Magnesium has an incredibly broad range of activities in the body. It is actually responsible for over 1000 different reactions. One of the key body systems that it has notable influences on is the cardiovascular system.
I have often discussed its influence on the nervous system, and that is partially why it has so much influence on the cardiovascular system, but also it has a regulatory effect upon cardiac muscle and the blood vessels too.
Blood pressure regulation
One area that magnesium really has a significant influence is blood pressure. More specifically in aiding in lowering it or at least keeping it in safe parameters. A meta analysis conducted by Zhang et al (2016) found that magnesium supplementation had a notable impact upon raised blood pressure. This effect appears to get more and more pronounced the higher the baseline blood pressure was - ie the higher the blood pressure, the greater the effect (Kass & Sullivan, 2017).
How does it have this effect? Well, purely & simply it works as a vasodilator, meaning it widens blood vessels. It does this by relaxing the muscular walls of the vessels. Asd they relax the vessel widens and the pressure against the vessel wall decreases.
It is also worth noting that magnesium does help to regulate electrolyte balance in the body. By doing so this can help regulate how much water we retain. If we hold on to too much water, the volume of our blood increases and that raises blood pressure too.
Regulating heart rhythm & contraction
It is well documented that magnesium is vital for regulating heart rhythm. Magnesium deficiency is know to increase the risk of arrhythmias. Whilst this condition requires drugs to safely mage it, it appears that magnesium supplementation may well enhance therapy further. Use of supplements was shown to be beneficial in issues such as atrial fibrillation, especially in cases of post operative cardiac surgery patients (Shecter, 2010).
Magnesium also offers promise in issues such as heart failure and cardiomyopathy. Magnesium deficiency is associated with poor clinical outcomes in such patients and supplemental magnesium has shown benefits in areas such as improved exercise tolerance (Gottlieb, 1990).
Endothelial function & atherosclerosis
Integrity of the endothelium (the highly active lining of our blood vessels) is vital for long term cardiovascular health. It is damage to the endothelium that sets the stage for cardiovascular disease. Magnesium can reduce the risk of endothelial damage by making the endothelial cells far more resilient to damage. A study conducted by Maier (2014) showed that an adequate intake of magnesium was associated with reduced arterial stiffness and enhanced endothelial function. How much impact this has upon diseased vessels is not clear, but certainly as a preventative measure, magnesium has some real relevance.
Magnesium can also help support a reduction in inflammation, which is at the core of atherosclerosis and lesions in the blood vessels.
Impact upon cholesterol levels
This is an area that is gathering a little more momentum, but certainly needs more research. There does appear to be some positive impact upon cholesterol levels when magnesium intake is adequate. A few studies have shown that adequate magnesium intake is associated with a reduction in LDL cholesterol and an increase in HDL cholesterol (Guerrero-Romero & Rodriguez-Moran, 2000).
Food vs Supplements
So here is one of the biggest issues I find that causes contention. Should we be getting it from food or from supplements. Well, you have probably figured out by now that I am in favour of both. Food first clearly, but supplements are powerful tools to address specific issues.
Foods like green leafy vegetables, seeds, nuts etc are all great sources of magnesium, that is for sure. However, in the modern age so many people struggle to even get the baseline amount, let alone hit a level that has potential therapeutic benefit.
This is where a supplement can kick in and bridge any gaps. Just make sure you choose a high quality supplement, and ideally speak to a nutrition practitioner for targeted advice.
References
Gottlieb, S. S. (1990). Effects of intravenous magnesium sulfate on arrhythmias in patients with congestive heart failure. American Journal of Cardiology, 65(5), 1397-1401.
Guerrero-Romero, F., & Rodriguez-Moran, M. (2000). Hypomagnesemia, oxidative stress, inflammation, and metabolic syndrome. Diabetes/Metabolism Research and Reviews, 16(5), 355-360.
Kass, L., & Sullivan, K. R. (2017). Effect of magnesium supplementation on blood pressure: a meta-analysis. European Journal of Clinical Nutrition, 71(2), 288-293.
Lindberg, J. S., Zobitz, M. M., & Poindexter, J. R. (1990). Magnesium bioavailability from magnesium citrate and magnesium oxide. Journal of the American College of Nutrition, 9(1), 48-55.
Maier, J. A. (2014). Endothelial cells and magnesium: implications in atherosclerosis. Clinical Science, 127(7), 375-388.
National Institutes of Health. (2021). Magnesium: Fact Sheet for Health Professionals.
Shechter, M. (2010). Magnesium and cardiovascular system. Magnesium Research, 23(2), 60-72.
Zhang, X., Li, Y., Del Gobbo, L. C., Rosanoff, A., Wang, J., Zhang, W., & Song, Y. (2016). Effects of Magnesium Supplementation on Blood Pressure: A Meta-Analysis of Randomized Double-Blind Placebo-Controlled Trials. Hypertension, 68(2), 324-333.
