Heart failure is commonly referred to as the end stage of heart disease – the culmination of all forms of cardiovascular disease. More than 26 million people worldwide have heart failure. Findings from a 2007 study suggested that supplemental magnesium ameliorates symptoms associated with heart failure.

Magnesium is an essential mineral and a cofactor for hundreds of enzymes. It is involved in many physiologic pathways, including energy production, protein synthesis, ion transport, and cell signaling. Magnesium deficiency is linked with increased risk of cardiovascular disease and metabolic disorders, including hypertension and type 2 diabetes. Current magnesium intakes among people living in the United States are below recommended levels of 400-420 milligrams per day for men and 310-320 milligrams per day for women.

The double-blinded, randomized intervention study involved five patients with chronic heart failure. Fifteen of the patients received 800 milligrams of supplemental magnesium oxide daily for three months, while the remainder took a placebo. The study investigators measured small and large arterial elasticity and compliance, hemodynamic parameters, exercise capacity, and quality of life at the beginning of the study and again at one week and three months after the intervention. Several of the patients dropped out of the study, with only five completing the full three-month intervention.

Patients who took the magnesium supplement had improved small arterial compliance, a measure of endothelial function. Reduced compliance is an indication of abnormalities in vascular structure.

This study suggests that supplemental magnesium improves endothelial function in symptomatic heart failure patients. However, this was a very small study group, so further study in a larger group of participants is warranted.

• Link to full study.