The 2015 Dietary Guidelines Advisory Committee indicated that magnesium was a shortfall nutrient that was underconsumed relative to the Estimated Ave

Trials and meta-analyses of oral magnesium for hypertension show promising but conflicting results. An inclusive collection of 49 oral magnesium for blood pressure (BP) trials were categorized into four groups: (1) Untreated Hypertensives; (2) Uncontrolled Hypertensives; (3) Controlled Hypertensives; (4) Normotensive subjects. Each group was tabulated by ascending magnesium dose. Studies reporting statistically significant (p < 0.05) decreases in both systolic BP (SBP) and diastolic BP (DBP) from both baseline and placebo (if reported) were labeled “Decrease”; all others were deemed “No Change.” Results: Studies of Untreated Hypertensives (20 studies) showed BP “Decrease” only when Mg dose was >600 mg/day; 600 mg/day). Where magnesium did not lower BP, other cardiovascular risk factors showed improvement. Conclusion: Controlled Hypertensives and Normotensives do not show a BP-lowering effect with oral Mg therapy, but oral magnesium (≥240 mg/day) safely lowers BP in Uncontrolled Hypertensive patients taking antihypertensive medications, while >600 mg/day magnesium is required to safely lower BP in Untreated Hypertensives; <600 mg/day for non-medicated hypertensives may not lower both SBP and DBP but may safely achieve other risk factor improvements without antihypertensive medication side effects.

In 1997, the US Institute of Medicine (IOM) dietary reference intakes (DRI) Committee established a magnesium (Mg) tolerable upper intake level (UL) for adults of 350 mg/d from supplemental intake alone. Diarrhea was the limiting factor. The safety of oral Mg dietary supplements exceeding the UL is currently in debate. Increasing the UL may result in more Mg supplementation, decreasing the prevalence of undernutrition for this nutrient and thus providing additional protection against numerous chronic diseases. This perspective aims to show that more recent and comprehensive evidence-based data on the occurrence of diarrhea indicate that the Mg UL for adults should be re-evaluated. To update the literature base to re-evaluate setting the Mg UL, a PubMed search was conducted to identify intervention studies published between 1997 and 2022 that used single-ingredient Mg products reporting a priori diarrhea adverse events among adults. The Food and Drug Administration Center for Food Safety and Adverse Event Reporting System (CAERS) was also searched for adverse events caused by Mg supplementation. The PubMed search identified 10 studies, including 5 meta-analyses and 5 randomized controlled trials, that met the search criteria. Seven studies (Mg intakes of 128-1200 mg/d) found no significant differences in diarrhea occurrence between the intervention and control groups. One meta-analysis found only minor differences in gastrointestinal disturbances between groups given placebo versus 520 mg Mg/d, but withdrawals were not significantly different between groups. Another meta-analysis found that 3 of 13 studies (120-973 mg/d) reported diarrhea that led to study withdrawal, but the treatment arm was not specified in 2 studies. The CAERS search, when limited to single-ingredient suspect Mg products, found only 40 attributable cases of gastrointestinal adverse events. Only one-third of these 40 cases noted a complaint of diarrhea. These updated data indicate that doses above the current UL for Mg supplements can be consumed without adverse events.

The US Dietary Guidelines for Americans (DGA) provide dietary recommendations to meet nutrient needs, promote health, and prevent disease. Despite 40 years of DGA, the prevalence of under-consumed nutrients continues in the US and globally, although dietary supplement use can help to fill shortfalls. Nutrient recommendations are based on Dietary Reference Intakes (DRIs) to meet the nutrient requirements for nearly all (97 to 98 percent) healthy individuals in a particular life stage and gender group and many need to be updated using current evidence. There is an opportunity to modernize vitamin and mineral intake recommendations based on biomarker or surrogate endpoint levels needed to ‘prevent deficiency’ with DRIs based on ranges of biomarker or surrogate endpoints levels that support normal cell/organ/tissue function in healthy individuals, and to establish DRIs for bioactive compounds. We recommend vitamin K and Mg DRIs be updated and DRIs be established for lutein and eicosapentaenoic and docosahexaenoic acid (EPA + DHA). With increasing interest in personalized (or precision) nutrition, we propose greater research investment in validating biomarkers and metabolic health measures and the development and use of inexpensive diagnostic devices. Data generated from such approaches will help elucidate optimal nutrient status, provide objective evaluations of an individual’s nutritional status, and serve to provide personalized nutrition guidance.

Background and Aims: Magnesium deficiency is associated with poor outcomes in patients with heart failure (HF), but less is known about the impact of oral magnesium therapy. This study aimed to examine the association of oral magnesium with outcomes in patients with HF and whether it depends on baseline serum magnesium. Methods: Of 54 696 Veterans with HF (2001–2023) and hypomagnesemia (serum magnesium <1.7 mg/dL), 10 695 were initiated on oral magnesium (median dose, 420 mg/day). A propensity score-matched cohort of 21 098 patients (treated, n = 10 549) balanced on 71 baseline characteristics was assembled while remaining outcome-blinded. This process was repeated to assemble a matched cohort of 11 634 patients (treated, n = 5817) with normomagnesemia (serum magnesium, 1.7–2.3 mg/dL). Hazard ratios (HR) (95% confidence intervals [CIs]) for one-year outcomes associated with oral magnesium were estimated. Results: In the hypomagnesemia cohort, HF hospitalization or death occurred in 21.7% of patients not receiving and 20.1% receiving oral magnesium (HR: 0.91; 95% CI: 0.86–0.97). Respective HRs (95% CIs) in subgroups with serum magnesium 1.6 (n = 5929), 1.3–1.5 (n = 11 293) and <1.3 (n = 3876) mg/dL were 0.99 (0.88–1.12), 0.91 (0.84–0.98; interaction P = .20), and 0.81 (0.71–0.93; interaction P = .03). Respective rates in the normomagnesemia cohort were 17.8% and 19.5% (HR: 1.11; 95% CI: 1.02–1.21). Spline regression analysis revealed that HRs were lower at serum magnesium 1.8 mg/dL, and not significant at 1.5–1.8 mg/dL. Conclusions: Oral magnesium therapy was associated with a lower risk of HF hospitalization or death in patients with HF and hypomagnesemia. Future clinical trials need to confirm these findings.