Are You Getting Enough Magnesium?

Anxiety, poor sleep, and migraines — is more magnesium the answer? Magnesium supplements are getting more mentions on social media, with people touting their mental health benefits.

As a vital component in the body’s many processes, magnesium aids in everything from muscle and nerve function to regulating blood pressure.

The mineral, which is found in foods like nuts, beans, and whole grains, is involved in hundreds of chemical reactions that help with storing energy, developing bones, growing cells, and more.

“Magnesium has wide-reaching effects as an essential nutrient for our bodies,” says Dr. Lisa Koers, a physician at Integrative Health and Wellbeing at NewYork-Presbyterian, in collaboration with Weill Cornell Medicine.

So how much magnesium should you be getting, and when can supplements help?

“Most people will do a good job of meeting their magnesium needs by eating whole foods, assuming they don’t have health conditions that affect how their body absorbs it,” says Dr. Koers. “A healthy lifestyle is the biggest bang for your buck, but there’s potential benefit to incorporating targeted magnesium supplements for those who may need it.”

Dr. Koers shares more about magnesium with Health Matters, including information about who is at risk of deficiency and when to consider supplementation.

What role does magnesium play in our bodies?
Dr. Koers: Magnesium is important for metabolism, bone development, the nervous system, and the transmission of electricity through the heart.

It has the potential to help control blood sugar levels and alleviate a variety of symptoms, including anxiety and muscle spasms. Studies have also found that higher magnesium intake is associated with a reduced risk of developing type 2 diabetes, as well as with potential migraine relief.

How can you tell if your magnesium is low?
There are a variety of ways to measure magnesium, such as testing serum levels, but they may not be reliable indicators. This is because serum levels of magnesium are tightly controlled by the body, and most magnesium is stored inside cells or bone, making levels difficult to assess.

A more practical approach often used is a clinical assessment of risk factors and symptoms.

What are the symptoms of magnesium deficiency, and who is at risk?
Magnesium deficiency may develop if we’re not eating enough magnesium-rich foods, or if we’re not absorbing magnesium properly via the digestive tract.

There’s a slew of conditions that can be associated with magnesium deficiency, such as muscle spasms or cramps, asthma, osteoporosis, and kidney stones. A variety of symptoms can be present that are not specific to magnesium deficiency, such as fatigue, anxiety, migraines, palpitations, and digestive complaints, so it’s a good idea to have a discussion with a healthcare provider to consider your risk factors and predisposing conditions.

Many factors can put a person at increased risk of magnesium deficiency, such as a chronic disease or genetic differences in how someone metabolizes nutrients. People who have acid reflux and are taking acid-blocking medications are especially at risk.

With the incorporation of modern fertilizer into industrial farming practices, we have seen a decline of magnesium content in fresh fruits, vegetables, and cereals, which could impact the amount of magnesium people are consuming daily.

What foods are good sources of magnesium?
Magnesium is an essential mineral — we have to consume it through our diet, as it’s not produced by the body. The recommended dietary allowance for women is between 310 and 320 milligrams a day, and for men, between 400 and 420 milligrams daily.

Nutrients are best absorbed and utilized by the body when they’re consumed as food. Studies have shown that the way our bodies utilize magnesium is also intertwined with vitamin D, zinc, and calcium, so if we turn to supplements before first considering diet, there’s the potential to inadvertently throw other systems out of balance.

My recommendation is to take a food-first approach, especially incorporating whole foods into the diet, such as:

• Unrefined whole grains
• Nuts such as almonds, cashews, and peanuts
• Leafy greens such as spinach
• Black beans and soybeans

What should people know about magnesium supplements?
Magnesium supplements have good therapeutic potential for many people, but I would recommend speaking to a clinician who has specific training in prescribing supplements in a way that’s safe and evidence based.

There are many forms of magnesium available. What you’re getting with a magnesium supplement is magnesium bound to something else, either an anion or an amino acid, which affects its solubility and bioavailability, or its use in the body.

Overall, the broad evidence for using one specific form of magnesium for one specific condition — such as one type for anxiety or another for muscle health — is lacking. In general, I recommend choosing a form that’s more readily absorbed by the body.

Magnesium oxide is among the most commonly used forms due to its low cost and high elemental magnesium content, but this form is also less soluble and bioavailable compared to other magnesium compounds. You’ll see it in laxative preparations because it’s not very well absorbed by the digestive tract and cleans out the bowels.

Magnesium citrate and magnesium glycinate are thought to be more bioavailable and absorbable forms of magnesium, although evidence to support this is mixed. I will often prescribe magnesium glycinate to address issues such as anxiety or headaches.

If somebody wants to start taking magnesium, I generally start with a lower dose, and I’ll often prescribe it for around bedtime, because it can be helpful for relaxation and sleep. If anything changes with their medications or supplement regimen, adjustments may be needed.

Looking at the bigger picture, especially considering the way that magnesium interacts with other nutrients in the body, it’s important to make sure that we’re first optimizing our lifestyle when we’re considering taking a supplement for things like stress, anxiety, or high blood pressure. Take a look at things like your nutrition, sleep, relationships, and daily physical activity before going straight to supplements to address symptoms.

A supplement should not be taken long term without reassessing why you’re using it.

Are there any side effects of magnesium supplements? Who should not take it?
The most common side effect of taking too much magnesium is loose stools or diarrhea. It’s a sign that you either need to choose a different formulation or decrease your dosage.

People who have kidney disease are at high risk of developing adverse effects from magnesium supplements because their bodies will not excrete it well.

Individuals who have myasthenia gravis, a chronic autoimmune disorder, should not take magnesium, nor should people taking angiotensin-converting enzyme (ACE) inhibitors, which are medications commonly used to treat high blood pressure and heart problems. A variety of medications can potentially interact with magnesium, so it is best to speak with a physician before starting a magnesium supplement.