Magnesium For Anxiety: Does It Work?

Magnesium is the second most important mineral in our cells, after potassium, says Rana Ahmad, a registered dietitian at Northwestern Medicine Palos Hospital in Palos Heights, Illinois. Magnesium helps regulate energy production, blood pressure and glucose, our body’s stress response and so much more, she explains. It’s not surprising magnesium plays so many roles—some researchers estimate that 70% of enzymes in the body need magnesium to work properly.^[2]Barbagallo M, Veronese N, et al. Magnesium-An Ion with Multiple Invaluable Actions, Often Insufficiently Supplied: From In Vitro to Clinical Research. Nutrients. 2023;15(14):3135.

“One of the most interesting things that we know about magnesium is that it seems to increase gamma-aminobutyric acid (GABA), the primary relaxation neurotransmitter,” says David C. Leopold, M.D., the medical director at Hackensack Meridian Integrative Health and Medicine at Jersey Shore University Medical Center.

Research suggests magnesium may also inhibit NMDA receptors, which lower the effects of glutamate, the primary excitatory neurotransmitter, Dr. Leopold continues. “The combination of these two effects seems to produce the stress-reducing and relaxation effects of magnesium,” he says. These effects may explain why some research suggests a magnesium deficiency can lead to anxiety. If less magnesium is present, NMDA receptors may become more active.

So how do you know if you’re getting enough of this mighty mineral? Measuring blood levels is how magnesium status is typically assessed. But it’s possible to have low magnesium despite having a normal blood level. To start, your blood accounts for only about 1% of your body’s magnesium stores.^[3]Zielińska M, Łuszczki E, et al. Dietary Nutrient Deficiencies and Risk of Depression (Review Article 2018-2023). Nutrients. 2023;15(11):2433. Additionally, your body can shift magnesium away from your bones to help keep your blood level stable.

A symptomatic magnesium deficiency caused by low blood levels is uncommon in generally healthy individuals. A more likely scenario is having “magnesium inadequacy”—a situation where you’re getting some magnesium, but not quite enough.

The recommended daily allowance (RDA) of magnesium for adults is 310 to 320 milligrams for women over the age of 19 and 400 to 420 milligrams for men over the age of 18. An additional 40 milligrams each day is recommended during pregnancy.

Magnesium is widely found in both plant and animal food sources—even water contains some magnesium. Some examples of dietary sources of magnesium include:

• Fruits (fresh or dried)
• Nuts or seeds
• Soy products
• Peas or beans
• Whole grains
• Dark, leafy greens
• Dairy products

“The best sources of magnesium are in pumpkin seeds, almonds, black beans and dark leafy vegetables like spinach,” says Ahmad.

As a general rule, fiber-rich foods tend to also be high in magnesium.

“Some fish like salmon and mackerel contain magnesium as well,” Dr. Leopold adds.

Despite magnesium’s presence in many foods, most Americans aren’t getting enough. Dr. Leopold points out that older adults, in particular, may be less likely to have adequate magnesium intake.

Increased intake of processed foods and decreased magnesium content in soil are possible explanations for Americans not meeting their magnesium needs. Either way, Dr. Leopold recommends getting more magnesium from foods as opposed to relying on dietary supplements, as magnesium-rich foods contain many other essential nutrients, too.

Still, in some cases, getting magnesium from dietary sources alone may be more difficult, such as for those with chronic diarrhea or type 2 diabetes.

Chronic stress may be another risk factor for low magnesium, according to a 2020 review in Nutrients.^[4]Pickering G, Mazur A, et al. Magnesium Status and Stress: The Vicious Circle Concept Revisited. Nutrients. 2020;12(12):3672. During times of stress, your kidneys may filter more magnesium out in your urine. This magnesium loss can make it harder for your body to adapt to stress.

Your doctor or dietitian can help you determine your individual magnesium needs and how to best meet them.

Yes, there is some research that shows magnesium may help reduce anxiety, says Dr. Leopold. A trial of magnesium for anxiety may be appropriate based on current evidence, he says. He stresses the need for individuals to be evaluated by a clinician to ensure this approach is appropriate for them, noting that, “natural supplements do not replace conventional medical care.”

“While research in this area is limited, there is evidence showing that magnesium can help with mild anxiety symptoms,” adds Ahmad. Experts define mild anxiety as occasional nervousness and unease. Mild anxiety would not usually get in the way of your daily activities or cause you significant distress on a recurring basis.

One small, randomized controlled trial of 264 adults with low to low-normal magnesium blood levels showed an improvement in self-reported measures of anxiety and stress after eight weeks of magnesium supplementation.^[5]Pouteau E, Kabir-Ahmadi M, et al.. Superiority of magnesium and vitamin B6 over magnesium alone on severe stress in healthy adults with low magnesemia: A randomized, single-blind clinical trial. PLoS One. 2018;13(12):e0208454.

Meanwhile, a 2017 systematic review looked at 18 clinical studies examining the impact of magnesium supplements on people prone to having anxiety. Nine studies showed taking a magnesium supplement improved anxiety. Still, further research from well-designed studies is warranted.^[6]Boyle NB, Lawton C, et al. The Effects of Magnesium Supplementation on Subjective Anxiety and Stress-A Systematic Review. Nutrients. 2017;9(5):429.

Still, experts note research on the benefits of magnesium for anxiety is still emerging, and the effects of magnesium on reducing anxiety are not considered proven or efficacious.

“Not all magnesium is made the same,” says Ahmad. Magnesium comes in different salt forms with slightly different properties. Talking with your doctor is always recommended before starting a supplement, she adds, as they can help you choose the best form for your individual needs.

“I tend to lean towards the powder form of magnesium,” says Ahmad, who notes it has better absorption than capsule forms. Powder forms can be mixed into a liquid and are also often preferred for individuals who have trouble swallowing pills. Dr. Leopold also recommends powder forms when possible.

Below are specific types of magnesium supplements Dr. Leopold recommends for individuals taking magnesium for anxiety.

Magnesium Citrate

“Magnesium citrate is quickly absorbed in the body but may cause some gastrointestinal distress like cramping or diarrhea,” says Ahmad. Speaking with your physician and adhering to the directions on the container can help alleviate possible gastrointestinal issues.

The citrate form of magnesium can help with anxiety and stress and may improve sleep and muscle tension, notes Dr. Leopold.

Magnesium Glycinate

The benefits of magnesium glycinate are similar to magnesium citrate, says Dr. Leopold. But Ahmad notes that magnesium glycinate is less likely to cause unwanted gastrointestinal side effects. Dr. Leopold points to the attached molecules called glycine—a natural chemical in the body. “Glycine has been shown to help with sleep,” he explains. Research shows glycine has a calming effect in the brain.

Magnesium L-threonate

Magnesium L-threonate is one of the most well-absorbed magnesium salts. In addition, some research shows supplementation leads to higher magnesium levels in the brain. Magnesium threonate has become very popular because it may help support brain health, adds Dr. Leopold. While the research is not as robust for this form, he thinks it’s a reasonable magnesium choice for individuals who are interested in taking it.

What to Avoid

Ahmad specifically recommends avoiding magnesium glutamate and aspartate salts due to possible risks of neurotoxicity. Magnesium oxide is another form you may want to avoid, she adds, as this magnesium form is poorly absorbed and more likely to cause diarrhea.

“I prefer products that have been validated by a third-party source,” says Dr. Leopold. This is important because, like other supplements, magnesium products are not regulated by the Food and Drug Administration (FDA) in the same way medications are.

To be safe, choose a product with a United States Pharmacopeia (USP) verified check mark or National Sanitation Foundation (NSF) certification.

It’s best to take a magnesium supplement 30 minutes before bedtime, says Ahmad, as magnesium may help with sleep, thanks to its calming effects.

Dr. Leopold also recommends taking magnesium supplements at night—except for one. Magnesium L-threonate is best taken in the morning, he adds. Some researchers are looking into whether magnesium L-threonate supplementation might help with focus and memory, but as Dr. Leopold previously noted, current research on this supplement type is not very robust.^[7]ShZhang C, Hu Q, et al. A Magtein®, Magnesium L-Threonate, -Based Formula Improves Brain Cognitive Functions in Healthy Chinese Adults. Nutrients. 2022;14(24):5235.

“You may start to notice a difference in as little as a few days,” explains Ahmad, noting that in some cases, it can take up to two weeks of taking magnesium to notice any effects.

“In my clinical experience, the reduction of anxiety and stress is also fairly rapid, usually within a few days,” agrees Dr. Leopold. But anxiety and stress are complex issues with many causes, he adds, noting a varied response also depends on other factors being addressed.

Depending on the form of magnesium used, you might notice a difference in how quickly the calming effects kick in after taking a dose. “Magnesium glycinate is not absorbed as quickly as magnesium citrate,” says Ahmad.

Magnesium supplements are generally well tolerated, says Dr. Leopold, but nausea and diarrhea are possible side effects. He recommends starting with a low magnesium dose—about one-quarter of the recommended starting dose. If tolerated, you can increase your dose every few days until you reach the full dose, he explains. Taking magnesium with food may also help prevent gastrointestinal side effects.

You should always talk with your doctor before starting a supplement, says Ahmad. Dr. Leopold agrees, noting a magnesium supplement may not be safe for everyone, including people with the following conditions:

• Kidney disease
• Inflammatory bowel disorders
• Irregular heart rhythms

Ahmad and Dr. Leopold both point out that too much magnesium is not safe. Very large doses can be fatal, primarily due to effects on the heart, says Dr. Leopold (though he notes that at recommended doses, magnesium is generally very safe to take). However, he cautions against taking multiple supplement products containing magnesium, which may lead to a significant increase in the cumulative dose.

Interactions are another concern with magnesium supplements. If you take blood pressure medications, it’s possible magnesium could cause your blood pressure to drop too low, says Dr. Leopold. Some other notable interactions include:

• Potassium-sparing diuretics
• Oral bisphosphonates
• Tetracycline or quinolone antibiotics

There are many more possible interactions. Always check with your doctor or pharmacist to ensure magnesium is safe to take with your other medications and supplements.

If you’re having anxiety issues, Dr. Leopold recommends seeing a doctor as soon as possible to make sure there’s no other underlying medical cause. He frequently recommends talk therapy for anxiety or stress issues.

Two forms of evidence-based psychotherapies that help with anxiety symptoms and do not rely on medications or supplements include cognitive behavioral therapy and somatic experiencing therapy.

Anxiety is a highly treatable condition, Dr. Leopold explains. While natural supplements may play a role, he says a multifactorial approach is often needed, which may include medication, talk therapy and lifestyle modifications.