Magnesium Matters for Your Heart
Magnesium may seem like a common mineral, but this one nutrient is vitally important. It provides energy for our cells, helps our muscles recover easily after heavy exercise, assists thyroid metabolism, and promotes clear thinking.
And if you think that you’re getting enough magnesium from food sources alone, you may be mistaken. Magnesium has been depleted in the soil and is often stripped from foods during processing, and it’s one of the most commonly lacking nutrients in the diet. In fact, some experts estimate that up to 80 percent of the U.S. population is deficient. This is alarming news when you consider that one of the most important jobs of magnesium is keeping the heart healthy and strong. Any lack of magnesium can have serious consequences.
For example, a large population-based study of over 9,000 participants in the Netherlands examined the link between magnesium levels, the risk of coronary heart disease (CHD), and cases of sudden cardiac death (SCD). They found that without enough magnesium, arteries thickened and the tone and overall health of blood vessels declined. A Finnish study found that because of magnesium’s essential relationship to cellular energy and heart rhythms, low levels are also a risk for heart failure in men – even after accounting for other factors like lifestyle, blood pressure, and weight.
But the good news is that it’s never too late to supplement, regardless of your age or weight. A randomized, double-blind, placebo-controlled clinical study published in the American Journal of Clinical Nutrition showed that after six months of supplementation, older adults who were overweight or obese had healthier, more flexible arteries. Ultimately, that meant better blood pressure and less strain on the heart.
Some individuals’ digestive systems can react strongly to common supplemental forms of magnesium. The best form of the mineral for optimum results and daily use is one that is easy on the stomach and easily absorbed and utilized. For that, a glycinate chelate form is the ideal choice.
Kieboom BC, Niemeijer MN, Leening MJ, van den Berg ME, et al. Serum Magnesium and the Risk of Death From Coronary Heart Disease and Sudden Cardiac Death. J Am Heart Assoc. 2016 Jan 22;5(1). pii: e002707.
BACKGROUND: Low serum magnesium has been implicated in cardiovascular mortality, but results are conflicting and the pathway is unclear. We studied the association of serum magnesium with coronary heart disease (CHD) mortality and sudden cardiac death (SCD) within the prospective population-based Rotterdam Study, with adjudicated end points and long-term follow-up.
METHODS AND RESULTS: Nine-thousand eight-hundred and twenty participants (mean age 65.1 years, 56.8% female) were included with a median follow-up of 8.7 years. We used multivariable Cox proportional hazard models and found that a 0.1 mmol/L increase in serum magnesium level was associated with a lower risk for CHD mortality (hazard ratio: 0.82, 95% CI 0.70-0.96). Furthermore, we divided serum magnesium in quartiles, with the second and third quartile combined as reference group (0.81-0.88 mmol/L). Low serum magnesium (≤0.80 mmol/L) was associated with an increased risk of CHD mortality (N=431, hazard ratio: 1.36, 95% CI 1.09-1.69) and SCD (N=217, hazard ratio: 1.54, 95% CI 1.12-2.11). Low serum magnesium was associated with accelerated subclinical atherosclerosis (expressed as increased carotid intima-media thickness: +0.013 mm, 95% CI 0.005-0.020) and increased QT-interval, mainly through an effect on heart rate (RR-interval: -7.1 ms, 95% CI -13.5 to -0.8). Additional adjustments for carotid intima-media thickness and heart rate did not change the associations with CHD mortality and SCD.
CONCLUSIONS: Low serum magnesium is associated with an increased risk of CHD mortality and SCD. Although low magnesium was associated with both carotid intima-media thickness and heart rate, this did not explain the relationship between serum magnesium and CHD mortality or SCD. Future studies should focus on why magnesium associates with CHD mortality and SCD and whether intervention reduces these risks.
Kunutsor SK, Khan H, Laukkanen JA. Serum magnesium and risk of new onset heart failure in men: the Kuopio Ischemic Heart Disease Study. Eur J Epidemiol. 2016 May 25.
Serum magnesium is an essential intracellular cation involved in processes that regulate cardiovascular function and has been linked to the risk of several cardiovascular disease outcomes. We aimed to investigate the association of serum magnesium concentrations with risk of incident heart failure (HF). We studied 2181 middle-aged men without prevalent HF (aged 42-61 years) enrolled in the finnish Kuopio Ischemic Heart Disease prospective cohort study with serum magnesium measurements made at baseline. Hazard ratios (95 % confidence intervals [CI]) for HF were assessed. During a median follow-up of 24.8 years, 278 HF events occurred. Baseline serum magnesium was weakly and inversely associated with several clinical markers and was continuously associated with risk of HF. The age-adjusted HR (95 % CIs) for HF per 1 standard deviation (SD) higher serum magnesium levels was 0.86 (0.76-0.97). The HR (95 % CIs) was 0.87 (0.76-0.98) after controlling for measures of adiposity, socio-economic variables, medical history, blood pressure, renal function, alcohol consumption, and lipids. These findings remained consistent in analyses accounting for incident coronary heart disease. The results were comparable across several clinically relevant subgroups and analyses with atrial fibrillation as a competing risk yielded similar results. Serum magnesium was continuously, inversely and independently associated with future risk of HF. Further research is needed to assess any potential relevance of serum magnesium in HF prevention.
Joris PJ, Plat J, Bakker SJ, Mensink RP. Long-term magnesium supplementation improves arterial stiffness in overweight and obese adults: results of a randomized, double-blind, placebo-controlled intervention trial. Am J Clin Nutr. 2016 May;103(5):1260-6.
BACKGROUND: Epidemiologic studies have suggested a protective effect of magnesium intake on cardiovascular disease risk. However, intervention trials of magnesium supplementation on blood pressure and conventional cardiometabolic risk markers are inconsistent. Effects on vascular function markers related to cardiovascular disease risk have rarely been studied.
OBJECTIVE: The objective was to evaluate the effects of long-term magnesium supplementation on arterial stiffness.
DESIGN: We performed a 24-wk, randomized, double-blind, placebo-controlled intervention study. Fifty-two overweight and slightly obese individuals (30 men and 22 postmenopausal women, mean ± SD age: 62 ± 6 y) were randomly allocated to receive either 3 times daily magnesium (3 × 117 mg or 350 mg/d) or placebo capsules. Twenty-four-hour urine collections and 24-h ambulatory blood pressure assessments were performed at the start and end of the study. Carotid-to-femoral pulse wave velocity (PWVc-f) was assessed at baseline, after 12 wk, and at week 24.
RESULTS: Serum magnesium concentrations did not differ after 12 wk but tended to increase after 24-wk magnesium supplementation compared with placebo by 0.02 mmol/L (95% CI: 0.00, 0.04 mmol/L; P = 0.09). Twenty-four-hour urinary magnesium excretion increased by 2.01 mmol (95% CI: 1.22, 2.93 mmol; P < 0.001) at week 24. PWVc-f was not changed after 12 wk (0.0 m/s; 95% CI: -0.6, 0.5 m/s; P = 0.90) but was improved in the magnesium compared with the placebo group by 1.0 m/s (95% CI: 0.4, 1.6 m/s; P = 0.001) after 24 wk. Office and 24-h ambulatory blood pressure levels were not changed. No adverse events were observed.
CONCLUSION: Our data indicate that a daily magnesium supplement of 350 mg for 24 wk in overweight and obese adults reduces arterial stiffness, as estimated by a decrease in PWVc-f, suggesting a potential mechanism by which an increased dietary magnesium intake beneficially affects cardiovascular health. This trial was registered at clinicaltrials.gov as NCT02235805.