Magnesium Intake, Quality of Carbohydrates, and Risk of Type 2 Diabetes: Results From Three U.S. Cohorts

Assessing the impact of magnesium-based nutritional education on lipid profiles in individuals with type 2 diabetes mellitus: a quasi-experimental study

BACKGROUND

The potential therapeutic role of magnesium (Mg) in type 2 diabetes mellitus (T2DM) remains insufficiently studied despite its known involvement in critical processes like lipid metabolism and insulin sensitivity. This study examines the impact of Mg-focused nutritional education on lipid profile parameters, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in T2DM patients.

METHODS

Thirty participants with T2DM were recruited for this within-subject experimental study. Participants underwent a three-month dietary intervention focused on increasing the intake of Mg-rich foods through nutritional education. Anthropometric measurements and lipids were assessed at baseline and after the intervention period, with the primary outcome variables including changes in lipid parameters.

RESULTS

The findings showed a significant inverse association between dietary Mg intake and total cholesterol levels (r = - 0.36, p = 0.05). However, other parameters, TG, LDL-C, and HDL-C, were not found to be associated with Mg intake.

CONCLUSION

The study demonstrated an inverse association between Mg intake and cholesterol level. Providing nutritional education and guidance on incorporating Mg-rich foods into the diet may be a crucial strategy for improving the health and well-being of T2DM patients in Saudi Arabia. The feasibility and practicality of focused nutritional education as an intervention make it a low-cost, scalable, and sustainable approach that can be readily implemented in clinical and community settings. Further studies are needed to explore the long-term impact of dietary Mg interventions on a larger sample with longer education periods.

The association between chemosensitivity and the 10-year risk of type 2 diabetes in male patients with obstructive sleep apnea

PURPOSE

Obstructive sleep apnea (OSA) is associated with a variety of diseases, including type 2 diabetes (T2D). Chemosensitivity is an important component of the pathophysiological mechanisms of OSA, and it is not only elevated in patients with OSA but also in those with T2D. This study aimed to investigate the association between chemosensitivity and the risk of developing T2D in patients with OSA.

METHODS

A total of 135 male participants with OSA and without pre-existing T2D were enrolled in this study. Peripheral chemosensitivity was evaluated using the rebreathing test. Data on demographics, polysomnographic parameters, and clinical characteristics were collected. The QDiabetes-2018 risk calculator was employed to calculate the 10-year T2D risk. The association between peripheral chemosensitivity and 10-year T2D risk was examined using multivariate logistic regression.

RESULTS

A total of 64 participants had moderate-to-high 10-year risk of T2D. In the fully adjusted model, participants situated within the second and fifth quantiles of peripheral chemosensitivity levels demonstrated a higher risk of developing T2D, with OR of 4.87 (95% CI, 1.22-19.43) and 5.26 (95% CI, 1.27-21.68) respectively. However, across varying levels of peripheral chemosensitivity, no significant difference in the 10-year T2D risk was observed among different severities of OSA.

CONCLUSION

Higher peripheral chemosensitivity was associated with an increased 10-year T2D risk, as calculated using a risk calculator based on clinical variables. For outcomes that reflect a moderate-to-high 10-year risk of T2D, the severity of OSA did not significantly affect the risk, irrespective of whether patients exhibited relatively low or high chemosensitivity.

Dietary Potassium and Magnesium Intake with Risk of Type 2 Diabetes Mellitus Among Rural China: the Henan Rural Cohort Study

Previous studies exploring the relationship between dietary potassium and magnesium intake and the risk of type 2 diabetes mellitus (T2DM) have yielded inconsistent results and the lack evidence from rural China. Therefore, we aimed to investigate the association between dietary potassium and magnesium intake and the risk of T2DM in rural China. Data was collected from the Henan Rural Cohort Study in 2017. A validated semi-quantitative food frequency questionnaire assessed dietary potassium and magnesium intake. Logistic regression models were used to calculate odds ratio (ORs) and 95% confidence intervals (CIs) to evaluate the effect of dietary potassium, magnesium and the potassium-magnesium ratio on the risk of T2DM. A total of 38384 individuals were included in the study, and 3616 participants developed T2DM. Logistic regression analysis revealed that the OR (95% CI) of the highest versus dietary potassium and magnesium and potassium-magnesium ratio intakes were 0.67 (0.59, 0.75), 0.76 (0.67, 0.88), and 0.57 (0.50, 0.66), respectively, compared to the subjects with the lowest quartile of intakes. In addition, gender partially influences the relationship between dietary magnesium and T2DM prevalence (P-interaction = 0.042). The group with the highest dietary potassium and dietary magnesium intake had the lowest risk of T2DM, with an OR (95% CI) of 0.63 (0.51-0.77). Dietary potassium and magnesium intake are important modifiable risk factors for T2DM in rural China. Dietary potassium intake > 1.8g/day, dietary magnesium intake > 358.6mg/day and < 414.7mg/day and potassium-magnesium ratio >5.1 should be encouraged to prevent better and manage T2DM.

The interaction between estimated glomerular filtration rate and dietary magnesium intake and its effect on stroke prevalence: a cross-sectional study spanning 2003-2018

Background

Despite the known associations of dietary magnesium intake and estimated glomerular filtration rate (eGFR) with cardiovascular diseases, their combined effects on stroke risk remain unclear. Therefore, this study aims to explore the associations of dietary magnesium intake and eGFR with stroke risk.

Methods

The National Health and Nutrition Examination Survey (NHANES) data of 37,637 adult participants (≥18 years) from 2003 to 2018 was analyzed. Dietary magnesium intake was categorized as low (≤ 254 mg/day) and normal (> 254 mg/day) based on experimental data. Multiple logistic regression analyses and interaction tests were conducted to assess the associations of dietary magnesium intake and eGFR with stroke risk, with a focus on the interaction between different chronic kidney disease (CKD) stages based on eGFR levels and dietary magnesium intake. Additional analyses included multiplicative interaction analysis, restricted cubic spline analysis, and subgroup evaluations by age, sex, and ethnicity.

Results

Dietary magnesium intake and eGFR were inversely correlated with the risk of stroke. Participants with low dietary magnesium intake had a higher stroke risk than those with normal magnesium intake (odds ratio [OR] 1.09, 95% confidence interval [CI]: 1.03-1.42). Likewise, low eGFR was associated with an elevated stroke risk compared with normal eGFR (OR 1.56, 95% CI: 1.15-2.13). Furthermore, the two factors showed a multiplicative interaction effect on stroke risk (OR 1.05, 95% CI: 1.01-1.09). We observed a significant interaction between stage G3 CKD and low dietary magnesium intake (OR 1.05, 95% CI: 1.01-1.09), suggesting a potential association with stroke risk. However, similar associations were not observed for stages G4 and G5, possibly due to the smaller number of participants with G4 and G5 CKD. The restricted cubic spline analysis revealed a non-linear relationship between dietary magnesium intake, eGFR, and stroke risk. The interaction between magnesium deficiency and low eGFR persisted in participants aged >60 years, as well as in females, non-Hispanic Black people, and people of other races.

Conclusion

Dietary magnesium intake and eGFR correlate negatively with stroke prevalence. Moreover, there was an interaction between dietary magnesium intake and stroke prevalence across different CKD stages. Further large-scale prospective studies are needed to analyze the potential relationship between dietary magnesium intake, eGFR, and stroke.

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.

Systematic Review and Meta-Analysis to Estimate a Reference Range for Circulating Ionized Magnesium Concentrations in Adult Populations

BACKGROUND

There is a lack of consensus on a reference range for ionized magnesium (iMg2+) in blood as a measure of the status of circulating iMg2+ for the screening of populations.

OBJECTIVES

We estimated the reference range of iMg2+ levels for healthy adult populations and the ranges for populations with cardiovascular disease (CVD), type 2 diabetes, hypertension, and renal disease. We also estimated 95% ranges for circulating magnesium (Mg) in healthy and those with cardiometabolic diseases.

METHODS

We searched Ovid MEDLINE, Cochrane Central Register of Controlled Trials, and Embase through 24 July, 2020 to identify articles. We included English, peer-reviewed, randomized controlled trials, prospective and retrospective cohort studies, case-control studies, and cross-sectional studies that measured iMg2+ in blood or circulating Mg at baseline. The protocol was registered on PROSPERO (CRD42020216100). Estimated ranges were calculated by employing a frequentist random-effects model using extracted (or calculated) means and SDs from each included study. We determined the 95% confidence interval of the pooled mean.

RESULTS

A total of 95 articles were included with 53 studies having data for healthy participants and 42 studies having data for participants with cardiometabolic diseases. The estimated reference range for iMg2+ for healthy populations was 0.40-0.68 mmol/L, 0.38-0.64 mmol/L for CVD, 0.34-0.66 mmol/L for type 2 diabetes, 0.39-1.04 mmol/L for hypertension, and 0.40-0.76 mmol/L for renal disease. For circulating Mg, the estimated range was 0.72-1.0 mmol/L for healthy adults, 0.56-1.05 mmol/L for CVD, 0.58-1.14 mmol/L for type 2 diabetes, 0.60-1.08 mmol/L for hypertension, and 0.59-1.26 mmol/L for renal disease.

CONCLUSIONS

Estimated reference ranges for cardiometabolic disease states for both iMg2+ and circulating Mg were broad and overlapped with the estimated range for healthy populations (0.40-0.68 mmol/L). Further studies should evaluate whether iMg2+ can be used as a biomarker of cardiometabolic disease.

Neo-Traditional and Industrialized Dietary Patterns Coexist and Are Differentially Associated with Cardiometabolic Health among Adults in Puerto Rico

BACKGROUND

An increasingly industrialized food system has marginalized local, traditional food cultures in Puerto Rico (PR). Recent efforts to decolonize diets have promoted local food intake; however, how resulting dietary patterns may influence cardiometabolic disease remains unknown.

OBJECTIVES

This study aimed to 1) identify dietary patterns in PR and 2) determine their associations with metabolic syndrome (MetS) and its components.

METHODS

Data were obtained from participants (30-75 y) in PROSPECT (PR Observational Study of Psychosocial, Environmental, and Chronic Disease Trends; n = 989). Dietary patterns were derived using partial least squares analysis with food frequency questionnaire data, using nutrients associated with local food purchasing (dietary fiber, magnesium, saturated fat) as response variables. MetS was classified using harmonized criteria from clinical and laboratory measures and medication use. Fully adjusted generalized linear models tested associations between tertiles of dietary patterns and MetS.

RESULTS

Approximately half (52%) of the participants were classified with MetS. Four dietary patterns were revealed: conventional (legumes, coffee, and dairy), industrialized starch and meat-centric (red/processed meats, pasta, and starchy roots), industrialized sugar-centric (rice, sugary beverages, and refined grains), and neo-traditional (local plants and seafood). Individuals in the highest (compared with lowest) tertile of the industrialized starch and meat-centric dietary pattern had higher mean waist circumference (102 compared with 99 cm) (P = 0.01), fasting glucose (106 compared with 98 mg/dL) (P = 0.019), and systolic blood pressure (123 compared with 119 mmHg) (P = 0.022). Individuals in the highest (compared with lowest) tertile of the neo-traditional diet were 0.69 (0.49, 0.97) times less likely to have MetS (P = 0.035) and had 4.1 cm lower mean waist circumference (P = 0.002).

CONCLUSIONS

Promoting a neo-traditional diet and curbing industrialized starch and meat-centric diets may improve cardiometabolic health in PR. Results can guide local food promotion as a healthful, decolonizing approach in island settings.

Magnesium and Liver Metabolism Through the Lifespan

Within the organism, the liver is the main organ responsible for metabolic homeostasis and xenobiotic transformation. To maintain an adequate liver weight-to-bodyweight ratio, this organ has an extraordinary regenerative capacity and is able to respond to an acute insult or partial hepatectomy. Maintenance of hepatic homeostasis is crucial for the proper functioning of the liver, and in this context, adequate nutrition with macro- and micronutrient intake is mandatory. Among all known macro-minerals, magnesium has a key role in energy metabolism and in metabolic and signaling pathways that maintain liver function and physiology throughout its life span. In the present review, the cation is reported as a potential key molecule during embryogenesis, liver regeneration, and aging. The exact role of the cation during liver formation and regeneration is not fully understood due to its unclear role in the activation and inhibition of those processes, and further research in a developmental context is needed. As individuals age, they may develop hypomagnesemia, a condition that aggravates the characteristic alterations. Additionally, risk of developing liver pathologies increases with age, and hypomagnesemia may be a contributing factor. Therefore, magnesium loss must be prevented by adequate intake of magnesium-rich foods such as seeds, nuts, spinach, or rice to prevent age-related hepatic alterations and contribute to the maintenance of hepatic homeostasis. Since magnesium-rich sources include a variety of foods, a varied and balanced diet can meet both macronutrient and micronutrient needs.

Magnesium Depletion Score Predicts Diabetic Retinopathy Risk among Diabetes: Findings from NHANES 2005-2018

Magnesium is essential for material and energy metabolism. The magnesium depletion score (MDS) is recognized as a more valuable and reliable predictor of body magnesium status than any other clinical used markers such as serum and urine magnesium. However, research on the relationship between MDS and diabetic retinopathy (DR) is limited. As a result, the current study sought to assess this issue in diabetic samples from a large population-based database in the United States. Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. MDS was calculated, and multivariate logistic regression analysis was applied to evaluate the presence of association between variables and DR risk. A total of 4308 participants was comprised in this study. Samples with DR consumed less magnesium (259.1 ± 113.6 vs 269.8 ± 113.2 mg, P < 0.001), and their MDS levels differed significantly from non-DR participants (P < 0.001). Increased dietary magnesium was linked to a lower incidence of DR (all P for trend < 0.05), and patients with a high level of MDS were more prone to DR (P = 0.001). Furthermore, subgroup analysis revealed that high (Q3) amount magnesium supplements was associated with lower DR risk when MDS was none to low or middle level (both P = 0.02). Our results indicated that MDS levels are associated with DR risk and that magnesium supplementation is benefit to DR prevention.

Higher magnesium levels are associated with better glycaemic control and diabetes remission post-bariatric surgery

BACKGROUND

Low Magnesium (Mg) dietary intake has been associated with increased risk of type 2 diabetes mellitus (T2DM). Furthermore, in patients with T2DM, hypomagnesemia is associated with worst glycaemic control. Bariatric surgery (BS) remains the most effective treatment in severe obesity and also provides resolution/improvement of T2DM. Our aim is to evaluate the association between Mg supplementation post-BS and Mg serum levels with diabetes status after BS.

METHODS

We performed an observational study on patients with obesity and T2DM who underwent BS. Data was assessed pre-BS and one-year post-BS.

RESULTS

We included a total of 403 patients with T2DM. At baseline, 43.4% of the patients had Mg deficiency. Pre-BS, patients with Mg deficiency had poorer glycaemic control - HbA1c 7.2 ± 1.6% vs 6.4 ± 1.0% (p < 0.001), fasting plasma glucose 146.2 ± 58.8 mg/dL vs 117.5 ± 36.6 mg/dL (p < 0.001) and were under a greater number of anti-diabetic drugs 1.0 (IQR 0-2.0) vs 1.0 (IQR 0-1.0) (p = 0.002). These findings persisted at one-year post-BS. At the first-year post-BS, 58.4% of the patients had total remission of T2DM and 4.1% had partial remission. Patients without Mg deficiency at one-year post-BS had higher rates of total and partial remission. Higher serum Mg levels at baseline is an independent predictor of total T2DM remission (p < 0.0001). The optimal cut-off of baseline Mg to predict total T2DM remission was 1.50 mg/dL with a sensitivity of 73% and a specificity of 58% (area under ROC = 0.65). Patients that were under Mg supplementation post-BS had serum Mg values, glycaemic control and total remission of T2DM similar to patients non-supplemented.

CONCLUSION

In patients with T2DM submitted to BS, higher Mg serum levels at baseline and 1-year after BS were associated with better glycaemic control and higher rates of total T2DM remission at the first year post-BS.

Magnesium Supplementation Is Associated with a Lower Cardio-Metabolic Risk in Patients Submitted to Bariatric Surgery

PURPOSE

Literature has demonstrated an inverse relation between magnesium (Mg) consumption and development of type 2 diabetes mellitus (T2DM), hypertension (HT), and dyslipidemia. After bariatric surgery (BS), micronutrients deficiencies are common, it being important to ensure appropriate supplementation. There is no recommendation about Mg supplementation and to our knowledge, its effect has not been studied to date. Our aim was to evaluate the effect of Mg supplementation in cardio-metabolic risk factors on post-bariatric patients.

MATERIALS AND METHODS

A retrospective observational study of patients with obesity who underwent BS was performed. Data was assessed preoperatively and yearly (4-year follow-up).

RESULTS

A total of 3363 patients were included. In the first year of follow-up, 79.8% (n = 2123) of the patients were supplemented with Mg, with evidence of slightly decreased percentages in the following years. Mg deficiency (serum Mg < 1.52 mEq/L) was more common among patients who were not supplemented during each year of follow-up (p < 0.05). Among those who underwent Mg supplementation, the percentage of T2DM, HT, or low-density lipoprotein cholesterol (LDL-C) > 130 mg/dL was significantly lower. In the first year post-surgery, the supplementation group had a lower risk of T2DM (OR = 0.545, p < 0.0001), LDL-C > 130 mg/dL (OR = 0.612, p < 0.0001), and HT (OR = 0.584, p < 0.0001). The OR for having these metabolic comorbidities persisted lower during the 4 years' follow-up. Patients who had Mg deficiency had higher prevalence of T2DM and HT.

CONCLUSION

Mg supplementation seems to have a protective effect on the development of T2DM, HT, and LDL-C > 130 mg/dL in post-bariatric patients.

The Role of Magnesium in the Pathogenesis of Metabolic Disorders

Magnesium (Mg) is an essential nutrient for maintaining vital physiological functions. It is involved in many fundamental processes, and Mg deficiency is often correlated with negative health outcomes. On the one hand, most western civilizations consume less than the recommended daily allowance of Mg. On the other hand, a growing body of evidence has indicated that chronic hypomagnesemia may be implicated in the pathogenesis of various metabolic disorders such as overweight and obesity, insulin resistance (IR) and type 2 diabetes mellitus (T2DM), hypertension (HTN), changes in lipid metabolism, and low-grade inflammation. High Mg intake with diet and/or supplementation seems to prevent chronic metabolic complications. The protective action of Mg may include limiting the adipose tissue accumulation, improving glucose and insulin metabolism, enhancing endothelium-dependent vasodilation, normalizing lipid profile, and attenuating inflammatory processes. Thus, it currently seems that Mg plays an important role in developing metabolic disorders associated with obesity, although more randomized controlled trials (RCTs) evaluating Mg supplementation strategies are needed. This work represents a review and synthesis of recent data on the role of Mg in the pathogenesis of metabolic disorders.

Effect of the Consumption of Alcohol-Free Beers with Different Carbohydrate Composition on Postprandial Metabolic Response

Background: We investigated the postprandial effects of an alcohol-free beer with modified carbohydrate (CH) composition compared to regular alcohol-free beer. Methods: Two randomized crossover studies were conducted. In the first study, 10 healthy volunteers received 25 g of CH in four different periods, coming from regular alcohol-free beer (RB), alcohol-free beer enriched with isomaltulose and a resistant maltodextrin (IMB), alcohol-free beer enriched with resistant maltodextrin (MB), and a glucose-based beverage. In the second study, 20 healthy volunteers were provided with 50 g of CH from white bread (WB) plus water, or with 14.3 g of CH coming from RB, IMB, MB, and extra WB. Blood was sampled after ingestion every 15 min for 2 h. Glucose, insulin, incretin hormones, TG, and NEFAs were determined in all samples. Results: The increase in glucose, insulin, and incretin hormones after the consumption of IMB and MB was significantly lower than after RB. The consumption of WB with IMB and MB showed significantly less increase in glucose levels than WB with water or WB with RB. Conclusions: The consumption of an alcohol-free beer with modified CH composition led to a better postprandial response compared to a conventional alcohol-free beer.

Nutritional composition and proteomic analysis of soft-shelled turtle (Pelodiscus sinensis) egg and identification of oligopeptides with alpha-glucosidase inhibitory activity

This study aimed to explore nutritional compositions and proteomics of soft-shelled turtle (SST) egg, as well as identify potential antidiabetic oligopeptides with α-glucosidase inhibitory property. Results revealed that SST egg is a promising source of highly nutritious proteins and minerals (54.64% and 5.81% of dry matter, respectively). Further proteomic analysis showed SST egg proteins contained at least 9 protein families, such as transferrin/iron binding protein and immunoregulation-related protein. Hydrolysis by different enzymes, especially papain, remarkably increased α-glucosidase inhibitory activity and scavenging activity for ABTS, DPPH, hydroxyl and oxygen radicals of SST egg proteins. Peptides from papain hydrolysate were fractionated using ultrafiltration followed by reverse phase chromatography, and 16 peptides were identified in the most active fraction by LC-QTOF-MS/MS. Molecular docking revealed that 14 of these peptides could easily dock into the substrate-binding pocket and/or inhibitor binding sites of α-glucosidase with the docking score below -150 kcal/mol, indicating their potential α-glucosidase inhibitory properties. The five most abundant oligopeptides with potent interaction with α-glucosidase were further synthesized, and oligopeptides HNKPEVEVR, ARDASVLK and SGTLLHK strongly inhibited the activity of α-glucosidase (IC₅₀ of 56, 195 and 289 µmol/L, respectively). Therefore, oligopeptides from enzymatic hydrolysate of SST egg protein exhibit potential antidiabetic activity, making it a promising functional food ingredient.

Integrative Management of Pancreatic Cancer (PDAC): Emerging Complementary Agents and Modalities

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease. The standard first-line treatment for PDAC is gemcitabine chemotherapy which, unfortunately, offers only limited chance of a lasting cure. This review further evaluates the hypothesis that the effectiveness of gemcitabine can be improved by combining it with evidence-based complementary measures. Previously, supported by clinical trial data, we suggested that a number of dietary factors and nutraceuticals can be integrated with gemcitabine therapy. Here, we evaluate a further 10 agents for which no clinical trials have (yet) been carried out but there are promising data from in vivo and/or in vitro studies including experiments involving combined treatments with gemcitabine. Two groups of complementary agents are considered: Dietary factors (resveratrol, epigallocatechin gallate, vitamin B9, capsaicin, quercetin and sulforaphane) and nutraceutical agents (artemisinin, garcinol, thymoquinone and emodin). In addition, we identified seven promising agents for which there is currently only basic (mostly in vitro) data. Finally, as a special case of combination therapy, we highlighted synergistic drug combinations involving gemcitabine with "repurposed" aspirin or metformin. We conclude overall that integrated management of PDAC currently is likely to produce the best outcome for patients and for this a wide range of complementary measures is available.

Crosstalk of Magnesium and Serum Lipids in Dyslipidemia and Associated Disorders: A Systematic Review

Dyslipidemia is a significant threat to public health worldwide and the identification of its pathogenic mechanisms, as well as novel lipid-lowering agents, are warranted. Magnesium (Mg) is a key element to human health and its deficiency has been linked to the development of lipid abnormalities and related disorders, such as the metabolic syndrome, type 2 diabetes mellitus, or cardiovascular disease. In this review, we explored the associations of Mg (dietary intake, Mg concentrations in the body) and the lipid profile, as well as the impact of Mg supplementation on serum lipids. A systematic search was computed in PubMed/MEDLINE and the Cochrane Library and 3649 potentially relevant papers were detected and screened (n = 3364 following the removal of duplicates). After the removal of irrelevant manuscripts based on the screening of their titles and abstracts (n = 3037), we examined the full-texts of 327 original papers. Finally, after we applied the exclusion and inclusion criteria, a number of 124 original articles were included in this review. Overall, the data analyzed in this review point out an association of Mg concentrations in the body with serum lipids in dyslipidemia and related disorders. However, further research is warranted to clarify whether a higher intake of Mg from the diet or via supplements can influence the lipid profile and exert lipid-lowering actions.

Health benefits of whole grain: effects on dietary carbohydrate quality, the gut microbiome, and consequences of processing

Grains are important sources of carbohydrates in global dietary patterns. The majority of these carbohydrates, especially in refined-grain products, are digestible. Most carbohydrate digestion takes place in the small intestine where monosaccharides (predominantly glucose) are absorbed, delivering energy to the body. However, a considerable part of the carbohydrates, especially in whole grains, is indigestible dietary fibers. These impact gut motility and transit and are useful substrates for the gut microbiota affecting its composition and quality. For the most part, the profile of digestible and indigestible carbohydrates and their complexity determine the nutritional quality of carbohydrates. Whole grains are more complex than refined grains and are promoted as part of a healthy and sustainable diet mainly because the contribution of indigestible carbohydrates, and their co-passenger nutrients, is significantly higher. Higher consumption of whole grain is recommended because it is associated with lower incidence of, and mortality from, CVD, type 2 diabetes, and some cancers. This may be due in part to effects on the gut microbiota. Although processing of cereals during milling and food manufacturing is necessary to make them edible, it also offers the opportunity to still further improve the nutritional quality of whole-grain flours and foods made from them. Changing the composition and availability of grain carbohydrates and phytochemicals during processing may positively affect the gut microbiota and improve health.

Magnesium in Obesity, Metabolic Syndrome, and Type 2 Diabetes

Magnesium (Mg²⁺) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg²⁺ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg²⁺ deficiency, such as the lack of a clear definition of Mg²⁺ nutritional status, the use of different Mg²⁺ salts and dosage and the different duration of the Mg²⁺ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg²⁺, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D.

The effect of perioperative magnesium sulfate on blood sugar in patients with diabetes mellitus undergoing cardiac surgery: A double-blinded randomized study

Objective

The aim of the present study was to evaluate the perioperative effect of magnesium infusion on blood sugar level in patients with diabetes mellitus undergoing cardiac surgery.

Design

This was a double-blind randomized study.

Setting

The study was conducted at cardiac center.

Patients

The study included 122 adult patients.

Intervention

Group M - The patients received a continuous infusion of magnesium sulfate (without a loading dose) at 15 mg/kg/h. The infusion rate was started 20 min before induction maintained during surgery and the first postoperative 24 h. The medication was prepared by adding 5 g magnesium sulfate in 50 ml syringe. Group C - The patients received equal amount of normal saline.

Measurements

The monitors included heart rate, mean arterial blood pressure, central venous pressure, urine output, blood levels of magnesium, sugar, and potassium.

Results

The blood sugar level and the required insulin significantly decreased with Group M than Group C (P < 0.05). There were minimal changes in the potassium level in Group M, but potassium decreased in patients of Group C (P < 0.05). The amount of urine output was too much higher in Group M than Group C (P < 0.05). The pharmacological and mechanical support significantly decreased with Group M than Group C (P < 0.05). The hospital and Intensive Care Unit length of stay significantly decreased with Group M than Group C (P < 0.05).

Conclusion

The magnesium sulfate produced a better-controlled effect on the blood sugar level. It decreased the requirement of insulin infusion and minimized the changes in the blood level of potassium.

Influence of Demographic and Lifestyle Variables on Plasma Magnesium Concentrations and Their Associations with Cardiovascular Risk Factors in a Mediterranean Population

Several studies have shown that a low magnesium (Mg) intake in the diet is associated with greater cardiovascular risk and greater risk of diabetes. However, the results are not consistent in all populations. To minimize the biases derived from diet measurement, more objective biomarkers of magnesium status have been proposed. Although there is still no ideal biomarker for Mg, several studies have shown that plasma Mg concentrations could be a relatively acceptable biomarker for cardiovascular risk assessment. However, further studies are required to better characterize this marker in different populations. Our aim was to analyze the association between plasma Mg concentrations (measured through inductively coupled plasma mass spectrometry (ICP-MS)) methods, and cardiovascular risk factors in individuals from a general Mediterranean population (aged 18–80 years). The influence of demographic and lifestyle variables, including adherence to the Mediterranean diet, on plasma Mg concentrations was analyzed. The mean Mg level of the population studied was 0.77 ± 0.08 mmol/L, the prevalence of hypomagnesemia (<0.70 mmol/L) being 18.6%. We did not find any statistically significant differences between plasma Mg concentrations and sex, age, tobacco smoking and total adherence to the Mediterranean diet (p > 0.05). We found a statistically significant association between plasma Mg concentrations and the prevalence of type-2 diabetes (0.77 ± 0.08 mmol/L in non-diabetics versus 0.73 ± 0.13 mmol/L in diabetics; p = 0.009). Despite the low prevalence of type-2 diabetes in this population (11.24% in subjects with hypomagnesemia versus 3.91%, in normomagnesemia; p = 0.005), hypomagnesemia was associated with greater odds of being diabetic in comparison with normomagnesemia (OR = 3.36; p = 0.016, even after adjustment for sex, age, obesity, and medications). On the other hand, no statistically significant association of plasma Mg concentrations with obesity, hypertension, fasting triglycerides, HDL-cholesterol or uric acid was found. However, in contrast to what was initially expected, a statistically significant association was found between plasma Mg concentrations (basically in the highest quartile) and greater total cholesterol (p < 0.05) and LDL-cholesterol concentrations (p < 0.05). In conclusion, our results contribute to increasing the evidence gathered by numerous studies on the inverse association between hypomagnesemia and type-2 diabetes, as well as to the observation, previously reported in some studies, of a direct association with hypercholesterolemia. This paradoxical link should be deeply investigated in further studies.

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.

Magnesium intake and primary liver cancer incidence and mortality in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial

Epidemiological studies on magnesium intake and primary liver cancer (PLC) are scarce, and no prospective studies have examined the associations of magnesium intake with PLC incidence and mortality. We sought to clarify whether higher magnesium intake from diet and supplements was associated with lower risks of PLC incidence and mortality in the US population. Magnesium intake from diet and supplements was evaluated through a food frequency questionnaire in a cohort of 104,025 participants. Cox regression was employed to calculate hazard ratios for PLC incidence and competing risk regression was employed to calculate subdistribution hazard ratios for PLC mortality. Restricted cubic spline regression was employed to test nonlinearity. We documented 116 PLC cases during 1,193,513.5 person-years of follow-up and 100 PLC deaths during 1,198,021.3 person-years of follow-up. Total (diet + supplements) magnesium intake was found to be inversely associated with risks of PLC incidence (hazard ratio_{tertile 3 vs. 1} : 0.44; 95% confidence interval: 0.24, 0.80; p_trend = 0.0065) and mortality (subdistribution hazard ratio_{tertile 3 vs. 1} : 0.37; 95% confidence interval: 0.19, 0.71; p_trend = 0.0008). Similar results were obtained for dietary magnesium intake. Nonlinear inverse dose-response associations with PLC incidence and mortality were observed for both total and dietary magnesium intakes (all p_nonlinearity  < 0.05). In summary, in the US population, a high magnesium intake is associated with decreased risks of PLC incidence and mortality in a nonlinear dose-response manner. These findings support that increasing the consumption of foods rich in magnesium may be beneficial in reducing PLC incidence and mortality.

Association of low serum magnesium with diabetes and hypertension: Findings from Qatar Biobank study

AIM

We aimed to examine the association between serum magnesium and diabetes and hypertension among Qatari adults.

METHODS

In the cross-sectional study, we used data from 9693 Qatari participants aged 20 years and above attending the Qatar Biobank (QBB) Study. Blood samples were analyzed in a central lab. Habitual food consumption was assessed by a food frequency questionnaire. Reduced rank regression was used to construct magnesium related dietary pattern (MRDP) using serum magnesium as a response variable. Diabetes was defined by blood glucose, HbA1c or known diabetes. Prediabetes was defined as HbA1c between 5.7% and 6.4%. Subclinical magnesium deficiency was defined as serum magnesium <0.85 mmol/L.

RESULTS

The prevalence of diabetes, prediabetes and subclinical magnesium deficiency was 18.9%, 11.5% and 59.5%, respectively. Across the quartiles of serum magnesium from high to low, the prevalence ratios (PR 95%CI) for diabetes were 1.00, 1.35, 1.88, and 2.70 (95%CI 2.38-3.05), respectively (p for trend <0.001). The presence of hypertension significantly increased the probability of diabetes along a wide range of low serum magnesium. A low intake of MRDP was also positively associated with diabetes and high HbA1c.

CONCLUSION

Subclinical magnesium deficiency is common in Qatar and associates with diabetes, prediabetes and hypertension in Qatari adults.

Diet and prevention of type 2 diabetes mellitus: beyond weight loss and exercise

INTRODUCTION

Insulin resistance (IR) and pancreatic beta-cell dysfunction are core pathophysiologic features of type 2 diabetes mellitus (T2DM). Select lifestyle and pharmacologic interventions, including weight loss, physical activity, a Mediterranean diet intervention, and hypoglycemic agents, have been shown to prevent or delay T2DM. However, dietary factors other than weight loss may also impact risk, mainly through effects to enhance insulin sensitivity, although some may also directly or indirectly impact pancreatic beta-cell function.

AREAS COVERED

A literature review of observational studies and randomized controlled trials (RCTs) was conducted, and the research indicates dietary factors showing promise for reducing T2DM risk include higher intakes of cereal fibers, unsaturated fatty acids, magnesium, and polyphenols (e.g. anthocyanins), while reducing dietary glycemic load, added sugars, and high-sugar beverages.

EXPERT COMMENTARY

While these dietary factors are mainly supported by evidence from observational studies and RCTs of surrogate markers for T2DM, they are consistent with current recommendations to emphasize consumption of whole grains, nuts, seeds, legumes, seafood, fruits, and vegetables, while limiting intakes of saturated fatty acids, refined carbohydrates, and processed meats. Additional dietary intervention RCTs are needed to assess the efficacy of these promising dietary interventions for delaying or preventing the onset of T2DM.

Changes in Trace Elements During Early Stages of Chronic Kidney Disease in Type 2 Diabetic Patients

Trace elements can influence glucose metabolism and be related to oxidative stress in type 2 diabetes mellitus. Moreover, trace elements play important roles in the nephrotic complications of these patients. Nevertheless, few investigations have been made into the changes in the levels of trace elements in diabetic patients at various stages of chronic kidney disease (CKD). The aims of this present study were to determine the levels of some important trace elements in diabetic patients during the early stages of CKD and to identify the relationship between these elements and CKD progression in type 2 diabetic patients. One hundred and forty-eight type 2 diabetic patients with chronic kidney diseases were recruited into this study. The subjects were grouped into four stages (1, 2, 3a, 3b) of CKD, according to their urine protein levels and estimated glomerular filtration rates (eGFRs). The levels of serum zinc and iron exhibited a statistically significant decreasing trend (P trend = 0.032 and 0.047, respectively) from stage 1 to stage 3b after adjustment for age, gender, smoking, alcohol consumption, education, hypertension, and body mass index. The other tested elements, including copper, magnesium, selenium, chromium, and manganese, did not display any significant trends upon proceeding from stage 1 to stage 3b. Thus, serum zinc and iron appear to be useful markers when evaluating the early progression of CKD in type 2 diabetic patients.

Dietary Magnesium and Cardiovascular Disease: A Review with Emphasis in Epidemiological Studies

Magnesium (Mg) is an essential dietary element for humans involved in key biological processes. A growing body of evidence from epidemiological studies, randomized controlled trials (RCTs) and meta-analyses have indicated inverse associations between Mg intake and cardiovascular diseases (CVD). The present review aims to summarize recent scientific evidence on the topic, with a focus on data from epidemiological studies assessing the associations between Mg intake and major cardiovascular (CV) risk factors and CVD. We also aimed to review current literature on circulating Mg and CVD, as well as potential biological processes underlying these observations. We concluded that high Mg intake is associated with lower risk of major CV risk factors (mainly metabolic syndrome, diabetes and hypertension), stroke and total CVD. Higher levels of circulating Mg are associated with lower risk of CVD, mainly ischemic heart disease and coronary heart disease. Further, RCTs and prospective studies would help to clarify whether Mg intake and Mg circulating levels may also protect against other CVDs and CVD death.