Magnesium in drinking water in relation to morbidity and mortality from acute myocardial infarction

Gut microbiota and cognitive development in infant mice: Quantity and source of potable water

Not only the water quantity consumed but also the source of drinking water has been considered for their health benefits, but there is limited evidence. We aimed to determine whether the amount and type of drinking water affect physiological and biological functions, including brain function, by confirming how it affects gut microbiota which has an important regulatory role in host physiology. Three-week-old infant mice were subjected to 1) a water restriction experiment (control group, ad libitum consumption of distilled water; dehydration group, time-limited access to distilled water [15 min/day]) and 2) different water source experiment (distilled water, purified water, spring water, and tap water groups). The gut microbiota and cognitive development were analyzed using the 16S ribosomal ribonucleic acid sequencing method and the Barnes maze, respectively. The relative abundance of Firmicutes and Bacteroidetes and the Firmicutes-to-Bacteroidetes ratio (F/B ratio) changed depending on age (juveniles vs. infants). Insufficient water intake reversed these developmental changes, showing that the relative abundances of Bacteroidetes and Firmicutes and the F/B ratio in dehydrated juvenile mice were similar to those in normal infant mice. Additionally, clustering analysis revealed no significant differences in the intestinal flora in the mice from the different drinking water sources; however, dehydration significantly altered the composition of the genera compared to the other water source groups wherein water was provided ad libitum. Moreover, cognitive development was significantly disrupted by insufficient water intake, although the type of drinking water had no significant influence. Cognitive decline, measured by relative latency, was positively associated with the relative abundance of unclassified Erysipelotrichaceae that were in significantly high relative abundance in the dehydration group. These results suggest that the water quantity consumed, rather than the mineral content of drinking water, is imperative for shaping the early gut microbiota associated with cognitive development during infancy.

High manganese and nickel concentrations in human hair and well water and low calcium concentration in blood serum in a pristine area with sulphide-rich bedrock

We report the trace element status of residents living in areas with naturally sulphide-rich bedrock and soil in two municipalities in Finland, Sotkamo and Kaavi. Altogether, 225 people from these sparsely populated regions participated voluntarily by providing hair and blood samples. The concentrations of calcium, zinc and copper in serum as well as selenium and cadmium in whole blood did not show correlation with those concentrations in hair samples. Calcium concentration in serum was slightly lower in the sulphide-rich areas (median value 91.4 mg/l, n = 103) than in the areas with adjacent sulphur-poor bedrock (median value 93.6 mg/l, n = 82). The concentrations of Ni and Mn in hair correlated with those in drinking water. The highest Mn and Ni concentrations in the water samples from private wells were 1620 µg/l and 51 µg/l and the highest concentrations in human hair samples 36.44 mg/kg and 12.3 mg/kg, respectively. The challenge with elevated trace element concentrations in some well waters is well documented. In northern countries (Finland, Sweden, Norway and Canada), only 10% of the population depend on private well water, and 90% have access to monitored municipal water supplies. Compared with data available from sulphide mine sites globally, the nickel and manganese concentrations in human hair samples were high in our sulphide-rich study area at Sotkamo representing the trace element status of residents under natural conditions.

Associations of alkaline water with metabolic risks, sleep quality, muscle strength: A cross-sectional study among postmenopausal women

Much has been claimed on the health benefits of alkaline water including metabolic syndrome (MetS) and its features with scarcity of scientific evidence. Methods: This cross-sectional comparative study was conducted to determine whether regular consumption of alkaline water confers health advantage on blood metabolites, anthropometric measures, sleep quality and muscle strength among postmenopausal women. A total of 304 community-dwelling postmenopausal women were recruited with comparable proportion of regular drinkers of alkaline water and non-drinkers. Participants were ascertained on dietary intake, lifestyle factors, anthropometric and biochemical measurements. Diagnosis of MetS was made according to Joint Interim Statement definition. A total of 47.7% of the participants met MS criteria, with a significant lower proportion of MetS among the alkaline water drinkers. The observed lower fasting plasma glucose (F(1,294) = 24.20, p = 0.025, partial η2 = 0.435), triglyceride/high-density lipoprotein concentration ratio (F(1,294) = 21.06, p = 0.023, partial η2 = 0.360), diastolic blood pressure (F(1,294) = 7.85, p = 0.046, partial η2 = 0.258) and waist circumference (F(1,294) = 9.261, p = 0.038, partial η2 = 0.263) in the alkaline water drinkers could be considered as favourable outcomes of regular consumption of alkaline water. In addition, water alkalization improved duration of sleep (F(1,294) = 32.05, p = 0.007, partial η2 = 0.451) and handgrip strength F(1,294) = 27.51, p = 0.011, partial η2 = 0.448). Low density lipoprotein cholesterol concentration (F(1,294) = 1.772, p = 0.287, partial η2 = 0.014), body weight (F(1,294) = 1.985, p = 0.145, partial η2 = 0.013) and systolic blood pressure (F(1,294) = 1.656, p = 0.301, partial η2 = 0.010) were comparable between the two different water drinking behaviours. In conclusion, drinking adequate of water is paramount for public health with access to good quality drinking water remains a critical issue. While consumption of alkaline water may be considered as a source of easy-to implement lifestyle to modulate metabolic features, sleep duration and muscle strength, further studies are warranted for unravelling the precise mechanism of alkaline water consumption on the improvement and prevention of MetS and its individual features, muscle strength and sleep duration as well as identification of full spectrum of individuals that could benefit from its consumption.

Calcium and magnesium in drinking water and risk of myocardial infarction and stroke-a population-based cohort study

BACKGROUND

The implication of calcium and magnesium in drinking water for cardiovascular disease is unclear.

OBJECTIVES

To assess the association of the concentration of calcium and magnesium in drinking water with incidence of myocardial infarction and stroke, accounting for dietary mineral intake.

METHODS

We linked drinking water monitoring data to residential information of 26,733 women from the population-based Swedish Mammography Cohort, who completed a 96-item FFQ at baseline. Drinking water was categorized into low (magnesium <10 mg/L and calcium <50 mg/L) or high (magnesium ≥10 mg/L or calcium ≥50 mg/L) mineral concentration. Incident cases of myocardial infarction and stroke types were ascertained 1998-2019 using the National Patient Register.

RESULTS

The mean ± SD concentration of calcium and magnesium in drinking water was 29 ± 7 mg/L and 5 ± 1 mg/L in the low-exposed area and 52 ± 20 mg/L and 10 ± 3 mg/L in the high-exposed area, respectively. During 16 years of follow-up, we ascertained 2023, 2279, and 452 cases of myocardial infarction, ischemic stroke, and hemorrhagic stroke, respectively. High drinking water calcium and magnesium was associated with lower risk of ischemic and hemorrhagic stroke HRs of 0.87 (95% CI: 0.80, 0.95) and 0.78 (95% CI: 0.65, 0.95), whereas the HR for myocardial infarction was 0.93 (95% CI: 0.85, 1.02). In separate analyses, only drinking water magnesium, not calcium, remained associated with ischemic stroke (HR: 0.69; 95% CI: 0.54, 0.88).

CONCLUSIONS

Drinking water with a high concentration of calcium and magnesium, particularly magnesium, may lower the risk of stroke in postmenopausal women.

Associations of Boiled Water and Lifespan Water Sources With Mortality: A Cohort Study of 33,467 Older Adults

Background:

There were few studies to report whether drinking water sources and habits affected health outcomes. Therefore, this study aimed to examine how boiled water and lifespan water sources affected the risks of cardiovascular disease (CVD) and all-cause mortality in the elderly.

Methods

This study was a 20-year cohort study. All participants aged ≥60 years were eligible. Exposures of interest included lifespan drinking water sources and habits, which were collected using a validated questionnaire. Drinking water sources included wells, surface water, spring, and tap water in childhood, around the age of 60 years, and at present. Drinking habits included boiled and un-boiled water. The main end events included CVD and all-cause mortality.

Results

There were 33,467 participants in this study. Compared to tap water, drinking well and surface water around the age of 60 years were associated with a higher risk of all-cause mortality (HR: 1.092, 95% CI: 1.051–1.134, P < 0.001; and HR: 1.136, 95% CI: 1.081–1.194, P < 0.001, respectively). However, only drinking spring around aged 60 years and drinking well at present were associated with a lower CVD mortality (HR: 0.651, 95% CI: 0.452–0.939, P = 0.022; and HR: 0.757, 95% CI: 0.665–0.863, P < 0.001, respectively). Boiled water was not associated with mortality.

Conclusions

Drinking water from well and surface water around the age of 60 years were associated with increased all-cause mortality. Drinking water from spring around the age of 60 years and well at present was associated with a decreased CVD mortality. However, boiled water was not associated with mortality.

Drinking water magnesium and cardiovascular mortality: A cohort study in Denmark, 2005-2016

INTRODUCTION

Cardiovascular diseases are globally a major cause of death. Magnesium deficiency is associated with several diseases including cardiovascular diseases.

OBJECTIVE

To examine if a low concentration of magnesium in drinking water is associated with increased cardiovascular mortality and mortality due to acute myocardial infarction and stroke.

METHODS

A nationwide population-based cohort study using national health registries was used. A total of 4,274,132 individuals aged 30 years or more were included. Magnesium concentration in drinking water was estimated by linkage of residential addresses in the period 2005-2016 with the national drinking water quality monitoring database. The association between magnesium concentration in drinking water and cardiovascular mortality and mortality due to acute myocardial infarction and stroke was examined using a Poisson regression of number of deaths and logarithmic transformation of follow-up time as offset. The incidence rate ratio (IRR) was adjusted for differences in age, sex, calendar year, cohabitation, country of origin, and socioeconomic status.

RESULTS

Median magnesium concentration in drinking water at inclusion was 12.4 mg/L (range: 1.37-54.2 mg/L). The adjusted IRR for cardiovascular mortality was 0.96 (95% CI: 0.94; 0.97) for the lowest magnesium quintile (<6.5 mg/L) as compared to the highest magnesium quintile (>21.9 mg/L). The adjusted IRR for mortality due to acute myocardial infarction and stroke was 1.22 (1.17; 1.27) and 0.96 (0.93; 0.99), respectively, for the lowest magnesium quintile as compared to the highest quintile A decreasing mortality due to acute myocardial infarction was seen with an increasing magnesium concentration in a dose-response manner.

CONCLUSION

Low concentrations of magnesium in drinking water were associated with an increased mortality due to acute myocardial infarction. Low concentrations of magnesium in drinking water were associated with decreased cardiovascular mortality, and mortality due to stroke.

Association between magnesium in drinking water and atrial fibrillation incidence: a nationwide population-based cohort study, 2002-2015

BACKGROUND

Atrial fibrillation (AF) is a common heart rhythm disorder and a risk factor of adverse cardiovascular diseases. Established causes do not fully explain the risk of AF and unexplained risk factors might be related to the environment, e.g. magnesium in drinking water. Low magnesium levels in drinking water might be associated with higher risk of cardiovascular diseases including AF. With detailed individual data from nationwide registries and long-term magnesium exposure time series, we had a unique opportunity to investigate the association between magnesium in drinking water and AF.

OBJECTIVE

We evaluated the association between magnesium concentration in drinking water and AF risk.

METHODS

A nationwide register-based cohort study (2002-2015) was used including individuals aged ≥30 years. Addresses were linked with water supply areas (n = 2418) to obtain time-varying drinking water magnesium exposure at each address. Five exposure groups were defined based on a 5-year rolling time-weighted average magnesium concentration. AF incidence rate ratios (IRRs) between exposure groups were calculated using a Poisson regression of incidence rates, adjusted for sex, age, and socioeconomic position. Robustness of results was investigated with different exposure definitions.

RESULTS

The study included 4,264,809 individuals (44,731,694 person-years) whereof 222,998 experienced an incident AF. Magnesium exposure ranged from 0.5 to 62.0 mg/L (mean = 13.9 mg/L). Estimated IRR (95% CI) compared to the referent exposure group (< 5 mg/L) was 0.98 (0.97-1.00) for the second lowest exposure group (5-10 mg/L), and 1.07 (1.05-1.08) for the two highest exposure groups (15-62 mg/L). Strongest positive associations were observed among those aged ≥80 years and with lowest education group. An inverse association was found among individuals with highest education group.

CONCLUSION

There might be a small beneficial effect on AF of an increase in magnesium level in drinking water up to 10 mg/L, though an overall positive association was observed. The unexpected positive association and different associations observed for subgroups suggest a potential influence of unaccounted factors, particularly in vulnerable populations. Future research on magnesium in drinking water and cardiovascular diseases needs to focus on contextual risk factors, especially those potentially correlating with magnesium in drinking water.

PROOXIDANT ACTIVITIES OF ANTIOXIDANTS AND THEIR IMPACT ON HEALTH

This review article is focused on the impact of antioxidants and prooxidants on health with emphasis on the type of antioxidants that should be taken. Medical researchers suggest that diet may be the solution for the control of chronic diseases such as cardiovascular complications, hypertension, diabetes mellitus, and different cancers. In this survey, we found scientific evidence that the use of antioxidants should be limited only to the cases where oxidative stress has been identified. This is often the case of specific population groups such as postmenopausal women, the elderly, infants, workers exposed to environmental pollutants, and the obese. Before starting any supplementation, it is necessary to measure oxidative stress and to identify and eliminate the possible sources of free radicals and thus increased oxidative stress.

Ecological analysis of associations between groundwater quality and hypertension and cardiovascular disease in rural Saskatchewan, Canada using Bayesian hierarchical models and administrative health data

Associations between groundwater quality and the prevalence of hypertension and ischemic heart disease were investigated in rural areas of the Canadian province of Saskatchewan. The partially ecological study was analyzed using Bayesian hierarchical models to account for spatial variability in risk. Exposure measures and health outcomes were estimated based on previously collected water quality surveillance data from public water supplies and private wells and administrative health data. Water quality exposures for each study region were estimated by applying geostatistical techniques to arsenic concentrations and principal component (PC) scores. The PC scores summarized groups of parameters measuring either health standards or aesthetic objectives described by the province. Generalized linear mixed models with a log link assessed associations between water quality and observed count of health outcomes relative to the expected value. The Bayesian models contained uncorrelated and spatially correlated random effects for each geographic region. Effect estimates were controlled for sex and age by stratification of case and expected case counts, for smoking by inclusion of sex- and age-specific prevalence of chronic obstructive pulmonary disease as a surrogate covariate, and for education and income by use of census data. There was no evidence for associations between groundwater arsenic concentrations in public or private water supplies and increased risk of hypertension or cardiovascular disease. An increase in the second aesthetic objectives PC score from public supplies was associated with a protective effect against ischemic heart disease. This PC value summarized hardness and magnesium Similarly, an increase in the second aesthetic objectives PC in private supplies was associated with decreased prevalence of hypertension. The results of this study are consistent with others demonstrating a relationship between elevated hardness and magnesium concentrations in drinking water and reduced risk of hypertension and cardiovascular disease. Further investigation is warranted with individual exposure history, particularly with respect to the potential beneficial effect of hard water on the prevalence of hypertension and cardiovascular disease.

Association between intraoperative magnesium sulfate infusion and mortality after non-cardiac surgery: a retrospective propensity score matched analysis

The short-term effects of magnesium sulfate infusion during surgery are well known. However, the long-term outcomes of intraoperative magnesium sulfate infusion remain unknown. Medical records of patients aged ≥20 years who underwent non-cardiac surgical procedures at Seoul National University Bundang Hospital between January, 2010 and October, 2016 were analyzed. After propensity score matching, 12,652 patients were included in the final analysis, 6326 each in the magnesium and non-magnesium groups. There were no significant differences in 30-day or 1-year mortality between subjects [30-day mortality, hazard ratio (HR): 1.31, 95% CI: 0.64-2.69, P = 0.465; 1-year mortality, HR: 1.20, 95%CI: 0.94-1.53, P = 0.136]. Intraoperative magnesium sulfate infusion was not significantly associated with postoperative 30-day or 1-year mortality.

Association between exposure to desalinated sea water and ischemic heart disease, diabetes mellitus and colorectal cancer; A population-based study in Israel

BACKGROUND

Drinking water (DW) is an important dietary source of magnesium. Recently, Israel has increased its use of desalinated seawater (DSW) as DW country-wide. Its negligible magnesium content, however, raises concern that consumption of DSW may be associated with hypomagnesemia and increase the risk of ischemic heart disease (IHD), diabetes mellitus (DM), and colorectal cancer (CRC).

OBJECTIVES

We tested whether there was a change in incidence of negative health outcomes (IHD, DM, and CRC) following the introduction of DSW supply in a population-based ecologic study in Israel.

METHODS

A historical prospective analysis was applied to members aged 25-76 during 2004-2013 of Clalit Health Services (Clalit), the largest healthcare provider in Israel, using its electronic medical record database. Multivariable analyses were adjusted for age, sex, socioeconomic status, smoking status, and body mass index.

RESULTS

An increased odds ratio was found for IHD (0.96, 95% CI 0.93-0.99 at baseline and 1.06, 95% CI 1.02-1.11 at the end of the follow-up period), but no time trend was observed.

CONCLUSIONS

We found that the risk for IHD increased during the study period. The risks for DM and CRC were unchanged. Long term studies are needed for assessing the risk for CRC due to the long latency. The higher risk for IHD has practical public health implications and raise the need to add magnesium to DSW.

Magnesium and Human Health: Perspectives and Research Directions

Magnesium is the fourth most abundant cation in the body. It has several functions in the human body including its role as a cofactor for more than 300 enzymatic reactions. Several studies have shown that hypomagnesemia is a common electrolyte derangement in clinical setting especially in patients admitted to intensive care unit where it has been found to be associated with increase mortality and hospital stay. Hypomagnesemia can be caused by a wide range of inherited and acquired diseases. It can also be a side effect of several medications. Many studies have reported that reduced levels of magnesium are associated with a wide range of chronic diseases. Magnesium can play important therapeutic and preventive role in several conditions such as diabetes, osteoporosis, bronchial asthma, preeclampsia, migraine, and cardiovascular diseases. This review is aimed at comprehensively collating the current available published evidence and clinical correlates of magnesium disorders.

Cardiovascular diseases and hard drinking waters: implications from a systematic review with meta-analysis of case-control studies

This systematic review with meta-analysis, performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, aims at evaluating the potential correlation between magnesium and calcium concentration in drinking waters and the risk of cardiovascular diseases (CVD), which impose a considerable burden in high-income countries. Included studies were of the case-control studies type. From an initial list of 643 potentially eligible articles, seven studies were finally retained in the quantitative analysis. Since each one of them assessed different ion concentrations, subjects exposed to the highest concentration versus those exposed to the lowest concentration were compared. By including an overall figure of 44,000 subjects, the result suggests a protective effect of the ions on CVD prevention, with an effect-size (ES) of 0.82 (95% confidence interval CI = [0.70-0.95], p-value = 0.008) for calcium, and ES = 0.75 (95% CI = [0.66-0.86], p-value = 0.000) for magnesium. Hard water consumption seems to be protective against CVD. However, the high heterogeneity (I² = 75.24, p-value = 0.001 for calcium; I² = 72.96, p-value = 0.0024 for magnesium) and the existence of publication bias limits the robustness and generalizability of these findings. Further high-quality studies are needed to reproduce and confirm these results.

Review of epidemiological studies on drinking water hardness and cardiovascular diseases

BACKGROUND

Major risk factors do not entirely explain the worldwide variability of morbidity and mortality due to cardiovascular disease. Environmental exposures, including drinking water minerals may affect cardiovascular disease risks.

METHOD

We conducted a qualitative review of the epidemiological studies of cardiovascular disease and drinking water hardness and calcium and magnesium levels.

RESULTS

Many but not all ecological studies found an inverse (i.e., protective) association between cardiovascular disease mortality and water hardness, calcium, or magnesium levels; but results are not consistent. Some case-control studies and one cohort study found either a reduced cardiovascular disease mortality risk with increased drinking water magnesium levels or an increased risk with low magnesium levels. However, the analytical studies provide little evidence that cardiovascular risks are associated with drinking water hardness or calcium levels.

CONCLUSION

Information from epidemiological and other studies supports the hypothesis that a low intake of magnesium may increase the risk of dying from, and possibly developing, cardiovascular disease or stroke. Thus, not removing magnesium from drinking water, or in certain situations increasing the magnesium intake from water, may be beneficial, especially for populations with an insufficient dietary intake of the mineral.

Natural fluoride in drinking water and myocardial infarction: A cohort study in Sweden

Large geographical variation in the coronary heart disease (CHD) incidence is seen worldwide and only a part of this difference is attributed to the classic risk factors. Several environmental factors, such as trace elements in the drinking water have been implicated in the pathogenesis of CHD. The objective was to assess the association between drinking water fluoride exposure and myocardial infarction in Sweden using nationwide registers. This large cohort consisted of 455,619 individuals, born in Sweden between January 1, 1900 and December 31, 1919, alive and living in their municipality of birth at the time of start of follow-up. Estimated individual drinking water fluoride exposure was stratified into four categories: very low (<0.3mg/l), low (0.3-<0.7mg/l), medium (0.7-<1.5mg/l) and high (≥1.5mg/l). In Cox regression analyses, compared to the very low fluoride group, the adjusted Hazard Ratio for the low fluoride group was 0.99 (95% confidence interval, 0.98-1.00), for the medium fluoride group 1.01 (95% confidence interval, 0.99-1.03) and 0.98 (95% confidence interval, 0.96-1.01) for the highest fluoride group. Adding water hardness to the model did not change the results. We conclude that the investigated levels of natural drinking water fluoride content does not appear to be associated with myocardial infarction, nor related to the geographic myocardial infarction risk variation in Sweden. Potential misclassification of exposure and unmeasured confounding may have influenced the results.

Desalinated seawater supply and all-cause mortality in hospitalized acute myocardial infarction patients from the Acute Coronary Syndrome Israeli Survey 2002-2013

BACKGROUND

Consuming desalinated seawater (DSW) as drinking water (DW) may reduce magnesium in water intake causing hypomagnesemia and adverse cardiovascular effects.

METHODS

We evaluated 30-day and 1-year all-cause mortality of acute myocardial infarction (AMI) patients enrolled in the biannual Acute Coronary Syndrome Israeli Survey (ACSIS) during 2002-2013. Patients (n=4678) were divided into 2 groups: those living in regions supplied by DSW (n=1600, 34.2%) and non-DSW (n=3078, 65.8%). Data were compared between an early period [2002-2006 surveys (n=2531) - before desalination] and a late period [2008-2013 surveys (n=2147) - during desalination].

RESULTS

Thirty-day all-cause-mortality was significantly higher in the late period in patients from the DSW regions compared with those from the non-DSW regions (HR=2.35 CI 95% 1.33-4.15, P<0.001) while in the early period there was no significant difference (HR=1.37 CI 95% 0.9-2, P=0.14). Likewise, there was a significantly higher 1-year all-cause mortality in the late period in patients from DSW regions compared with those from the non-DSW regions (HR=1.87 CI 95% 1.32-2.63, P<0.0001), while in the early period there was no significant difference (HR=1.17 CI 95% 0.9-1.5, P=0.22). Admission serum magnesium level (M±SD) in the DSW regions (n=130) was 1.94±0.24mg/dL compared with 2.08±0.27mg/dL in 81 patients in the non-DSW (P<0.0001).

CONCLUSIONS

Higher 30-day and 1-year all-cause mortality in AMI patients, found in the DSW regions may be attributed to reduced magnesium intake secondary to DSW consumption.

Magnesium Levels in Drinking Water and Coronary Heart Disease Mortality Risk: A Meta-Analysis

Epidemiological studies have demonstrated inconsistent associations between drinking water magnesium levels and risk of mortality from coronary heart disease (CHD); thus, a meta-analysis was performed to assess the association between them. Relevant studies were searched by the databases of Cochrane, EMBASE, PubMed and Web of Knowledge. Pooled relative risks (RR) with their 95% CI were calculated to assess this association using a random-effects model. Finally, nine articles with 10 studies involving 77,821 CHD cases were used in this study. Our results revealed an inverse association between drinking water magnesium level and CHD mortality (RR = 0.89, 95% CI = 0.79-0.99, I² = 70.6). Nine of the 10 studies came from Europe, and the association was significant between drinking water magnesium level and the risk of CHD mortality (RR = 0.83, 95% CI = 0.69-0.98). In conclusion, drinking water magnesium level was significantly inversely associated with CHD mortality.

[Very low magnesium levels in red blood cells as a significant factor in the etiopathogenesis of borderline disorders]

AIM

Basic studies indicate magnesium deficiency as one of the important, but often neglected, risk factors aggravating the course of borderline disorders (BD). A clinical verification of this notion has been conducted.

MATERIAL AND METHODS

Authors studied 62 patients with BD, aged 25-65 years, of inpatient and outpatient settings. Contents of magnesium and other blood electrolytes were determined.

RESULTS

Authors found an extremely high prevalence of very low levels of magnesium (Mg) in erythrocytes (<0.3 mmol/l) in patients with BD compared to controls (patients without BD, Mg (er.) 1.62±0.48 mmol/l). It has been shown that low Mg levels in the plasma and red blood cells are associated with a significantly increased risk of the following diagnoses: F07 «Personality and behavioral disorder due to brain disease, damage and dysfunction» (p<0.0016), F21 «Schizotypal disorder» (p<0.0005) and F34 «Persistent mood [affective] disorders» (p<0.0001). The use of Magne B6 Forte (4 tablets/day, 30 days, then 2 tablets/day for 1 year) resulted in a significant increase in the Mg levels in the plasma and erythrocytes, the compensation of anxiety and depressive symptoms, improvement of sleep and general health of the patients, reduced consumption of antidepressants (by 30%).

CONCLUSION

Administration of the drugs based on organic salts of magnesium per os improves the condition of patients and reduces their need in pharmacotherapy.

The high heart health value of drinking-water magnesium

Universal drinking water and beverages containing moderate to high levels of magnesium (10–100 ppm) could potentially prevent 4.5 million heart disease and stroke deaths per year, worldwide. This potential is calculated with 2010 global mortality figures combined with a recent quantification of water-magnesium’s inverse association with heart disease and stroke mortality. The modern processed food diet, low in magnesium and spreading globally, makes this well-researched potential of drinking-water magnesium worth serious consideration, especially in areas where insufficient dietary intake of magnesium is prevalent.

A new perspective on metals and other contaminants in fluoridation chemicals

BACKGROUND

Fluoride additives contain metal contaminants that must be diluted to meet drinking water regulations. However, each raw additive batch supplied to water facilities does not come labeled with concentrations per contaminant. This omission distorts exposure profiles and the risks associated with accidents and routine use.

OBJECTIVES

This study provides an independent determination of the metal content of raw fluoride products.

METHODS

Metal concentrations were analyzed in three hydrofluorosilicic acid (HFS) and four sodium fluoride (NaF) samples using inductively coupled plasma-atomic emission spectrometry. Arsenic levels were confirmed using graphite furnace atomic absorption analysis.

RESULTS

Results show that metal content varies with batch, and all HFS samples contained arsenic (4·9-56·0 ppm) or arsenic in addition to lead (10·3 ppm). Two NaF samples contained barium (13·3-18·0 ppm) instead. All HFS (212-415 ppm) and NaF (3312-3630 ppm) additives contained a surprising amount of aluminum.

CONCLUSIONS

Such contaminant content creates a regulatory blind spot that jeopardizes any safe use of fluoride additives.

Development of an enzymatic assay for sphingomyelin with rapid and automatable performances: Analysis in healthy subjects and coronary heart disease patients

BACKGROUND

Sphingomyelin (SM) is an important choline group-containing phospholipid and is considered to be an independent risk factor for coronary heart disease.

METHODS

We have developed a specific enzymatic assay for SM measurement with rapid and automatable performances by using two-reagent system involving sphingomyelinase. We performed within-run and between-run precision, linearity test, detection limit, recovery test and interference to validate this assay. Then, we measured the serum SM concentration in 194 healthy subjects and 141 consecutive patients undergoing coronary angiography.

RESULTS

The within-run and between-run coefficients of variation for SM concentrations were 1.1-1.3% and 1.0-1.2%, respectively. Quantitative measurements to a lower limit of 30 μmol/L were shown to be possible. The recoveries of the exogenously added SM to the control samples were 98.7%-101.5%. No effect was observed after the addition of some interference materials. The mean ± SD of the serum SM concentration in the 194 healthy subjects was 553.3 ± 100.1 μmol/L. We found that the SM concentration was significantly higher among an acute coronary syndrome subjects than among the healthy subjects (P<0.01) and that the serum SM concentrations were significantly correlated with the serum magnesium concentration.

CONCLUSIONS

We have developed a rapid and automatable enzymatic assay for SM that enables the automatic measurement of choline-containing phospholipids. This assay may be useful for various types of biochemical and clinical research.

Increasing of drinking water quality at real water treatment plant by recarbonization process

According to the World Health Organization, chemical and microbial contaminants in drinking water will continue in the interest of suppliers of drinking water. The review establishment of new knowledge for drinking water including the potential benefits of the mineral content is necessary. The paper is focused on an assessment of the quality of water from surface source for drinking water preparation and quality of drinking water produced at the real plant. The lab-scale verification of water recarbonization with lime and carbon dioxide was chosen based on the results of full scale plant data analysis. Recarbonization tests were carried out with the raw water and the impact of recarbonization on coagulation process at different coagulant doses was studied. The results show that water recarbonization had adverse influence on the water treatment processes.

Short-term magnesium deficiency upregulates ceramide synthase in cardiovascular tissues and cells: cross-talk among cytokines, Mg2+, NF-κB, and de novo ceramide

The present study tested the hypotheses that 1) short-term dietary deficiency (MgD) of magnesium (21 days) would result in the upregulation of ceramide synthase (CS) in left ventricular (LV), right ventricular, atrial, and aortic smooth muscle, as well as induce a synthesis/release of select cytokines and chemokines into the LV and aortic smooth muscle and serum; 2) exposure of primary cultured vascular smooth muscle cells (VSMCs) to low extracellular Mg concentration would lead to the synthesis/release of select cytokines/chemokines, activation of N-SMase, and the de novo synthesis of ceramide; and 3) inhibition of CS by fumonisin B1 (FB1) or inhibition of neutral sphingomyelinase (N-SMase) by scyphostatin (SCY) in VSMCs exposed to low Mg would result in reductions in the levels of the cytokines/chemokines and lowered levels of ceramide concomitant with inhibition of NF-κB activation. The data indicated that short-term MgD (10% normal dietary intake) resulted in the upregulation of CS in ventricular, atrial, and aortic smooth muscles coupled to the synthesis/release of 12 different cytokines/chemokines, as well as activation of NF-κB in the LV and aortic smooth muscle and sera; even very low levels of water-borne Mg (e.g., 15 mg·l−1·day−1) either prevented or ameliorated the upregulation and synthesis of the cytokines/chemokines. Our experiments also showed that VSMCs exposed to low extracellular Mg resulted in the synthesis of 5 different cytokines and chemokines concomitant with synthesis/release of ceramide. However, inhibition of the synthesis and release of ceramide by either FB1 or SCY attenuated, markedly , the generation of ceramide, release of the cytokines/chemokines, and activation of NF-κB (as measured by activated p65 and cRel).

Nutritional deficiencies and phospholipid metabolism

Phospholipids are important components of the cell membranes of all living species. They contribute to the physicochemical properties of the membrane and thus influence the conformation and function of membrane-bound proteins, such as receptors, ion channels, and transporters and also influence cell function by serving as precursors for prostaglandins and other signaling molecules and modulating gene expression through the transcription activation. The components of the diet are determinant for cell functionality. In this review, the effects of macro and micronutrients deficiency on the quality, quantity and metabolism of different phospholipids and their distribution in cells of different organs is presented. Alterations in the amount of both saturated and polyunsaturated fatty acids, vitamins A, E and folate, and other micronutrients, such as zinc and magnesium, are discussed. In all cases we observe alterations in the pattern of phospholipids, the more affected ones being phosphatidylcholine, phosphatidylethanolamine and sphingomyelin. The deficiency of certain nutrients, such as essential fatty acids, fat-soluble vitamins and some metals may contribute to a variety of diseases that can be irreversible even after replacement with normal amount of the nutrients. Usually, the sequelae are more important when the deficiency is present at an early age.

Pediatric reference values for serum magnesium levels in Iranian subjects

Magnesium (Mg), an essential element, plays important roles in many physiological functions. Mg deficiency is associated with insulin resistance, cardiovascular disease, and disorders of the nervous system. The aim of this study was to determine reference values for serum Mg concentration in pediatrics. Serum Mg level was measured by flame atomic absorption spectrophotometry in 306 subjects (141 boys and 165 girls), aged 3-19 years, selected from among participants of the Tehran Lipid and Glucose Study. The International Federation of Clinical Chemistry guidelines (IFCC) and the robust method were used for determining reference values for sample sizes greater or less than 120 subjects respectively. The 95% reference values for serum Mg concentrations were 0.76-1.0, 0.75-1.0, and 0.76-0.99 mmol/L in boys, girls, and the all subjects respectively. According to the reference values obtained in this study, the prevalences of hypo- and hypermagnesemia, were 5.9% and 5.6% respectively. In conclusion, the current study presents pediatric reference values for serum Mg levels derived from a randomly selected healthy population, values which could be instrumental in detecting serum Mg abnormalities.

Short-term magnesium deficiency upregulates sphingomyelin synthase and p53 in cardiovascular tissues and cells: relevance to the de novo synthesis of ceramide

The present study tested the hypotheses that 1) short-term dietary deficiency of magnesium (21 days) in rats would result in the upregulation of sphingomyelin synthase (SMS) and p53 in cardiac and vascular (aortic) smooth muscles, 2) low levels of Mg(2+) added to drinking water would either prevent or greatly reduce the upregulation of both SMS and p53, 3) exposure of primary cultured vascular smooth muscle cells (VSMCs) to low extracellular Mg(2+) concentration ([Mg(2)](o)) would lead to the de novo synthesis of ceramide, 4) inhibition of either SMS or p53 in primary culture VSMCs exposed to low [Mg(2+)](o) would lead to reductions in the levels of de novo ceramide synthesis, and 5) inhibition of sphingomyelin palmitoyl-CoA transferase (SPT) or ceramide synthase (CS) in primary cultured VSMCs exposed to low [Mg(2+)](o) would lead to a reduction in the levels of de novo ceramide synthesis. The data indicated that short-term magnesium deficiency (10% normal dietary intake) resulted in the upregulation of SMS and p53 in both ventricular and aortic smooth muscles; even very low levels of water-borne Mg(2+) (e.g., 15 mg·l(-1)·day(-1)) either prevented or ameliorated the upregulation in SMS and p53. Our experiments also showed that VSMCs exposed to low [Mg(2+)](o) resulted in the de novo synthesis of ceramide; the lower the [Mg(2+)](o), the greater the synthesis of ceramide. In addition, the data indicated that inhibition of either SMS, p53, SPT, or CS in VSMCs exposed to low [Mg(2+)](o) resulted in marked reductions in the de novo synthesis of ceramide.

Reference values for serum magnesium levels in young adult Iranian subjects

This study aims at determining the reference values for serum magnesium (Mg) concentrations in Iranian adults. Serum Mg level was measured using flame atomic absorption spectrometry in 491 subjects (233 men and 258 women), aged 20-50 years, randomly selected from a population-based study. The International Federation of Clinical Chemistry guidelines and the robust method were used for determining the reference values. The 95% reference values for serum Mg concentration were 1.83-2.49, 1.79-2.48, and 1.83-2.55 mg/dL in men, women, and total population, respectively. The prevalences of hypo- and hypermagnesemia, according to the reference values obtained in the current study, were 2.5% and 4.0%, respectively. In conclusion, this study reports serum Mg reference values based on current standards in a large healthy population of young Iranian adults.

Acid-base balance and hydration status following consumption of mineral-based alkaline bottled water

Background

The present study sought to determine whether the consumption of a mineral-rich alkalizing (AK) bottled water could improve both acid-base balance and hydration status in young healthy adults under free-living conditions. The AK water contains a naturally high mineral content along with Alka-PlexLiquid™, a dissolved supplement that increases the mineral content and gives the water an alkalizing pH of 10.0.

Methods

Thirty-eight subjects were matched by gender and self-reported physical activity (SRPA, hrs/week) and then split into Control (12 women, 7 men; Mean +/- SD: 23 +/- 2 yrs; 7.2 +/- 3.6 hrs/week SRPA) and Experimental (13 women, 6 men; 22 +/- 2 yrs; 6.4 +/- 4.0 hrs/week SRPA) groups. The Control group consumed non-mineralized placebo bottled water over a 4-week period while the Experimental group consumed the placebo water during the 1st and 4th weeks and the AK water during the middle 2-week treatment period. Fingertip blood and 24-hour urine samples were collected three times each week for subsequent measures of blood and urine osmolality and pH, as well as total urine volume. Dependent variables were analyzed using multivariate repeated measures ANOVA with post-hoc focused on evaluating changes over time within Control and Experimental groups (alpha = 0.05).

Results

There were no significant changes in any of the dependent variables for the Control group. The Experimental group, however, showed significant increases in both the blood and urine pH (6.23 to 7.07 and 7.52 to 7.69, respectively), a decreased blood and increased urine osmolality, and a decreased urine output (2.51 to 2.05 L/day), all during the second week of the treatment period (P < 0.05). Further, these changes reversed for the Experimental group once subjects switched to the placebo water during the 4th week.

Conclusions

Consumption of AK water was associated with improved acid-base balance (i.e., an alkalization of the blood and urine) and hydration status when consumed under free-living conditions. In contrast, subjects who consumed the placebo bottled water showed no changes over the same period of time. These results indicate that the habitual consumption of AK water may be a valuable nutritional vector for influencing both acid-base balance and hydration status in healthy adults.

A double-blind, placebo-controlled study of the short term effects of a spring water supplemented with magnesium bicarbonate on acid/base balance, bone metabolism and cardiovascular risk factors in postmenopausal women

Background

A number of health benefits including improvements in acid/base balance, bone metabolism, and cardiovascular risk factors have been attributed to the intake of magnesium rich alkaline mineral water. This study was designed to investigate the effects of the regular consumption of magnesium bicarbonate supplemented spring water on pH, biochemical parameters of bone metabolism, lipid profile and blood pressure in postmenopausal women.

Findings

In this double-blind, placebo-controlled, parallel-group, study, 67 postmenopausal women were randomised to receive between 1500 mL and 1800 mL daily of magnesium bicarbonate supplemented spring water (650 mg/L bicarbonate, 120 mg/L magnesium, pH 8.3-8.5) (supplemented water group) or spring water without supplements (control water group) over 84 days. Over this period biomarkers of bone turnover (serum parathyroid hormone (PTH), 1,25-dihydroxyvitamin D, osteocalcin, urinary telopeptides and hydroxyproline), serum lipids (total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides), venous and urinary pH were measured together with measurements of standard biochemistry, haematology and urine examinations.

Serum magnesium concentrations and urinary pH in subjects consuming the magnesium bicarbonate supplemented water increased significantly at Day 84 compared to subjects consuming the spring water control (magnesium - p = 0.03; pH - p = 0.018). The consumption of spring water led to a trend for an increase in parathyroid hormone (PTH) concentrations while the PTH concentrations remained stable with the intake of the supplemented spring water. However there were no significant effects of magnesium bicarbonate supplementation in changes to biomarkers of bone mineral metabolism (n-telopeptides, hydroxyproline, osteocalcin and 1,25-dihydroxyvitamin D) or serum lipids or blood pressure in postmenopausal women from Day 0 to Day 84.

Conclusions

Short term regular ingestion of magnesium bicarbonate supplemented water provides a source of orally available magnesium. Long term clinical studies are required to investigate any health benefits.

Trial registration

ACTRN12609000863235

Magnesium deficiency upregulates serine palmitoyl transferase (SPT 1 and SPT 2) in cardiovascular tissues: relationship to serum ionized Mg and cytochrome c

The present work tested the hypothesis that a short-term dietary deficiency of magnesium (Mg) (21 days) in rats would result in the upregulation of the two major subunits of serine palmitoyl-CoA-transferase, serine palmitoyl transferase (SPT 1) and SPT 2 (the rate-limiting enzymes responsible for the de novo biosynthesis of ceramides) in left ventricular, right ventricular, and atrial heart muscle and abdominal aortic smooth muscle, as well as induce a reduction in serum sphingomyelin concomitant with the release of mitochondrial cytochrome c (Cyto c) in these tissues. Our data indicate that short-term Mg deficiency (MgD) resulted in an upregulation of SPT 1 and SPT 2, concomitant with a very significant release of Cyto c in left ventricular, right ventricular, atrial, and abdominal aortic smooth muscle. Short-term MgD also produced a lowering of serum sphingomyelin and ionized Mg. The greater the reduction in serum ionized Mg, the greater the upregulation of SPT 1 and 2 and the more the increase in free Cyto c. The data suggest that MgD, most likely, causes a biosynthesis of ceramides via two pathways in cardiovascular tissues, viz., via the activation of serine palmitoyl-CoA-transferase and sphingomyelinase, which lead to apoptotic events via intrinsic (present study) and extrinsic pathways (previous studies). Low levels of drinking water Mg were cardio- and vasculoprotective.

Relationship between tap water hardness, magnesium, and calcium concentration and mortality due to ischemic heart disease or stroke in The Netherlands

BACKGROUND

Conflicting results on the relationship between the hardness of drinking water and mortality related to ischemic heart disease (IHD) or stroke have been reported.

OBJECTIVES

We investigated the possible association between tap water calcium or magnesium concentration and total hardness and IHD mortality or stroke mortality.

METHODS

In 1986, a cohort of 120,852 men and women aged 5569 years provided detailed information on dietary and other lifestyle habits. Follow-up for mortality until 1996 was established by linking data from the Central Bureau of Genealogy and Statistics Netherlands. We calculated tap water hardness for each postal code using information obtained from all pumping stations in the Netherlands. Tap water hardness was categorized as soft [< 1.5 mmol/L calcium carbonate (CaCO3)], medium hard (1.62.0 mmol/L CaCO3), and hard (> 2.0 mmol/L CaCO3). The multivariate case-cohort analysis was based on 1,944 IHD mortality and 779 stroke mortality cases and 4,114 subcohort members.

RESULTS

For both men and women, we observed no relationship between tap water hardness and IHD mortality [hard vs. soft water: hazard ratio (HR) = 1.03; 95% confidence interval (CI), 0.851.28 for men and HR = 0.93; 95% CI, 0.711.21 for women) and stroke mortality (hard vs. soft water HR = 0.90; 95% CI, 0.661.21 and HR = 0.86; 95% CI, 0.621.20, respectively). For men with the 20% lowest dietary magnesium intake, an inverse association was observed between tap water magnesium intake and stroke mortality (HR per 1 mg/L intake = 0.75; 95% CI, 0.610.91), whereas for women with the 20% lowest dietary magnesium intake, the opposite was observed.

CONCLUSIONS

We found no evidence for an overall significant association between tap water hardness, magnesium or calcium concentrations, and IHD mortality or stroke mortality. More research is needed to investigate the effect of tap water magnesium on IHD mortality or stroke mortality in subjects with low dietary magnesium intake.

Short-term magnesium deficiency results in decreased levels of serum sphingomyelin, lipid peroxidation, and apoptosis in cardiovascular tissues

The present study tested the hypothesis that short-term dietary deficiency of magnesium (Mg) (21 days) in rats would 1) result in decreased serum(s) [the present study tested the levels of Mg, sphingomyelin (SM), and phosphatidylcholine (PC)]; 2) promote DNA fragmentation, lipid peroxidation (LP), and activation of caspase-3 in cardiac (ventricular and atrial) and vascular(aortic) muscle; and 3) low levels of Mg(2+) added to drinking water would either prevent or greatly ameliorate these manifestations. The data indicate that short-term Mg deficiency (10% normal dietary intake) resulted in profound reductions in serum-ionized Mg and total Mg with an elevation in serum-ionized calcium (Ca(2+)), significant lowering of serum SM and serum PC, with concomitant LP, DNA fragmentation, and activation of caspase-3 in ventricular (right and left chambers), atrial (right and left chambers) and abdominal aortic smooth muscle. The greater the reduction in serum-ionized Mg, the greater the effects on DNA fragmentation, LP, and caspase-3 activity. The intake of water-borne Mg(2+) at all levels greatly attenuated or inhibited the reductions in serum SM and serum PC, activation of LP, DNA fragmentation, and the activation of caspase-3; even very low levels of Mg(2+) in drinking water (i.e., 15 parts.million(-1).day(-1)) were cardio- and vascular protective. In addition, we demonstrate that short-term dietary deficiency of Mg probably results in a downregulation of SM synthase and a decreased synthesis of PC.

Drinking water constituents and disease

Several epidemiological investigations over the last 50 y have demonstrated a relation between risk for cardiovascular disease and drinking water hardness or its content of magnesium and calcium. An additional parameter, first suggested in a study from Japan 50 y ago, is the acidity of the water. It is known that acid load influences the reabsorption of calcium and magnesium in the renal tubuli. Intervention studies have shown that acid-base conditions influence the homeostasis of minerals. Data from intervention studies using magnesium, calcium, and hydrogen carbonate are reviewed. It is suggested that the health effects related to drinking water found in some studies may be caused by an increased urinary excretion of minerals induced by acid conditions in the body and that drinking water should contain sufficient amounts of hydrogen carbonate to prevent this effect.

Acid-base status affects renal magnesium losses in healthy, elderly persons

Magnesium and calcium deficiency in humans is related to a number of pathological phenomena such as arrhythmia, osteoporosis, migraine, and fatal myocardial infarction. Clinically established metabolic acidosis induces renal losses of calcium. In normal subjects, even moderate increases in net endogenous acid production (NEAP) impair renal calcium reabsorption but no information is available whether this also influences renal magnesium handling. The aim of the study was to examine the relation between NEAP and renal magnesium excretion in healthy, free-living, elderly subjects. The subjects (age 64 +/- 4.7 y, n = 85) were randomly selected from the population register in Gothenburg (Sweden). Magnesium, calcium, and potassium were measured in 24-h urine samples and NEAP was quantified as renal net acid excretion (NAE). NAE was positively correlated with excretions of magnesium (R(2) = 0.27, P < 0.0001) and calcium (R(2) = 0.30, P < 0.0001) but not potassium. When 24-h urinary magnesium excretion was adjusted for 24-h urinary potassium excretion, a biomarker for dietary potassium intake, the association between magnesium excretion and NAE remained significant (R(2) = 0.21, P < 0.0001). The significant association between potassium-adjusted magnesiuria and NAE suggests that the acid-base status affects renal magnesium losses, irrespectively of magnesium intake. Magnesium deficiency could thus, apart from an insufficient intake, partly be caused by the acid load in the body.

Calcium and magnesium in drinking water and risk of death from acute myocardial infarction in Taiwan

Many studies have examined the association between cardiovascular disease mortality and water hardness. However, the results have not been consistent. This report examines whether calcium and magnesium in drinking water are protective against acute myocardial infarction (AMI). All eligible AMI deaths (10,094 cases) of Taiwan residents from 1994 to 2003 were compared with deaths from other causes (10,094 controls), and the levels of calcium and magnesium in drinking water of these residents were determined. Data on calcium and magnesium levels in drinking water throughout Taiwan have been obtained from the Taiwan Water Supply Corporation. The control group consisted of people who died from other causes and the controls were pair matched to the cases by sex, year of birth, and year of death. The adjusted odd ratios (95% confidence interval) were 0.79 (0.73-0.86) for the group with water calcium levels between 25.1 and 42.4 mg/L and 0.71 (0.65-0.77) for the group with calcium levels of 42.6 mg/L or more. After adjustment for calcium levels in drinking water, there was no difference between the groups with different levels of magnesium. The results of the present study show that there is a significant protective effect of calcium intake from drinking water on the risk of death from AMI.

Concentrations of inorganic elements in 20 municipal waters in Sweden before and after treatment--links to human health

The water chemistry of 20 municipal water treatment plants in southern Sweden, representing various bedrock situations, and water qualities, were investigated. Four water samples, raw and treated, were collected from each plant and analyzed by predominantly ICP-OES and ICP-MS at four occasions from June to December, 2001. The concentrations of Ca, Mg, K, Na, HCO(3) and a number of micronutrients, varied considerably in treated waters from the studied plants (ranges; Ca: 9.1-53.7 mg L(-1), Mg: 1.4-10.9 mg L(-1), K: 1.1-4.8 mg L(-1), Na; 5.4-75.6 mg L(-1), HCO(3): 27-217 mg L(-1)). The elimination of Fe and Mn from raw water was efficient in all treatments investigated, giving concentrations in treated waters below the detection limits at some plants. Softening filters gave waters with Ca-concentrations comparable to the softest waters in this study. Adjustment of pH by use of chemicals like lye, soda or lime, modified the consumer water composition significantly, besides raising the pH. It was estimated that drinking water contributed to approximately 2.2-13% of the daily Ca uptake, if the gastrointestinal uptake efficiency from food and water was estimated to be around 50%. The corresponding figures for Mg was 1.0-7% and for F 0-59%. None of the studied elements showed any significant time trends in raw or treated waters during the follow-up period. The concentrations of potentially toxic metals such as Al, Pb and U were low and did not indicate risks for adverse health effects (ranges; Al: 0.5-2.3 microg L(-1), Pb: 0-0.3 microg L(-1), U: 0.2.5 microg L(-1)).

Calcium:magnesium ratio in local groundwater and incidence of acute myocardial infarction among males in rural Finland

Several epidemiologic studies have shown an association between calcium and magnesium and coronary heart disease mortality and morbidity. In this small-area study, we examined the relationship between acute myocardial infarction (AMI) risk and content of Ca, Mg, and chromium in local groundwater in Finnish rural areas using Bayesian modeling and geospatial data aggregated into 10 km times symbol 10 km grid cells. Data on 14,495 men 35-74 years of age with their first AMI in the years 1983, 1988, or 1993 were pooled. Geochemical data consisted of 4,300 measurements of each element in local groundwater. The median concentrations of Mg, Ca, and Cr and the Ca:Mg ratio in well water were 2.61 mg/L, 12.23 mg/L, 0.27 microg/L, and 5.39, respectively. Each 1 mg/L increment in Mg level decreased the AMI risk by 4.9%, whereas a one unit increment in the Ca:Mg ratio increased the risk by 3.1%. Ca and Cr did not show any statistically significant effect on the incidence and spatial variation of AMI. Results of this study with specific Bayesian statistical analysis support earlier findings of a protective role of Mg and low Ca:Mg ratio against coronary heart disease but do not support the earlier hypothesis of a protective role of Ca.

Concentrations of inorganic elements in bottled waters on the Swedish market

This study presents the concentrations of about 50 metals and ions in 33 different brands of bottled waters on the Swedish market. Ten of the brands showed calcium (Ca) concentrations </=10 mg L(-1) and magnesium (Mg) levels <3 mg L(-1), implying very soft waters. Three of these waters had in addition low concentrations of sodium (Na; <7 mg L(-1)), potassium (K; <3 mg L(-1)) and bicarbonate (HCO(3) </=31 mg L(-1)). These brands were collected from barren districts. Nine of the brands were collected from limestone regions. They showed increased Ca-levels exceeding 50 mg L(-1) with a maximum of 289 mg L(-1). Corresponding Mg-levels were also raised in two brands exceeding 90 mg L(-1). Two soft and carbonated waters were supplemented with Na(2)CO(3) and NaCl, resulting in high concentrations of Na (644 and 648 mg L(-1)) and chloride (Cl; 204 and 219 mg L(-1)). Such waters may make a substantial contribution to the daily intake of NaCl in high water consumers. The storage of carbonated drinking water in aluminum (Al) cans increased the Al-concentration to about 70 microg L(-1). Conclusion As there was a large variation in the material as regards concentrations of macro-elements such as Ca, Mg, Na, K and Cl. Supplementation with salts, e.g., Na(2)CO(3), K(2) CO(3) and NaCl, can lead to increased concentrations of Na, K and Cl, as well as decreased ratios of Ca/Na and larger ratios of Na/K. Water with high concentrations of e.g., Ca and Mg, may make a substantial contribution to the daily intake of these elements in high water consumers. Al cans are less suited for storage of carbonated waters, as the lowered pH-values may dissolve Al. The levels of potentially toxic metals in the studied brands were generally low.

Daily Intake of Magnesium and Calcium From Drinking Water in Relation to Myocardial Infarction

BACKGROUND

A decreased risk for cardiovascular disease has been related to the hardness of drinking water, particularly high levels of magnesium. However, the evidence is still uncertain, especially in relation to individual intake from water.

METHODS

We used data from the Stockholm Heart Epidemiology Program, a population-based case-control study conducted during 1992-1994, to study the association between myocardial infarction and the daily intake of drinking water magnesium and calcium. Our analyses are based on 497 cases age 45-70 years, and 677 controls matched on age, sex, and hospital catchment area. Individual data on magnesium, calcium, and hardness of the domestic drinking water were assessed from waterwork registers or analyses of well water.

RESULTS

After adjustment for the matching variables and smoking, hypertension, socioeconomic status, job strain, body mass index, diabetes, and physical inactivity, the odds ratio for myocardial infarction was 1.09 (95% confidence interval = 0.81-1.46) associated with a tap water hardness above the median (>4.4 German hardness degrees) and 0.88 (0.67-1.15) associated with a water magnesium intake above the median (>1.86 mg/d). There was no apparent sign of any exposure-response pattern related to water intake of magnesium or calcium.

CONCLUSIONS

This study does not support previous reports of a protective effect on myocardial infarction associated with consumption of drinking water with higher levels of hardness, magnesium, or calcium.

Mineral water intake reduces blood pressure among subjects with low urinary magnesium and calcium levels

Background

Several previous epidemiological studies have shown a relation between drinking water quality and death in cardiovascular disease whereas others have not found such a relationship. An intervention study was undertaken to evaluate the effect of water with added magnesium and natural mineral water on blood pressure.

Methods

A group of 70 subjects with borderline hypertension was recruited and consumed 1) a water low in minerals, 2) magnesium enriched water or 3) natural mineral water, in a random, double blind fashion during four weeks.

Results

Among persons with an initial low excretion of magnesium or calcium in the urine, the urinary excretion of magnesium was increased in the groups consuming the two waters containing magnesium after 4 weeks. A significant decrease in blood pressure was found in the group consuming mineral water at 2 and 4 weeks.

Conclusion

The results suggest that minerals taken in water are significant for the body burden and that an intake of mineral water among persons with a low urinary excretion of magnesium or calcium may decrease the blood pressure. Further studies should investigate the extent of mineral deficiency in different populations and the efficiency of different vehicles for supplying minerals, particularly magnesium and calcium.

Spatial analysis of the relationship between mortality from cardiovascular and cerebrovascular disease and drinking water hardness

Previously published scientific papers have reported a negative correlation between drinking water hardness and cardiovascular mortality. Some ecologic and case-control studies suggest the protective effect of calcium and magnesium concentration in drinking water. In this article we present an analysis of this protective relationship in 538 municipalities of Comunidad Valenciana (Spain) from 1991-1998. We used the Spanish version of the Rapid Inquiry Facility (RIF) developed under the European Environment and Health Information System (EUROHEIS) research project. The strategy of analysis used in our study conforms to the exploratory nature of the RIF that is used as a tool to obtain quick and flexible insight into epidemiologic surveillance problems. This article describes the use of the RIF to explore possible associations between disease indicators and environmental factors. We used exposure analysis to assess the effect of both protective factors--calcium and magnesium--on mortality from cerebrovascular (ICD-9 430-438) and ischemic heart (ICD-9 410-414) diseases. This study provides statistical evidence of the relationship between mortality from cardiovascular diseases and hardness of drinking water. This relationship is stronger in cerebrovascular disease than in ischemic heart disease, is more pronounced for women than for men, and is more apparent with magnesium than with calcium concentration levels. Nevertheless, the protective nature of these two factors is not clearly established. Our results suggest the possibility of protectiveness but cannot be claimed as conclusive. The weak effects of these covariates make it difficult to separate them from the influence of socioeconomic and environmental factors. We have also performed disease mapping of standardized mortality ratios to detect clusters of municipalities with high risk. Further standardization by levels of calcium and magnesium in drinking water shows changes in the maps when we remove the effect of these covariates.

Geochemistry of ground water and the incidence of acute myocardial infarction in Finland

STUDY OBJECTIVE

To examine the association of spatial variation in acute myocardial infarction (AMI) incidence and its putative environmental determinants in ground water such as total water hardness, the concentration of calcium, magnesium, fluoride, iron, copper, zinc, nitrate, and aluminium.

DESIGN

Small area study using Bayesian modelling and the geo-referenced data aggregated into 10 km x 10 km cells.

SETTING

The population data were obtained from Statistics Finland, AMI case data from the National Death Register and the Hospital Discharge Register, and the geochemical data from hydrogeochemical database of Geological Survey of Finland.

PARTICIPANTS

A total of 18 946 men aged 35-74 years with the first AMI attack in the years 1983, 1988, and 1993.

MAIN RESULTS

One unit (in German degree degrees dH) increment in water hardness decreased the risk of AMI by 1%. Geochemical elements in ground water included in this study did not show a statistically significant effect on the incidence and spatial variation of AMI, even though suggestive findings were detected for fluoride (protective), iron and copper (increasing).

CONCLUSIONS

The results of this study with more specific Bayesian statistical analysis confirm findings from earlier observations of the inverse relation between water hardness and coronary heart disease. The role of environmental geochemistry in the geographical variation of the AMI incidence should be studied further in more detail incorporating the individual intake of both food borne and water borne nutrients. Geochemical-spatial analysis provides a basis for the selection of areas suitable for such research.

Drinking water and cardiovascular disease

A link between cardiovascular disease (CVD) mortality and the hardness of drinking water (DW) is suggested by about 30 epidemiological studies performed worldwide in the general population since 1957. This review examines the main ecological studies, case-control studies and cohort studies, published between 1960 and 2000. Attention is paid to the problem of interpretation of this typical result of environmental epidemiology. Some studies focused on the role played by inorganic elements known as DW contaminants (mainly, As, Pb) and above all on the role of the magnesium content of DW and its cardioprotective effects. To date, it would be impossible to understand this environmental findings without large intervention studies performed in well-controlled public health programs.