Magnesium: What It Is, How Much You Need, and Where to Find It

Magnesium is a veritable workhorse among the minerals your body needs. You need it for muscle function, normal heart rhythm, blood glucose control, nerve function, to transport otherminerals throughout the body, and for basic energy needs, according to the National Institutes of Health. (1)

Here’s what you should know about how much magnesium you need every day, where to get it from, and when you should think about taking magnesium supplements.

Magnesium is a mineral that is naturally found in plant and animal foods. For humans, it’s an essential nutrient, helping with more than 300 different biochemical reactions that take place in our bodies all the time, the NIH notes. (1)

As an ionic or “charged” particle, magnesium is an important electrolyte that supports optimal nerve and muscle function, including involuntary muscles like the heart. It may helplower blood pressure。In fact, one study in July 2016 in the journalHypertension, found that participants who received additional magnesium through a supplement of about 300 milligrams (mg) per day for three months increased their blood levels of the mineral and reduced their systolic blood pressure (the top reading of a blood pressure reading) by two points and diastolic blood pressure (the bottom number on that reading) by 1.78 points. (2)

Magnesium — along with other nutrients likechromium— also helps调节血糖。According to the Linus Pauling Institute at Oregon State University in Corvallis, magnesium intake has been shown to improve insulin sensitivity and may be useful for the prevention and management of type 2 diabetes. (3人体需要足够的镁中rt immunity and turn food into energy.

What’s more, magnesium helps the body absorb other essential minerals, includingcalcium和potassium— meaning it plays a role in all the functions that those minerals support, too (such as maintaining bone health).

You may also be surprised to learn that magnesium is the third most prevalent mineral in human bones, after calcium and phosphorus — and 60 percent of the magnesium in the body is stored in the skeleton, according to the NIH. (1)

Recommended dietary allowances (RDAs) are the average daily intake levels (of any given vitamin or mineral) that sufficiently meet the nutrient requirement for most healthy individuals. RDAs for magnesium vary by age and gender, according to the NIH: (1)

Recommended Amount for Women

• Ages 14 to 18360 mg/day
• Ages 19 to 30310 mg/day
• Women 31 and older320 mg/day

Recommended Amount for Men

• Ages 14 to 18410 mg/day
• Ages19 to 30400 mg/day
• Ages 31 and older420 mg/day

Recommended Amount for Infants

• Up to 6 months old30 mg/day
• 6 to 12 months75 mg/day

Recommended Amount for Children

• Ages 1 to 380 mg/day
• Ages 4 to 8130 mg/day
• Ages 9 to 13240 mg/day

Generally speaking, some of the bestfood sources of magnesiumare those that are high infiber。According to the NIH, they include: (1)

• Spinach每½杯78毫克煮沸
• Cashews74 mg per 1 ounce (oz) dry roasted
• Black beans60毫克½杯煮熟的
• Edamame50 mg per ½ cooked and shelled
• Salmon24 mg per 3 oz cooked
• 花生酱49 mg per 2 tablespoons
• Whole-wheat bread46 mg per 2 slices
• Some brands of mineral water(check labels, amounts vary greatly)1 mg per liter to 120 mg per liter

The above list includes good sources not only of magnesium, but also phytonutrients, which are plant chemicals that promote health and immunity. Refining and processing foods depletes naturally occurring magnesium, so as usual, it is best to opt for minimally processed sources.

Other foods with magnesium include:

• Yogurt
• Bananas
• Avocados
• Potatoes
• Milk
• Raisins

Learn More About Foods High in Magnesium

Some of the early symptoms of a deficiency are muscle weakness, fatigue, low appetite, nausea, and vomiting. Because these symptoms may be due to a multitude of other issues, it is advisable to see your physician if you are experiencing them.

Blood tests但是，由于我们将大部分矿物存储在骨骼中，因此并不是整体镁商店的有效度量。一些研究人员认为，许多慢性镁缺乏症的病例都无法诊断。（1）这种不认可的缺乏症是有问题的，因为它可能导致许多常见的医疗状况，包括cardiovascular disease, diabetes, andosteoporosis, according to an article published in January 2018 inOpen Heart。(4)

Risk Factors for Magnesium Deficiency

Although Americans generally don’t get optimal amounts of magnesium every day,deficienciesthat result in health harms are relatively rare, according to Harvard Health. (5) The following would put you at risk for deficiency, notes the Harvard T.H. Chan School of Public Health: (6)

• Alcohol abuse
• Advanced age
• Crohn’s orceliac disease, which can prevent propernutrient absorptionin the body
• 糖尿病和服用medication for diabetes
• Certain medications that deplete magnesium, including somediuretics,质子泵抑制剂, and antibiotics

Learn More About Signs and Symptoms of Magnesium Deficiency

没有足够的镁会破坏每天发生的许多身体过程。新证据表明，随着时间的流逝，后果可能会加起来，并可能在这些慢性问题中发挥作用。

Preventing High Blood Pressure, Heart Disease, and Stroke

“Your heart is essentially a large muscle,” saysOlivia Wagner, RDN, an integrative registered dietitian nutritionist in Chicago. Magnesium works in tandem with calcium to support blood pressure, and it also may balance lipid levels, all of which helps promote healthy heart function, she says.

A study published in January 2016 in theJournal of the American Heart Associationfound a link between low serum magnesium levels and both coronary heart disease (CHD) and sudden cardiac death, but it remains unclear exactly why the relationship exists or if supplementing with magnesium would lower the risk of either. (7)

Several studies have associated healthy levels of magnesium in the diet with a lower incidence of stroke, but because much of the research on both CHD and stroke is from observational studies, this is just an association; more data are needed from randomized clinical trials to determine if higher magnesium levels directly reduce the risk of these conditions, notes a February 2018 review in the journal营养物质。(8)

RELATED:The 6 Best Nutrient Pairings For Your Heart

Preventing or Managing Type 2 Diabetes

A review of observational research, published in theWorld Journal of Diabetesin August 2015, on magnesium and type 2 diabetes suggests that adequate magnesium intake may lower the risk of the disease, because people who get adequate magnesium in their diets seem to have lower incidence of this chronic health problem. (9) “If you’ve been diagnosed with胰岛素方面介绍eorprediabetes, then taking extra magnesium may really help you,” saysRobin Foroutan, RDN, who specializes in integrative and functional medicine at the Morrison Center in New York City.

Furthermore, if you have diabetes, magnesium supplementation may also help keep you healthy. Having type 2 diabetes raises your risk for heart disease, but people with a higher blood level of magnesium are less likely to develop coronary heart disease, per a March 2018 study in the journal营养物质。(10)

RELATED:你需要知道的关于镁和2 D型iabetes

Maintaining Bone Health and Preventing Osteoporosis

Magnesium is essential for bone formation, says Foroutan. It also indirectly affects bone density because it is part of the system that regulates the important bone nutrients calcium andvitamin D。Thus, it is important to get enough magnesium to support your skeleton.

As a study on middle aged and older adults in the November 2017 issue of营养物质suggests, consuming magnesium-rich foods may play an important role in preventing diseases like osteoporosis and bone fracture. (11)

Easing Migraine

In the few clinical trials conducted, magnesium helped lower the frequency, duration, and severity of migraine. (12) The therapeutic dose formigraine treatmentis well above the recommended maximum from supplements, so it is safest to seek the help of a healthcare professional for advice and monitoring. Still, Foroutan says that for somepeople with migrainewho aren’t actually low in magnesium, megadoses — or excess magnesium — may be helpful in inhibiting attacks.

Learn More About the Health Benefits of Magnesium

You may not need a supplement, and you can optimize your intake through dietary changes, says Wagner.

Still, some healthcare professionals believe that much of the public has what’s called “subclinical magnesium deficiency,” which means that a person runs chronically low in the mineral but not low enough to be defined as deficient. According to the aforementioned study in the journalOpen Heart, there may be several factors at work in this widespread deficiency, including lack of nutrients in soil and an excess intake ofprocessed foods, which are stripped of minerals. (2)

If you’re dealing with certain symptoms that might suggest you’re running low in magnesium — frequent headaches, muscle cramping at night or with exercise, fatigue, orconstipation— you may benefit from a magnesium supplement, says Wagner. Talk to a healthcare professional to see what’s right for you.

Overall, magnesium supplements are safe, as long as you’re following the label or a doctor's recommendations and not consuming excessive amounts, says Foroutan. Taking too much will act as alaxative— one clue that you’re going overboard.

While your kidneys do flush out excess magnesium (it is a water-soluble mineral), getting too much of the mineral from supplements can cause diarrhea (often accompanied by nausea andabdominal cramping) — and in very large doses can cause more serious problems like retention ofurine, difficulty breathing,irregular heartbeat, and cardiac arrest. Those more serious consequences have resulted from magnesium doses exceeding 5,000 mg per day, according to the NIH. (1)

People with acid reflux who take proton pump inhibitor medications for more than one year are at risk for low magnesium levels, according to the U.S. Food and Drug Administration. The FDA warns that even magnesium supplements didn't raise levels enough in these people. (13)

Because extra magnesium is eliminated by your kidneys, anyone who has renal impairment should not take supplements without discussing it with a healthcare provider. Likewise, anyone taking certain medications, includingbisphosphonates, antibiotics, diuretics, or proton pump inhibitors should be aware of possible adverse drug-nutrient interactions. Be sure to speak with your healthcare team before starting this or any other supplement.

If you do decide to take a magnesium supplement, you’ll need to decide what type to take. Different types of magnesium vary in price, how well your body can absorb them, and potential side effects. Research suggests that magnesium aspartate, lactate, chloride, and citrate are best absorbed by our bodies. Whereasmagnesium oxide和magnesium sulfate(also known as Epsom salt), which can also be taken orally, are less easily absorbed.

The types of magnesium most likely to cause diarrhea are magnesium carbonate, chloride, gluconate, and oxide, according to past research. (14) Keep in mind that supplements can be a natural way to relieve constipation due to their laxative effect.

Magnesium threonate is a form of magnesium that may pass into the brain more efficiently, thus both Wagner and Foroutan use it when addressing mood, sleep, and cognition issues.

Magnesium clearly plays a large role in the healthy function of your body. It’s possible that you are running low on magnesium, especially if you’ve been struggling with insulin levels, muscle cramps, or migraine. Magnesium-rich foods and supplements can safely help get your levels back up so you can feel great.

Additional reporting byJessica Migala。