Ask Dr. Casey: A. Fib and Magnesium?
Dear Dr. Casey, I was recently diagnosed with atrial fibrillation. I have heard magnesium is good for heart health and arrhythmias - how much magnesium should I start?
- Dan S
Hi Dan,
You are not alone in getting diagnosed with atrial fibrillation- it’s estimated 5-15% of those over 55 years old have this form of arrhythmia. Its prevalence increases with age, and is also more common in males. It presents as an “irregularly irregular” heart beat, meaning, there may be periods where the heart has no rhythmic, predictable pattern. In patients, this can be asymptomatic, but can also present with feelings of palpitations (sensation of feeling your heart beat or “flip flop” in your chest), fatigue, weakness or dizziness,
Risk of clotting increases with arrhythmias, so oftentimes management includes beginning blood thinning medication. This is something to discuss with your health provider in the context of your other cardiovascular risks and severity afib.
Your question about magnesium is a great one! And you are right, there are a lot of cardiovascular benefits regarding magnesium. Most Americans tend to be deficient in magnesium, likely due to a combination of poor diet, prolonged use of certain pharmaceuticals and environmental influences. Magnesium-rich foods include green leafy vegetables, almonds, cashews, brown rice and avocados. As the standard American diet sadly lacks a variety of magnesium-rich foods, it is estimated that 30% of people are magnesium deficient.
Magnesium is involved in hundreds of cellular processes in the body, which includes conduction of nerve impulses, contraction of muscle cells, and yes - maintaining normal heart rhythms. A 2018 review paper in the journal Open Heart titled Magnesium for the Prevention and Treatment of Cardiovascular Disease discusses the many benefits of magnesium supplementation for heart health, including afib. The paper points out the correlation between high incidence of atrial fibrillation in individuals ranking in the bottom 25% of magnesium stores.
What’s more, magnesium has good evidence for lowering blood pressure, decreasing blood sugar in diabetes, reducing severity and frequency of migraines, promoting bone health to reduce osteoporosis and much more. If I have convinced you that magnesium is generally a wonderful supplement add-on for general health + your heart health, let’s discuss dosing and the form of magnesium to take as there are many types.
For most people who are good candidates for magnesium supplementation, I aim for a dose of 200 - 400 mg of magnesium per day. Magnesium glycinate is one of my favorites as it can have a calming effect on the nerves, be gentler on the stomach (ie, no laxative effect like milk of magnesia) and has also been linked with improved cardiovascular health. I generally advise to take this form before bedtime to help improve sleep, as well. A mixed magnesium blend containing forms of malate, glycinate, and oxide is another commonly found and used combination. Be warned that magnesium citrate and oxide can cause loose bowels even in moderate doses.
As always, you should discuss the form and dose of magnesium and if it is the right supplement for you with your healthcare provider based on your medical conditions, as it may not be appropriate for everyone. Magnesium can be quite marvelous for cardiac health in general!
