin D supplementation, as well as micronutrients (zinc, chromium, magnesium) and pre/probiotics, result in modest improvement in insulin sensitivity, but their use is not systematically suggested. To reach the desired goals, patients should be actively involved in the collaborative development of a personalised meal plan associated with habitual physical activity, aiming at normal body weight and metabolic control.

Magnesium Deficiency Causes a Reversible, Metabolic, Diastolic Cardiomyopathy

Background Dietary Mg intake is associated with a decreased risk of developing heart failure, whereas low circulating Mg level is associated with increased cardiovascular mortality. We investigated whether Mg deficiency alone could cause cardiomyopathy. Methods and Results C57BL/6J mice were fed with a low Mg (low-Mg, 15-30 mg/kg Mg) or a normal Mg (nl-Mg, 600 mg/kg Mg) diet for 6 weeks. To test reversibility, half of the low-Mg mice were fed then with nl-Mg diet for another 6 weeks. Low-Mg diet significantly decreased mouse serum Mg (0.38±0.03 versus 1.14±0.03 mmol/L for nl-Mg; P<0.0001) with a reciprocal increase in serum Ca, K, and Na. Low-Mg mice exhibited impaired cardiac relaxation (ratio between mitral peak early filling velocity E and longitudinal tissue velocity of the mitral anterior annulus e, 21.1±1.1 versus 15.4±0.4 for nl-Mg; P=0.011). Cellular ATP was decreased significantly in low-Mg hearts. The changes were accompanied by mitochondrial dysfunction with mitochondrial reactive oxygen species overproduction and membrane depolarization. cMyBPC (cardiac myosin-binding protein C) was S-glutathionylated in low-Mg mouse hearts. All these changes were normalized with Mg repletion. In vivo (2-(2,2,6,6-tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl)triphenylphosphonium chloride treatment during low-Mg diet improved cardiac relaxation, increased ATP levels, and reduced S-glutathionylated cMyBPC. Conclusions Mg deficiency caused a reversible diastolic cardiomyopathy associated with mitochondrial dysfunction and oxidative modification of cMyBPC. In deficiency states, Mg supplementation may represent a novel treatment for diastolic heart failure.

Mineral-rich Jeju lava sea water suppresses lipid accumulation in 3T3-L1 adipocytes and ameliorates high-fat diet-induced obesity in C57BL/6 J mice

This research aimed to evaluate the potential inhibitory effect of mineral-rich Jeju lava sea water (JLSW) on lipid accumulation. This study optimized the calcium (Ca): magnesium (Mg) ratio (5:1, 2.5:1, 1:1) of JLSW and evaluated the effect on lipid accumulation in 3T3-L1 cells using Oil Red O staining. JLSW with a high Ca:Mg ratio (5:1) suppressed lipid accumulation in 3T3-L1 adipocytes. Based on these in-vitro results, the effects of JLSW on lipid accumulation were investigated in C57BL/6 J mice fed high-fat diets for 14 weeks. Epididymal adipose tissue weight was significantly decreased in mice that received JLSW with a hardness of 800 or 100 mg/L compared to HFD. Adipocyte size was significantly reduced in mice treated with JLSW with a hardness of 20 mg/L in comparison with HFD. Thus, long-term intake of JLSW may be expected to have anti-obesity effects due to the reduction of lipid accumulation.

Magnesium in Aging, Health and Diseases

Several changes of magnesium (Mg) metabolism have been reported with aging, including diminished Mg intake, impaired intestinal Mg absorption and renal Mg wasting. Mild Mg deficits are generally asymptomatic and clinical signs are usually non-specific or absent. Asthenia, sleep disorders, hyperemotionality, and cognitive disorders are common in the elderly with mild Mg deficit, and may be often confused with age-related symptoms. Chronic Mg deficits increase the production of free radicals which have been implicated in the development of several chronic age-related disorders. Numerous human diseases have been associated with Mg deficits, including cardiovascular diseases, hypertension and stroke, cardio-metabolic syndrome and type 2 diabetes mellitus, airways constrictive syndromes and asthma, depression, stress-related conditions and psychiatric disorders, Alzheimer's disease (AD) and other dementia syndromes, muscular diseases (muscle pain, chronic fatigue, and fibromyalgia), bone fragility, and cancer. Dietary Mg and/or Mg consumed in drinking water (generally more bioavailable than Mg contained in food) or in alternative Mg supplements should be taken into consideration in the correction of Mg deficits. Maintaining an optimal Mg balance all through life may help in the prevention of oxidative stress and chronic conditions associated with aging. This needs to be demonstrated by future studies.

Magnesium and Hypertension in Old Age

Hypertension is a complex condition in which various actors and mechanisms combine, resulting in cardiovascular and cerebrovascular complications that today represent the most frequent causes of mortality, morbidity, disability, and health expenses worldwide. In recent decades, there has been an exceptional number of experimental, epidemiological, and clinical studies confirming a close relationship between magnesium deficit and high blood pressure. Multiple mechanisms may help to explain the bulk of evidence supporting a protective effect of magnesium against hypertension and its complications. Hypertension increases sharply with advancing age, hence older persons are those most affected by its negative consequences. They are also more frequently at risk of magnesium deficiency by multiple mechanisms, which may, at least in part, explain the higher frequency of hypertension and its long-term complications. The evidence for a favorable effect of magnesium on hypertension risk emphasizes the importance of broadly encouraging the intake of foods such as vegetables, nuts, whole cereals and legumes, optimal dietary sources of magnesium, and avoiding processed foods, which are very poor in magnesium and other fundamental nutrients, in order to prevent hypertension. In some cases, when diet is not enough to maintain an adequate magnesium status, magnesium supplementation may be of benefit and has been shown to be well tolerated.

Magnesium, Oxidative Stress, Inflammation, and Cardiovascular Disease

Hypomagnesemia is commonly observed in heart failure, diabetes mellitus, hypertension, and cardiovascular diseases. Low serum magnesium (Mg) is a predictor for cardiovascular and all-cause mortality and treating Mg deficiency may help prevent cardiovascular disease. In this review, we discuss the possible mechanisms by which Mg deficiency plays detrimental roles in cardiovascular diseases and review the results of clinical trials of Mg supplementation for heart failure, arrhythmias and other cardiovascular diseases.

The effects of magnesium supplementation on obesity measures in adults: a systematic review and dose-response meta-analysis of randomized controlled trials

Previous studies reported inconsistent findings regarding the effects of magnesium supplementation on obesity measures. This study was done to quantify the effect of magnesium supplementation on body weight, Body Mass Index (BMI), Waist Circumference (WC), Body Fat (BF) percentage and Waist to Hip Ratio (WHR). Four online databases (Scopus, PubMed, Google Scholar and Cochrane library) were searched until March 2020 using relevant keywords. Random-effects model was used to pool effect sizes; Cochran's Q-test and I2 index assessed heterogeneity. Sensitivity analysis and Egger test were used to check the robustness of findings and the possibility of publication bias, respectively. Thirty-two RCTs including different dosage of magnesium (48-450 mg/d), and duration (6-24 weeks) were entered to this study. Magnesium supplementation resulted in a great reduction in BMI [Weighted Mean Difference (WMD): -0.21 kg/m², 95% CI: -0.41, -0.001, P = 0.048, I² = 89.5%, n = 22], which was mainly driven by the effect among those with magnesium deficiency, insulin resistance related disorders, and obesity at baseline. No significant change was observed in bodyweight, WC, BF percentage and WHR as compared to controls. However, the change in body weight, and WC was significant in subgroups of participants with insulin resistance related disorders, hypertension, obesity, magnesium deficiency at baseline, and females. We found a significant reduction in BMI following magnesium supplementation. The change in body weight and WC were evident in certain subgroups.

Magnesium intake in a Longitudinal Study of Adult Health: associated factors and the main food sources

This study aimed to identify the sociodemographic and lifestyle factors associated with magnesium intake and describe the main food sources in the Brazilian Longitudinal Study of Adult Health (ELSA-Brazil). This observational, cross-sectional study was conducted using the baseline data from the ELSA-Brazil (2008-2010). Associations between usual magnesium intake and sociodemographic and lifestyle factors were analyzed using multiple linear regression. Food sources were identified by calculating the percentage contribution of each FFQ item to the amount of magnesium provided by all foods. The analysis was performed using Stata® software (version 12), assuming a statistical significance level of 5%. The top food sources to magnesium intake were as follows: beans, oats, nuts, white rice, orange, French bread, cooked fish, boneless meat, whole milk, and whole wheat bread. There were positive associations between magnesium intake and female sex; age ≥60 years; self-reported black, indigenous, or brown skin colors; per capita income ≥3 minimum wages, and moderate or vigorous physical activity levels. Sociodemographic and lifestyle factors were associated with magnesium intake among the evaluated individuals.

Relationship Between Dietary Magnesium Intake and Incident Heart Failure Among Older Women: The WHI

Background

Women represent a large proportion of the growing heart failure (HF) epidemic, yet data are lacking regarding optimal dietary and lifestyle prevention strategies for them. Specifically, the association between magnesium intake and HF in a multiracial cohort of women is uncertain.

Methods and Results

We included 97 725 postmenopausal women from the WHI (Women's Health Initiative) observational studies and placebo arms of the hormone trial. Magnesium intake was measured at baseline by a 122‐item validated food‐frequency questionnaire and stratified into quartiles based on diet only, total intake (diet with supplements), and residual intake (calibration by total energy). Incident hospitalized HF (2153 events, median follow‐up 8.1 years) was adjudicated by medical record abstraction. In Cox proportional hazards models, we evaluated the association between magnesium intake and HF adjusting for potential confounders. Analyses were repeated on a subcohort (n=18 745; median‐follow‐up, 13.2 years) for whom HF cases were subclassified into preserved ejection fraction (526 events), reduced ejection fraction (291 events) or unknown (168 events). Most women were white (85%) with a mean age of 63. Compared with the highest quartile of magnesium intake, women in the lowest quartile had an increased risk of incident HF, with adjusted hazard ratios of 1.32 (95% CI, 1.02–1.71) for diet only (P trend=0.03), 1.26 (95% CI, 1.03–1.56) for total intake, and 1.31 (95% CI, 1.02–1.67) for residual intake. Results did not significantly vary by race. Subcohort analyses showed low residual magnesium intake was associated with HF with reduced ejection fraction (hazard ratio, 1.81, lowest versus highest quartile; 95% CI, 1.08–3.05) but not HF with preserved ejection fraction.

Conclusions

Low magnesium intake in a multiracial cohort of postmenopausal women was associated with a higher risk of incident HF, especially HF with reduced ejection fraction.

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.

The healthy Nordic diet for blood glucose control: a systematic review and meta-analysis of randomized controlled clinical trials

AIMS

Investigations on the possible effect of the Nordic diet (ND) on the glycemic control and the risk of diabetes have led to inconsistent results. The present study tried to determine the effect of the ND on the markers of blood glucose control using a systematic review and meta-analysis of randomized controlled clinical trials (RCTs).

METHODS

Predefined keywords were used to search PubMed, ISI Web of Science, Scopus and Google Scholar up to April 2019. The random effects model was used to compute the overall estimates.

RESULTS

In total, six RCTs with 618 participants (6-26 weeks of follow-up period) were included in the present study. The meta-analysis revealed that the ND might not have a considerable effect on fasting blood glucose levels [weighted mean difference (WMD) = -0.05 mmol/l, 95% CI - 0.13, 0.01, P = 0.112]. In contrast, the analyses showed that the ND significantly reduces serum insulin concentrations (WMD = -1.12 mU/l, 95% CI - 1.84, - 0.39, P = 0.002) and the homeostasis model assessment for insulin resistance (HOMA-IR) (WMD = - 0.34, 95% CI - 0.53, - 0.14, P = 0.001) compared to control diets. The effect on serum insulin levels was sensitive to one of the included studies. This dietary pattern did not significantly affect 2-h post-prandial blood glucose and Matsuda index.

CONCLUSIONS

Adherence to the ND might improve serum insulin and HOMA-IR levels; however, this effect was not confirmed for other markers of blood glucose control. Future well-designed and long-term clinical trials are highly recommended.

Effect of micronutrient malnutrition on periodontal disease and periodontal therapy

Periodontitis is a complex chronic inflammatory noncommunicable disease, initiated by the development of a dysbiotic microbial plaque biofilm below the gingival margin. Whilst the pathogenic biofilm is a "necessary cause" of periodontitis, it is insufficient on its own to cause the disease, and a destructive immune-inflammatory response is a key to the translation of risk to destructive events. Other exposures or "component causes" include individual genetic predisposition, lifestyle (including smoking and nutrition), and environmental factors. Dietary nutrients are essential for life as they provide crucial energy sources in the form of macronutrients, as well as important cofactors in the form of micronutrients, which regulate the functionality of enzymes during the regulation of anabolic and catabolic processes in human cells. Moreover, micronutrients can regulate gene transcription factors, such as the proinflammatory nuclear factor kappa B and the anti-inflammatory nuclear factor (erythroid-derived 2)-like 2. This review focuses on the role of vitamins (vitamin A, carotenoids, the vitamin B complex, vitamins C, D, and E, and coenzyme Q10) and minerals (calcium, magnesium, iron, zinc, potassium, copper, manganese, and selenium) in human physiology and the impact of their deficiencies upon periodontal health and disease.

Heart Failure With Preserved Ejection Fraction: Prevention and Management

Heart failure with preserved ejection fraction (HFpEF) is a complex clinical syndrome that constitutes nearly half of all heart failure cases. Because of lack of effective pharmacological targets to improve outcomes, the emphasis of the management and prevention of HFpEF should be through control of risk factors. This review will use the framework proposed by the American Heart Association on 7 simple measures ("Life's Simple 7") that involves diet and lifestyle changes to achieve ideal cardiovascular health. These 7 measures include (1) smoking, (2) obesity, (3) exercise, (4) diet, (5) blood pressure, (6) cholesterol, and (7) glucose control, which can help control the most common comorbidities and risk factors associated with HFpEF, such as hypertension, diabetes, and obesity. Therefore, application of these 7 simple measures would be a patient-centered and cost-effective way of prevention and management of HFpEF.

Blood and dietary magnesium levels are not linked with lower prostate cancer risk in black or white men

Recent studies suggest a diet low in dietary magnesium intake or lower blood magnesium levels is linked with increased prostate cancer risk. This study investigates the race-specific link between blood magnesium and calcium levels, or dietary magnesium intake, and the diagnosis of low-grade and high-grade prostate cancer. The study included 637 prostate cancer cases and 715 biopsy-negative controls (50% black) recruited from Nashville, TN or Durham, NC. Blood was collected at the time of recruitment, and dietary intake was assessed by food frequency questionnaire. Percent genetic African ancestry was determined as a compliment to self-reported race. Blood magnesium levels and dietary magnesium intake were significantly lower in black compared to white men. However, magnesium levels or intake were not associated with risk of total prostate cancer or aggressive prostate cancer. Indeed, a higher calcium-to-magnesium diet intake was significantly protective for high-grade prostate cancer in black (OR = 0.66 (0.45, 0.96), p = 0.03) but not white (OR = 1.00 (0.79, 1.26), p = 0.99) men. In summary, there was a statistically significant difference in magnesium intake between black and white men, but the biological impact was unclear, and we did not confirm a lower prostate cancer risk associated with magnesium levels.

Reuniting overnutrition and undernutrition, macronutrients, and micronutrients

Over-nutrition and its late consequences are a dominant theme in medicine today. In addition to the health hazards brought on by over-nutrition, the medical community has recently accumulated a roster of health benefits with obesity, grouped under "obesity paradox." Throughout the world and throughout history until the 20^th century, under-nutrition was a dominant evolutionary force. Under-nutrition brings with it a mix of benefits and detriments that are opposite to and continuous with those of over-nutrition. This continuum yields J-shaped or U-shaped curves relating body mass index to mortality. The overweight have an elevated risk of dying in middle age of degenerative diseases while the underweight are at increased risk of premature death from infectious conditions. Micronutrient deficiencies, major concerns of nutritional science in the 20^th century, are being neglected. This "hidden hunger" is now surprisingly prevalent in all weight groups, even among the overweight. Because micronutrient replacement is safe, inexpensive, and predictably effective, it is now an exceptionally attractive target for therapy across the spectrum of weight and age. Nutrition-related conditions worthy of special attention from caregivers include excess vitamin A, excess vitamin D, and deficiency of magnesium.

Salts and energy balance: A special role for dietary salts in metabolic syndrome

BACKGROUND

Dietary salts sodium (Na⁺), potassium (K⁺), magnesium (Mg2⁺), and calcium (Ca2⁺) are important in metabolic diseases. Yet, we do not have sufficient understanding on the salts global molecular network in these diseases. In this systematic review we have pooled information to identify the general effect of salts on obesity, insulin resistance and hypertension.

AIMS

To assess the roles of salts in metabolic disorders by focusing on their individual effect and the network effect among these salts.

METHODS

We searched articles in PubMed, EMBASE and Google Scholar. We selected original laboratory research, systematic reviews, clinical trials, observational studies and epidemiological data that focused on dietary salts and followed the preferred reporting items for systematic review in designing the present systematic review.

RESULTS

From the initial search of 2898 studies we selected a total of 199 articles that met our inclusion criteria and data extraction. Alterations in metabolic pathways associated with the sensitivity of sodium, potassium, magnesium and calcium may lead to obesity, hypertension, and insulin resistance. We found that the results of most laboratory research, animal studies and clinical trials are coherent but some research outcome are either inconsistent or inconclusive.

CONCLUSION

Important of salts in metabolic disorder is evident. In order to assess the effects of dietary salts in metablic diseases, environmental factors, dietary habits, physical activity, and the microbiome, should be considered in any study. Although interest in this area of research continues to grow, the challenge is to integrate the action of these salts in metabolic syndrom.

Dietary magnesium deficiency impaired intestinal structural integrity in grass carp (Ctenopharyngodon idella)

Grass carp (223.85–757.33 g) were fed diets supplemented with magnesium (73.54–1054.53 mg/kg) for 60 days to explore the impacts of magnesium deficiency on the growth and intestinal structural integrity of the fish. The results demonstrated that magnesium deficiency suppressed the growth and damaged the intestinal structural integrity of the fish. We first demonstrated that magnesium is partly involved in (1) attenuating antioxidant ability by suppressing Nrf2 signalling to decrease antioxidant enzyme mRNA levels and activities (except CuZnSOD mRNA levels and activities); (2) aggravating apoptosis by activating JNK (not p38MAPK) signalling to upregulate proapoptotic protein (Apaf-1, Bax and FasL) and caspase-2, -3, -7, -8 and -9 gene expression but downregulate antiapoptotic protein (Bcl-2, IAP and Mcl-1b) gene expression; (3) weakening the function of tight junctional complexes (TJs) by promoting myosin light chain kinase (MLCK) signalling to downregulate TJ gene expression [except claudin-7, ZO-2b and claudin-15 gene expression]. Additionally, based on percent weight gain (PWG), against reactive oxygen species (ROS), against caspase-9 and claudin-3c in grass carp, the optimal dietary magnesium levels were calculated to be 770.38, 839.86, 856.79 and 811.49 mg/kg, respectively.

Uromodulin regulates renal magnesium homeostasis through the ion channel transient receptor potential melastatin 6 (TRPM6)

Up to 15% of the population have mild to moderate chronic hypomagnesemia, which is associated with type 2 diabetes mellitus, hypertension, metabolic syndrome, and chronic kidney disease. The kidney is the key organ for magnesium homeostasis, but our understanding of renal magnesium regulation is very limited. Uromodulin (UMOD) is the most abundant urinary protein in humans, and here we report that UMOD has a role in renal magnesium homeostasis. Umod-knockout (Umod ^-/-) mice excreted more urinary magnesium than WT mice and displayed up-regulation of genes promoting magnesium absorption. The majority of magnesium is absorbed in the thick ascending limb. However, both mouse strains responded similarly to the diuretic agent furosemide, indicating appropriate function of the thick ascending limb in the Umod ^-/- mice. Magnesium absorption is fine-tuned in the distal convoluted tubule (DCT) via the apical magnesium channel transient receptor potential melastatin 6 (TRPM6). We observed decreased apical Trpm6 staining in the DCT of Umod ^-/- mice. Applying biotinylation assays and whole-cell patch-clamp recordings, we found that UMOD enhances TRPM6 cell-surface abundance and current density from the extracellular space. UMOD physically interacted with TRPM6 and thereby impaired dynamin-dependent TRPM6 endocytosis. WT mice fed a low-magnesium diet had an increased urinary UMOD secretion compared with the same mice on a regular diet. Our results suggest that increased urinary UMOD secretion in low-magnesium states reduces TRPM6 endocytosis and thereby up-regulates TRPM6 cell-surface abundance to defend against further urinary magnesium losses.

The Resulting Variation in Nutrient Intake With the Inclusion of Walnuts in the Diets of Adults at Risk for Type 2 Diabetes: A Randomized, Controlled, Crossover Trial

PURPOSE

We previously demonstrated that including walnuts in the diets of adults at risk for type 2 diabetes mellitus (T2DM) led to improved overall diet quality. This report examines the specific changes in their nutrient intake.

DESIGN

This was a randomized, controlled, modified Latin square parallel design trial with 2 treatment arms. Participants were randomized to walnut intake with, or without, dietary advice to regulate caloric intake. Within each treatment arm, they were further randomized to one of 2 sequence permutations (walnut-included/walnut-excluded or walnut-excluded/walnut-included diet), with a 3-month washout between treatment phases.

SETTING

Community hospital in Lower Naugatuck Valley in Connecticut.

PARTICIPANTS

Cohort of 112 participants (31 men and 81 women) at risk for T2DM.

INTERVENTION

Participants included 56 g (366 kcal) of walnuts in their daily diets for 6 months.

MEASURES

Nutrient intake was assessed using web-based Automated Self-Administered 24-Hour Dietary Assessment.

ANALYSIS

Data were analyzed using generalized linear models.

RESULTS

Walnut inclusion led to increased intake of total fat, calcium, magnesium, thiamin, total saturated fatty acids, and monounsaturated and polyunsaturated fatty acids (379.0 ± 90.3 g vs -136.5 ± 92.7 g, P < .01; 230.7 ± 114.2 mg vs -95.2 ± 117.4 mg, P = .05; 111.0 ± 33.9 mg vs -32.3 ± 34.9 mg, P < .01; 0.28 ± 0.2 mg vs -0.47 ± 0.2 mg, P = .02; 8.6 ± 3.4 g vs -1.1 ± 3.5 g, P =.05; 6.3 ± 3.9 g vs -6.3 ± 4.0 g, P = .03; and 25.4 ± 4.0 vs -6.6 ± 4.2 g, P < .01, respectively). Vitamin C intake decreased (-65.3 ± 55.3 mg vs 98.9 ± 56.8 mg, P = .04). Protein intake increased from baseline with the inclusion of walnuts (20.0 ± 8.8 g, P < .05). Walnut inclusion led to an increase in total calories consumed when caloric intake is not regulated.

CONCLUSION

Including walnuts in the diets of these adults led to increased dietary intake of some nutrients associated with lower risk of developing T2DM and other cardiometabolic risk factors.

Serum Magnesium after Kidney Transplantation: A Systematic Review

Magnesium (Mg) status has recently drawn close attention in chronic kidney disease and in kidney transplant recipients. This review aims to evaluate the body of evidence linking hypomagnesemia to clinical consequences in these specific populations. After a brief summary of the main mechanisms involved in Mg regulation and of Mg status in end-stage renal disease, the review focuses on the relationship between hypomagnesemia and cardiovascular risk in kidney transplant recipients. A body of evidence in recent studies points to a negative impact of hypomagnesemia on post-transplant diabetes mellitus (PTDM) and cardiovascular risk, which currently represent the main threat for morbidity and mortality in kidney transplantation. Deleterious biological mechanisms induced by hypomagnesemia are also discussed. While data analysis enables us to conclude that hypomagnesemia is linked to the development of PTDM, studies prospectively evaluating the impact of hypomagnesemia correction after kidney transplantation are still lacking and needed.

Intakes of magnesium, calcium and risk of fatty liver disease and prediabetes

OBJECTIVE

Obesity and insulin resistance play important roles in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Mg intake is linked to a reduced risk of metabolic syndrome and insulin resistance; people with NAFLD or alcoholic liver disease are at high risk of Mg deficiency. The present study aimed to investigate whether Mg and Ca intakes were associated with risk of fatty liver disease and prediabetes by alcohol drinking status.

DESIGN

We analysed the association between Ca or Mg intake and fatty liver disease, prediabetes or both prediabetes and fatty liver disease in cross-sectional analyses.

SETTING

Third National Health and Nutrition Examination Survey (NHANES III) follow-up cohort of US adults.

SUBJECTS

Nationally representative sample of US adults in NHANES (n 13 489).

RESULTS

After adjusting for potential confounders, Mg intake was associated with approximately 30 % reduced odds of fatty liver disease and prediabetes, comparing the highest intake quartile v. the lowest. Mg intake may only be related to reduced odds of fatty liver disease and prediabetes in those whose Ca intake is less than 1200 mg/d. Mg intake may also only be associated with reduced odds of fatty liver disease among alcohol drinkers.

CONCLUSIONS

The study suggests that high intake of Mg may be associated with reduced risks of fatty liver disease and prediabetes. Further large studies, particularly prospective cohort studies, are warranted to confirm the findings.

Combination Treatment of Deep Sea Water and Fucoidan Attenuates High Glucose-Induced Insulin-Resistance in HepG2 Hepatocytes

Insulin resistance (IR) plays a central role in the development of several metabolic diseases, which leads to increased morbidity and mortality rates, in addition to soaring health-care costs. Deep sea water (DSW) and fucoidans (FPS) have drawn much attention in recent years because of their potential medical and pharmaceutical applications. This study investigated the effects and mechanisms of combination treatment of DSW and FPS in improving IR in HepG2 hepatocytes induced by a high glucose concentration. The results elucidated that co-treatment with DSW and FPS could synergistically repress hepatic glucose production and increase the glycogen level in IR-HepG2 cells. In addition, they stimulated the phosphorylation levels of the components of the insulin signaling pathway, including tyrosine phosphorylation of IRS-1, and serine phosphorylation of Akt and GSK-3β. Furthermore, they increased the phosphorylation of AMPK and ACC, which in turn decreased the intracellular triglyceride level. Taken together, these results suggested that co-treatment with DSW and FPS had a greater improving effect than DSW or FPS alone on IR. They might attenuate IR by targeting Akt/GSK-3β and AMPK pathways. These results may have some implications in the treatment of metabolic diseases.

Association of Plasma Magnesium with Prediabetes and Type 2 Diabetes Mellitus in Adults

Our study aimed to assess the associations of plasma magnesium with prediabetes and type 2 diabetes (T2D) among Chinese adults. We conducted a case-control analysis of 4447 participants: 867 newly diagnosed prediabetes patients, 1475 newly diagnosed T2D patients and 2105 normal glucose tolerance (NGT) individuals. In a subsample of 599 apparently healthy individuals, we measured plasma hs-CRP levels to examine their relation to plasma magnesium. Plasma magnesium and hs-CRP were measured by inductively coupled plasma mass spectrometry and an enzyme-linked immunosorbent assay, respectively. Plasma magnesium decreased from NGT to prediabetes to T2D, and was inversely associated with prediabetes and T2D. After adjustment for potential confounding factors, the ORs from the lowest to highest quartiles of plasma magnesium were 1, 0.57 (95%CI, 0.44–0.74), 0.49 (0.37–0.65) and 0.51 (0.37–0.70) for prediabetes, and 1, 0.26 (0.20–0.33), 0.15 (0.12–0.20) and 0.15 (0.11–0.20) for T2D. Consistently, plasma magnesium was inversely correlated with plasma hs-CRP in our subsample analysis; the geometric mean hs-CRP concentration for ascending quartiles of plasma magnesium were 1.29 (1.06–1.57), 1.16 (0.95–1.41), 1.00 (0.81–1.22), and 0.71 (0.58–0.88) mg/l. Plasma magnesium was independently and inversely associated with prediabetes and T2D in Chinese adults.

Can Magnesium Enhance Exercise Performance?

Magnesium (Mg) is an essential mineral that plays a critical role in the human body. It takes part in the process of energy metabolism and assists the maintenance of normal muscle function. A number of studies evaluated the association between Mg status/supplementation and exercise performance and found that the need for Mg increased as individuals’ physical activity level went up. Animal studies indicated that Mg might improve exercise performance via enhancing glucose availability in the brain, muscle and blood; and reducing/delaying lactate accumulation in the muscle. The majority of human studies focused on physiological effects in blood pressure, heart rate and maximal oxygen uptake (VO₂ max), rather than direct functional performances. Some cross-sectional surveys demonstrated a positive association between Mg status and muscle performance, including grip strength, lower-leg power, knee extension torque, ankle extension strength, maximal isometric trunk flexion, rotation, and jumping performance. Additionally, findings from intervention studies showed that Mg supplementation might lead to improvements in functional indices such as quadriceps torque. Moreover, Mg supplementation could improve gait speed and chair stand time in elderly women. This comprehensive review summarized the literature from both animal and human studies and aimed to evaluate scientific evidence on Mg status/supplementation in relation to exercise performance.