How Magnesium Helps Your Sleep

Ryan Fiorenzi, BS, Certified Sleep Science Coach - Updated on March 22nd, 2023

What is Magnesium?

Magnesium is the fourth most abundant element in your body and is one of 7 essential minerals in the body. It is required for more than 300 different functions in the body. Some of the most important functions include:

  • Regulating muscle (including the heart) and nerve functions, including blood pressure.
  • Playing an important role in energy production.
  • Contributing to bone development and preventing bone loss.
  • Helping control your body's response to stress.
  • Helping maintain blood sugar levels.
  • Maintaining fluid balance.

It isn't produced by your body, you need to get it from food and/or supplementation. Some of the foods with the highest levels of magnesium are almonds, pumpkin, cashews, peanuts, spinach, black beans, dark chocolate, avocados, leafy greens, peanut butter, popcorn, hazelnuts, flaxseeds, coffee, bananas, tofu, whole grains, oatmeal, as well as some fatty fish such as salmon, mackerel, and halibut.

The Relationship Between Magnesium and Sleep

Researchers don't fully understand the effect of magnesium on sleep, though research has shown that low magnesium levels can negatively impact sleep. And there's mounting evidence that magnesium may help improve sleep in some people. One study found that among older adults, supplementation of magnesium improved sleep efficiency, sleep time, sleep onset latency, and reduced early morning awakenings. Another study published in Oxford Academic found that supplementing magnesium was effective for sufferers of restless legs syndrome (RLS) and insomnia.

Magnesium may help sleep as it activates the parasympathetic nervous system, which is responsible for relaxing you mentally and physically. It also regulates melatonin, the sleep hormone. Additionally, it binds to gamma-aminobutyric acid (GABA) receptors, which are responsible for reducing nerve activity. This stress-reducing effect of magnesium may help those who struggle to fall asleep and stay asleep, or who wake up not feeling rested due to stress.

An observational study from France concluded that the addition of magnesium, vitamin B5, and B6 in amounts equivalent to 30% of recommended daily intake produced statistically significant positive effects on stress, sleep, and mood.

Insufficient magnesium is also associated with anxiety and depression, which have a cyclical relationship with insomnia. According to a study published in Duke Health, insomnia may predispose people to anxiety and depression, and anxiety and depression may predispose people to insomnia. A review of 18 different studies found that magnesium supplementation may help alleviate anxiety and stress, which prevent restful sleep.

A study in mice showed that both low and high levels of magnesium may lead to sleep issues.

Signs of Deficiency

Early signs of deficiency include loss of appetite, nausea, vomiting, fatigue, and weakness. A more serious deficiency may include symptoms of numbness, tingling, muscle contractions and cramps, seizures, personality changes, abnormal heart rhythms, and coronary spasms.

Serious magnesium deficiencies are rare and are often due to alcoholism, Crohn's disease, diabetes, celiac disease, chronic diarrhea, intestinal surgery, severe asthma, and some medications. Magnesium deficiency is a widespread health problem, with estimates ranging from 48% to 75% of Americans being magnesium deficient. Groups that are at higher risk include:

  • Elderly
  • Teenagers
  • People with Type 2 diabetes
  • Alcoholics

Early signs of magnesium deficiency include:

  • Fatigue
  • Weakness
  • Appetite loss
  • Nausea
  • Vomiting

More serious signs of deficiency include:

  • Muscle contractions and cramps
  • Seizures
  • Personality changes
  • Numbness and tingling
  • Abnormal heart rhythms

What Forms of Magnesium are Most Assimilable?

There are many different types of magnesium with varying costs, laxative effects, and secondary effects that you should be aware of. The best for people trying to raise their magnesium levels are:

  • Magnesium glycinate - One of the top choices as it's least likely to cause diarrhea and it's one of the most bioavailable and assimilable. Occurs in many protein-rich foods such as legumes, dairy, meat, and fish. The amino acid glycine is used as a supplement to treat insomnia and treat inflammatory conditions such as heart disease and diabetes.
  • Magnesium L-threonate - Easily absorbed, it may be the most effective for increasing magnesium in the brain. For this reason, it's being studied in people with age-related memory loss and depression.
  • Magnesium malate - Great for people with fatigue, as malic acid is a natural fruit acid (also found in wine) that plays a role in ATP synthesis and energy production. Magnesium malate is also very well absorbed and has less of a laxative effect than many other forms.
  • Magnesium orotate - Easily absorbed without a strong laxative effect, its main drawback is that it's expensive. It's popular among athletes and may help people with heart disease.
  • Magnesium citrate - The most popular because it's inexpensive and easily absorbed. It's naturally found in fruits, giving them their sour flavor, and is often used as a preservative and flavor enhancer. As it acts as a laxative, in higher doses it is used for constipation.
  • Magnesium taurate -The top choice for people with cardiovascular issues, because it prevents arrhythmias and protects the heart from damage caused by heart attacks. It also helps regulate blood sugar issues and blood pressure.
  • Magnesium chloride - Though it only contains 12% elemental magnesium, its absorption rate is high and it is great for detoxifying cells, heartburn, and constipation.
  • Magnesium carbonate - A good option for people suffering from acid reflux and indigestion.
  • Magnesium lactate - Easily absorbed and easier on digestion. It's also used as a flavoring agent and food additive to fortify foods.

The ones to avoid for increasing your magnesium levels are:

  • Magnesium oxide - The most common form sold in stores with a low absorption rate. It's the active ingredient in Milk of Magnesia and is used to treat heartburn, constipation, and indigestion.
  • Magnesium sulfate - Also known as Epsom salts, it's great for constipation, though it tastes bad, and is easily overdosed.
  • Magnesium glutamate and aspartate - These become neurotoxins when unbound to other amino acids.

Side Effects & Interactions with Medications

Side effects of too much magnesium supplementation include cramping, diarrhea, and nausea. The forms that are associated with excess magnesium are magnesium carbonate, chloride, gluconate, and oxide. Magnesium is the primary active ingredient in many laxatives, such as Phillips' Milk of Magnesia®, and Extra-strength Rolaids®.

According to the National Institutes of Health, you won't get too much magnesium from food because the kidneys eliminate the excess amounts in the urine. If you're planning on raising your magnesium levels, the best way is to add more magnesium-rich foods to your diet. If you're planning on supplementing magnesium, you should talk to your doctor, especially if you have any digestive issues, diabetes, or immune conditions. There are several drugs that have the potential to interact with magnesium, including:

  • Bisphosphonates
  • Antibiotics
  • Diuretics
  • Proton pump inhibitors

According to Dr. Michael Breus, several supplements that may interact with magnesium:

  • Boron - May slow the processing of magnesium and increase blood magnesium levels.
  • Calcium - It's common advice to take magnesium with calcium, but very high levels of calcium may reduce how much magnesium the body absorbs.
  • Vitamin D - May increase magnesium absorption.
  • Zinc - One study from Illinois found that zinc supplementation may reduce magnesium absorption.

Should You Supplement Magnesium?

There are many causes for poor sleep. Increasing your magnesium intake from food isn't difficult or risky. If it doesn't improve your sleep, you can move on to the next factor to consider.

If you think magnesium could help you relax and stay asleep, it's one of the top choices for supplementation for sufferers of poor sleep. If you have a hard time getting enough in your diet, look into supplementing magnesium after speaking to your doctor. You can discuss if it's a good idea, and if so, develop a plan including how much and how often.

If you're interested in our top choices for sleep supplements, check out the Top Sleep Supplements Backed by Research.