Magnesium levels overlooked

4 STUDIES!!

#1 

Magnesium levels overlooked 

The Daily Herald October 17, 2010  

A new study reports a protective effect against the risk of sudden cardiac death in women who consume higher levels of dietary magnesium. 

Researchers analyzed data from more than 88,000 women. Over the 26 year follow-up period, women whose magnesium intake was among the highest 25 percent of the subjects had a 34 percent lower adjusted risk of sudden cardiac death. 

According to the article in the American Journal of Clinical Nutrition: 

"Given that most Americans do not meet the RDA [recommended daily allowance] for magnesium, increasing intake of magnesium presents a potential opportunity for sudden cardiac death prevention in the general population."

Magnesium is a mineral that is important for health, but can it prevent sudden cardiac death? According to a recent medical study, the answer is yes.

Sudden cardiac death is a leading cause of heart-related deaths, especially in people 40 and older. According to the Centers for Disease Control and Prevention, SCD accounts for more than 250,000 deaths annually. That is more than colon cancer, breast cancer, prostate cancer and AIDS combined. 

The most common cause of SCD is believed to be a heart rhythm disorder or arrhythmia called ventricular fibrillation. Unfortunately, most people do not know if they are at risk. When the heart stops, cardiopulmonary resuscitation and immediate emergency medical care may be successful, but time is of the essence. The key is in prevention, and magnesium may be an answer. 

Magnesium is one of the most common elements in the human body and, indeed, the known universe. It is essential for life and therefore must be important. Hundreds of enzymes require magnesium, and it plays an important role in the production of energy and DNA function. 

While magnesium may be commonly used for constipation and as a soak for sore muscles, it is also a true muscle relaxant with anti-inflammatory properties. Interestingly, it can also stabilize abnormal nerve function and, given intravenously, can “break a migraine headache. Magnesium may also prevent heart arrhythmias associated with SCD. 

A recent medical study done at the University of Minnesota revealed that robust blood levels of magnesium significantly reduces the risk of SCD. This research, part of the Atherosclerosis Risk in Communities Study, looked at blood levels of magnesium and the risk of SCD over a 12-year period. They found that people who had the highest levels of magnesium in their blood had a 40 percent reduction in the risk of SCD compared to those whose blood magnesium levels where at the low end of the reference range. 

Risk factors for SCD include atherosclerotic heart disease, cardiomyopathies, abnormalities in the electrical pathways of the heart, toxins and low magnesium levels. Adequate levels are determined by a laboratory reference range. However, the range for magnesium is not necessarily the optimal range or even normal range. It is a mathematical average and may be too low for those at risk. 

Determining the level of magnesium is a simple blood test. However, magnesium levels can quickly change based on food and supplement use. A more accurate test is to look at magnesium levels in red blood cells. For my patients, most are at the low end of the reference range and need additional magnesium. 

Magnesium can be taken as a supplement, but also can be found in nuts, seeds, beans and whole grains. Although the most common side effect of magnesium is diarrhea, those with kidney or heart disease should be monitored by a physician if using magnesium supplements. 

Patrick B. Massey, M.D., Ph.D is medical director for complementary and alternative medicine for the Alexian Brothers Hospital Network. 

#2  

Plasma and dietary magnesium and risk of sudden cardiac death in women 

American Society for Clinical Nutrition 110.002253 November 24, 2010  

Supported by a research grant from Siemens Healthcare Diagnostics, an Established Investigator Award from the American Heart Association to CMA, and grants CA-87969, HL-34594, HL-03783, and HL-068070 from the National Institutes of Health. JLJ was supported in part by the Balson Cardiac Scholar Fund.

Abstract 

Background: Magnesium has antiarrhythmic properties in cellular and experimental models; however, its relation to sudden cardiac death (SCD) risk is unclear. 

Objective: We prospectively examined the association between magnesium, as measured in diet and plasma, and risk of SCD. 

Design: The analysis was conducted within the Nurses' Health Study. The association for magnesium intake was examined prospectively in 88,375 women who were free of disease in 1980. Information on magnesium intake, other nutrients, and lifestyle factors was updated every 2–4 y through questionnaires, and 505 cases of sudden or arrhythmic death were documented over 26 y of follow-up. For plasma magnesium, a nested case-control analysis including 99 SCD cases and 291 controls matched for age, ethnicity, smoking, and presence of cardiovascular disease was performed. 

Results: After multivariable adjustment for confounders and potential intermediaries, the relative risk of SCD was significantly lower in women in the highest quartile compared with those in the lowest quartile of dietary (relative risk: 0.63; 95% CI: 0.44, 0.91) and plasma (relative risk: 0.23; 95% CI: 0.09, 0.60) magnesium. The linear inverse relation with SCD was strongest for plasma magnesium (P for trend = 0.003), in which each 0.25-mg/dL (1 SD) increment in plasma magnesium was associated with a 41% (95% CI: 15, 58%) lower risk of SCD. 

Conclusions: In this prospective cohort of women, higher plasma concentrations and dietary magnesium intakes were associated with lower risks of SCD. If the observed association is causal, interventions directed at increasing dietary or plasma magnesium might lower the risk of SCD. 

#3 

Carbohydrate metabolism and diabetes 

Dietary magnesium and fiber intakes and inflammatory and metabolic indicators in middle-aged subjects from a population-based cohort 

American Journal of Clinical Nutrition 2006 84: 1062-1069 

Simona Bo, Marilena Durazzo, Sabrina Guidi, Monica Carello, 

Carlotta Sacerdote, Barbara Silli, Rosalba Rosato, Maurizio Cassader, 

Luigi Gentile, and Gianfranco Pagano 

Dietary magnesium and fiber intakes and inflammatory and metabolic indicators in middle-aged subjects from a population-based cohort1,2,3 

Simona Bo, Marilena Durazzo, Sabrina Guidi, Monica Carello, Carlotta Sacerdote, Barbara Silli, Rosalba Rosato, Maurizio Cassader, Luigi Gentile and Gianfranco Pagano

Background Type 2 diabetes (DM), metabolic syndrome (MetS), and inflammation are linked to reduced magnesium and fiber intakes; these associations are attenuated by adjustment for each of these nutrients. 

Objective: We investigated the association among magnesium and fiber intakes, metabolic variables, and high-sensitivity C-reactive protein (hs-CRP) values. 

Design Cross-sectional analyses were performed in a representative cohort of 1653 adults and in a subgroup with normal body mass index without dysmetabolisms (n = 205). A validated semiquantitative food-frequency questionnaire was used; magnesium intake was computed by multiplying its content in each food by the frequency of food consumption. 

Results The prevalence of DM, MetS, and hs-CRP ≥ 3 mg/L significantly decreased from the lowest to the highest tertile of magnesium and fiber intakes. Subjects within the lowest tertiles of magnesium and fiber intakes were 3–4 times as likely to have DM, MetS, and hs-CRP ≥ 3 mg/L, after multiple adjustments. After the analysis was additionally controlled for fiber intake, associations with hs-CRP ≥ 3 mg/L proved to be significant (odds ratio: 2.05; 95% CI: 1.30, 3.25), whereas reduced magnesium intake and DM and MetS were no longer significant. The lowest tertile of fiber intake remained associated with DM, hs-CRP ≥ 3 mg/L, and MetS after adjustments for multiple confounders and magnesium intake. In the lean, healthy subject subgroup, hs-CRP values were inversely associated with magnesium and fiber intakes in a multivariate model (P < 0.001). 

Conclusions Reduced fiber intake was significantly associated with metabolic abnormalities; the magnesium effect might be confounded by fiber being in foods that also provided magnesium. Lower magnesium and fiber intakes were linked to hs-CRP ≥ 3 mg/L in both the entire cohort and healthy persons. 

#4 

Relations of dietary magnesium intake to biomarkers of inflammation and endothelial dysfunction in an ethnically diverse cohort of postmenopausal women

Diabetes Care 2010 Feb;33(2):304-10 

Chacko SA, Song Y, Nathan L, Tinker L, de Boer IH, Tylavsky F, Wallace R, Liu S.

Department of Epidemiology and Program on Genomics and Nutrition, School of Public Health, and Center for Metabolic Diseases Prevention, UCLA, Los Angeles, California 

Abstract 

OBJECTIVE: Although magnesium may favorably affect metabolic outcomes, few studies have investigated the role of magnesium intake in systemic inflammation and endothelial dysfunction in humans. 

RESEARCH DESIGN AND METHODS: Among 3,713 postmenopausal women aged 50-79 years in the Women's Health Initiative Observational Study and free of cardiovascular disease, cancer, and diabetes at baseline, we measured plasma concentrations of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), turnor necrosis factor-alpha receptor 2 (TNF-alpha-R2), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and E-selectin. Magnesium intake was assessed using a semiquantitative food frequency questionnaire. 

RESULTS: After adjustment for age, ethnicity, clinical center, time of blood draw, smoking, alcohol, physical activity, energy intake, BMI, and diabetes status, magnesium intake was inversely associated with hs-CRP (P for linear trend = 0.003), IL-6 (P < 0.0001), TNF-alpha-R2 (P = 0.0006), and sVCAM-1 (P = 0.06). Similar findings remained after further adjustment for dietary fiber, fruit, vegetables, folate, and saturated and trans fat intake. Multivariable-adjusted geometric means across increasing quintiles of magnesium intake were 3.08, 2.63, 2.31, 2.53, and 2.16 mg/l for hs-CRP (P = 0.005); 2.91, 2.63, 2.45, 2.27, and 2.26 pg/ml for IL-6 (P = 0.0005); and 707, 681, 673, 671, and 656 ng/ml for sVCAM-1 (P = 0.04). An increase of 100 mg/day magnesium was inversely associated with hs-CRP (-0.23 mg/l +/- 0.07; P = 0.002), IL-6 (-0.14 +/- 0.05 pg/ml; P = 0.004), TNF-alpha-R2 (-0.04 +/- 0.02 pg/ml; P = 0.06), and sVCAM-1 (-0.04 +/- 0.02 ng/ml; P = 0.07). No significant ethnic differences were observed. 

CONCLUSIONS: High magnesium intake is associated with lower concentrations of certain markers of systemic inflammation and endothelial dysfunction in postmenopausal women.