Arrhythmias are heart conditions that happen when you have an erratic, or irregular, heartbeat.

They can start in the atria or the ventricles, which are your heart’s upper and lower chambers, respectively. Arrhythmias can cause your heart to beat either too slow (bradycardia) or too fast (tachycardia).

An arrhythmia can even lead to a premature or extra beat.

Ventricular arrhythmias are the ones that happen in your heart’s lower chambers. There are two main types of ventricular arrhythmias, according to the National Heart, Lung, and Blood Institute.

The first is ventricular tachycardia, which means that your ventricles beat faster but regularly. A long lasting ventricular tachycardia — more than a few seconds — can lead to the second and more severe type: ventricular fibrillation. Ventricular fibrillation can result in cardiac arrest and death.

Magnesium plays a role in keeping a steady heart rhythm, according to the Office of Dietary Supplements (ODS).

So, you may be wondering whether magnesium may help manage these conditions. This article takes a look into the role of magnesium in ventricular arrhythmias.

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Magnesium plays an essential role in heart function. It helps regulate blood vessel contraction, which helps manage blood pressure.

Magnesium is also in charge of heart muscle contraction — meaning that it helps keep your heart beating.

A typical heartbeat is maintained by multiple electrolytes like sodium, potassium, and calcium. Yet, magnesium is the nutrient responsible for regulating the movement of these electrolytes within the heart’s tissues.

If or when these electrolytes cannot function as they should, it can lead to irregular heartbeat, or arrhythmia.

Research from 2018 linked low blood magnesium levels with an increased risk of atrial and ventricular tachycardia. Magnesium deficiency is also considered a risk factor for atherosclerosis (plaque buildup in the arteries) and heart failure.

In fact, studies show that up to 38% of people with ventricular arrhythmia have a magnesium deficiency, and 72% have excessive magnesium losses.

According to research from 2015, besides stabilizing electrolyte concentrations, magnesium may also help prevent arrhythmias by:

  • acting as a calcium antagonist (meaning that it restricts the amount of calcium that enters the heart cells, allowing the heart to beat more slowly)
  • increasing cell energy levels
  • improving oxygen usage
  • reducing the release of neurotransmitters, such as adrenaline, that speed up your heart rate

A 2018 analysis of 22 studies evaluating the relationship between magnesium sulfate supplementation and arrhythmias found that magnesium may reduce the risk of ventricular and supraventricular arrhythmias by 32% and 42%, respectively.

Research from 2017 suggests that magnesium may have beneficial effects in treating drug-induced ventricular arrhythmias.

It’s important to note that magnesium supplements are not the main treatment for all ventricular arrhythmias. Usually, these conditions are managed with medications and, at times, defibrillation or intravenous (IV) lidocaine, an anesthetic.

However, IV magnesium is the first line treatment for those experiencing a specific type of ventricular tachyarrhythmia called Torsade de Pointes, as long as they have a pulse.

Magnesium may help with Torsade de Pointes, even in people whose magnesium levels are not considered low or deficient, but there isn’t a clear consensus on how beneficial it is yet.

Magnesium is a mineral that’s abundantly present in your body and can be easily found in numerous foods and supplements, according to the ODS.

It is involved in a wide range of bodily functions, including energy production, bone development, and DNA and RNA synthesis. Its role in nerve impulse conduction and muscle contraction is what makes it necessary for heart health.

According to the Food and Drug Administration (FDA), magnesium’s daily value (DV) is 420 mg. The DV of a nutrient tells you how much of it you should consume per day.

However, research suggests that many Western-style eating patterns are low in this mineral. In fact, 2015 research suggests that magnesium intake in the United States barely reaches 225 mg per day.

Magnesium is widely available in multiple foods, such as:

  • pumpkin and chia seeds
  • nuts and legumes
  • spinach
  • potatoes
  • rice
  • yogurt

Evidence from 2016 suggests that your body can absorb up to 76% of dietary magnesium.

Still, common causes of low magnesium levels include:

  • low dietary intake
  • bowel resection surgery
  • malabsorption
  • gastrointestinal losses through diarrhea or vomiting
  • use of certain drugs like insulin, diuretics, and laxatives

Learn more about magnesium and how it benefits your body.

Despite magnesium’s widely explored beneficial effects for ventricular arrhythmias, research from 2016 also reports a lack of consensus on dosage.

Additionally, major studies have also found inconsistent results and warn about the potentially damaging effects of magnesium overload.

Excessive magnesium intake can lead to symptoms like diarrhea, nausea, and abdominal pain. Per the ODS, magnesium toxicity can lead to:

  • low blood pressure
  • blushing
  • urine retention
  • depression
  • muscle weakness
  • difficulty breathing

Severe magnesium toxicity may also lead to irregular heartbeat and cardiac arrest in some people.

While magnesium supplements are generally well tolerated, they can also cause gastrointestinal symptoms, such as diarrhea, nausea, and vomiting.

Be sure to talk with a healthcare professional before trying magnesium supplements or drastically changing your eating patterns.

Check out Healthline’s picks of the 10 best magnesium supplements.

There are quite a few additional recommendations you could follow to improve or manage ventricular arrhythmias and overall heart health.

For starters, according to 2015 guidelines from the European Society of Cardiology, you should be mindful of other electrolytes like potassium to reduce the risk of high blood pressure. High doses of potassium-sparing diuretics are common in people with heart failure.

In addition, research from 2021 suggests that calcium and magnesium compete for absorption in the gut. You may want to avoid consuming calcium-rich foods, such as dairy and leafy greens, and magnesium-rich foods or supplements at the same time.

The American Heart Association (AHA) reports that people with arrhythmias have a higher risk of heart attack, cardiac arrest, and stroke. Addressing any risk factors for heart disease can help support your best health.

Aim to follow a heart-healthy diet and exercise regularly to maintain a weight that’s healthy for you, which may help reduce other risk factors for heart disease, such as high blood cholesterol levels or high blood pressure.

Also consider avoiding or reducing the use of substances that can contribute to an irregular heartbeat, such as caffeine, alcohol, and tobacco.

Lastly, given magnesium’s role in managing ventricular arrhythmias, maintaining optimal magnesium levels is vital.

Research shows that stress can be another cause of low magnesium levels as well as heart disease.

The AHA suggests trying to incorporate some stress-relieving activities into your day. These might include taking a walk in nature, meditating, or reading your favorite book.

Finally, the AHA recently added good sleep hygiene to the list of lifestyle factors that support cardiovascular health. Consider avoiding habits and substances that can compromise sleep quality, and make rest a priority when possible.

Ventricular arrhythmias are a potentially life threatening heartbeat condition in which your heart’s lower chambers beat too fast.

They’re usually treated with a combination of medications, defibrillations, and certain medical procedures.

However, a specific type of ventricular tachyarrhythmia known as Torsade de Pointes may be treated with IV magnesium as well if the person has a pulse — even if the person is not low or deficient in magnesium.

And since magnesium is in charge of regulating your heart’s rhythm, research suggests that magnesium deficiency increases the risk of ventricular arrhythmias.

Magnesium supplementation may help also prevent and reduce ventricular arrhythmias, as well as address many other risk factors for heart disease.

Nevertheless, there is a lack of consensus on adequate dosage, and excessive magnesium intake may cause negative side effects. Talk with a healthcare professional before trying magnesium supplements or changing your diet.

Following a heart-healthy diet, exercising, prioritizing quality sleep, and managing stress are some additional ways in which you could manage and prevent ventricular arrhythmias.