Everything You Need to Know About Magnesium

When it comes to magnesium, there is a lot to know. There are different forms and each form serves its own purpose. Some types will affect other medications you may be taking so it is important to speak with your doctor before adding magnesium to your health routine. 

What is magnesium and why is it good for you?

Magnesium is a mineral an that your body needs for over 300 bodily processes including making DNA, generating energy in cells, helping your muscles contract, transmitting nerve impulses, building strong bones, regulating stress hormones, blood pressure and blood sugar levels.[1] It is a building block for your teeth and bones and helps your metabolism [2]. 

Making sure you’ve got enough magnesium is important.

If you have a magnesium deficiency you might experience irritability and muscle weakness - including a weakened heart [3]. It has been directly linked to arrhythmias, and may play a role in stroke, heart disease and bronchial asthma [4]. 

Groups at risk for deficiency include older adults, people with Crohn’s, Celiac disease and other gastrointestinal medical conditions, and those who take medications that reduce magnesium absorption from the gut.

Sometimes conditions and/or medications increase magnesium loss instead of preventing absorption. People who have type 2 diabetes or chronic alcohol dependance can experience magnesium deficits due to diet and other factors, as well as increased loss via urinary excretion [5].

Drugs that drain magnesium include: 

  • Proton pump inhibitors (PPIs) used to treat acid reflux and ulcers [1] - for example, omeprazole (Losec), esomeprazole (Nexium) and lansoprazole (Prevacid).
  • Diuretics such as furosemide and hydrochlorothiazide 


Magnesium supplements can be used for specific issues and conditions including constipation, heartburn or indigestion [6].  Dissolved in a hot bath, magnesium (aka Epsom Salts in this case) can help relieve stress and anxiety, calm your nervous system and ease bruises and minor sprains [7].  Later in the article we go through the various types and their common uses in more detail.


It is always important to let your health care professional know what supplements and medications you are taking. And there are often side effects you should be aware of before adding anything new to your regimen. 

Does Magnesium Cause Diarrhea?

Yes, no and maybe. Yes, if you injest too much of many forms.  No, magnesium used in soaks and baths are unlikely to cause diarrhea. And maybe, each person is different and your body may tolerate some forms more than others. 

Nausea and stomach cramps are other common side effects. Extremely high amounts may cause serious adverse side effects. 

How much magnesium should I take per day?

The Recommended Dietary Allowance (RDA) for magnesium is 400 milligrams (mg) per day for men and 310 mg per day for women [5].

Ideally, your body would get all the magnesium you need through food, however, 48% of American adults don’t. 

This is where supplementation can be helpful.

How Does My Body Absorb Magnesium?

Your body absorbs different kinds of magnesium in different ways. If the form you take dissolves well in liquid, your gut will be better able to absorb it. Some studies show that “magnesium in the aspartate, citrate, lactate, and chloride forms is absorbed more completely and is easier for your body to use than magnesium oxide and magnesium sulfate [5].” It’s also important to be aware of other supplements, like zinc, that may impede your body’s ability to use what you give it.

What Kinds of Magnesium Supplements Are There? 

The most common forms include: 

  • Magnesium Glycinate or Magnesium Bisglycinate 
  • Magnesium Citrate
  • Magnesium Oxide
  • Magnesium Aspartate
  • Magnesium Chloride
  • Magnesium Lactate 
  • Magnesium L Threonate
  • Magnesium Malate
  • Magnesium Taurate
  • Magnesium Sulfate
  • Magnesium Orotate

What’s the best time of day to take magnesium?

Magnesium’s different uses often inform when and how to take it. It is always a good idea to follow your doctor’s instructions and the package directions. If your doctor’s instructions are different then the general guidelines below, follow your medical professional’s advice. Usually, taking magnesium with an evening meal is recommended if you are using magnesium for sleep enhancement or laxative purposes.

How long does it take for magnesium supplements to work?

Some forms have their effect in 30 - 60 mins, while other forms work overnight. Refer to the packaging of your magnesium for further details. 

Should I take magnesium with food?

In many cases, yes. Make sure to check your magnesium’s label and follow your doctor’s instructions.  Generally, it’s a good idea to take magnesium with meals and a glass of water, since it can upset your stomach or cause diarrhea on an empty stomach [8]. It’s important to take your recommended dose accurately and at the time(s) you are directed. Too much magnesium in the blood can cause serious side effects.Tell your doctor if symptoms of low magnesium blood levels (such as muscle cramps, tiredness, irritability, depression) last or get worse. If you think you may have a serious medical problem, get medical help right away.

What's the best magnesium to take?

That depends. What do you want it to do for you? You have specific needs and health goals and different forms of magnesium will help you reach them. Give some thought to the outcomes that you want to achieve and then discuss them with your doctor.

A quick quide to Magnesium. Table shows the different types at a glance with best uses, absorption and considerations

Types of Magnesium

What does “chelated” mean?

Let’s look at an example - magnesium bisglycinate. It is a “chelate” because an amino acid (glycinate) has been attached to a mineral atom (magnesium). Together, the mineral and amino acid create a “very stable form of magnesium” that’s less likely to cause you any gastrointestinal distress and it also reduces the laxative effect [9]. Note: Don’t use a chelated form of magnesium if you are allergic to it, or if you have kidney disease [10].

Magnesium Glycinate

This form of magnesium is well-tolerated and absorbed. Magnesium glycinate is combined with the amino acid, glycine. Glycine works with other chemicals in your brain to promote feelings of calm, improve your sleep quality and promote a circadian rhythm [11]. Anecdotal evidence suggests that it may reduce the effects of anxiety, stress, sleep disturbances and depression.  “Magnesium glycine may have stress-relieving or calming abilities that reduce the effects of anxiety, depression, sleep disturbances, and stress. Most of the evidence behind these uses is anecdotal, and more scientific research is needed [6].” See our recommendation for magnesium bisglycinate in our shop. 

Magnesium Bisglycinate vs Magnesium Glycinate

Is there a difference? No. Magnesium bisglycinate means that one magnesium atom is attached to two glycine molecules. “Bis” means "two", so “bisglycinate” is simply more precise. 

Magnesium Citrate

Magnesium citrate is a form of magnesium salt combined with citric acid. Studies show that it has a better absorption rate than magnesium oxide or amino-acid chelate preparations [12]. Often used to ease constipation, magnesium citrate’s gentle laxative effect is caused by it’s ability to draw water into the bowels and get things moving [13]. Magnesium may relax the intestine muscles which also helps. 

Magnesium Oxide 

Magnesium oxide is the most common type of magnesium. There are powder, tablet, capsule and liquid forms. This is the magnesium you find in “Milk of Magnesia”. It has a strong laxative effect and can also be used to provide relief for heart burn and upset stomach issues [14]. 

However, it does not play well with other medications. Magnesium oxide can make it harder for your body to absorb other medications. It’s best to take your medications 2 hours before or 2 hours after you take magnesium oxide [15]. Side effects include bloating and diarrhea if you take too much [16].It is not as bioavailable as other forms, so it may not be the best choice for a magnesium supplement.

Magnesium Aspartate

Magnesium aspartate is a blend of aspartic acid and magnesium that forms a salt. Since it is one of the more easily absorbed forms, it can be used as a dietary supplement [17]. It can be tricky to find as it is uncommon. 

Magnesium Chloride

Magnesium + chlorine = magnesium chloride. It’s naturally found in seawater and salt lakes. This form is often used as a dietary supplement to increase magnesium levels. It comes in tablets or capsules for oral consumption and also as flakes that can be dissolved in a bath or foot soak. Magnesium chloride can lower anxiety, reduce pain and promote a restful sleep [9]. And in case you’re wondering, Magnesium chloride and epsom salts are not the same thing - they are chemically different. Epsom salts are magnesium + sulfate.  

Magnesium Lactate

Naturally produced by your muscles and blood cells by combining magnesium and lactic acid, magnesium lactate is easily absorbed and a good dietary supplement choice. It can also help alleviate leg cramps and provide menstrual pain relief [6].

Magnesium Malate

Made from magnesium and malic acid, magnesium malate is very well absorbed in the body. It offers many of the benefits of other forms of magnesium including laxative and antacid effects. Additionally, it can be used to prevent or treat headaches [18]. Other potential uses include elevating your mood, enhance your exercise performance and treating conditions like chronic fatigue syndrome and fibromyalgia, but more research is needed in these areas [9]. 

Magnesium L-Threonate

Formed by combining magnesium with threonic acid, this version of magnesium is easily absorbed and “may significantly increase magnesium levels in brain cells”[6].  Recent studies suggest that magnesium l-threonate has the potential to improve cognitive function and be beneficial for age-related cognitive decline, but more research is needed [19]

Magnesium Taurate

Magnesium and the amino acid, taurine, form magnesium taurate. Both help regulate blood sugar and reduce inflammation [20]. Magnesium taurate also has a “synergistic effect for lowering blood pressure [21].  

Magnesium Sulfate

Also known as Epsom salt, magnesium sulfate is made from magnesium, sulfer and oxygen. Many people add it to a bath or soaking solutions to help relieve minor sprains and bruises [7]. It comes in various forms including powders and sprays [22].This form of magnesium is also used as an anticonvulsant, a cathartic and and electrolyte replenisher in the treatment of pre-eclampsia and eclampsia [23]. 

Magnesium Orotate

Magnesium orotate is a combination of magnesium and orotic acid. The orotic acid transports the magnesium into your cells and acts as an antioxidant [24].  It’s currently being studied for heart health and energy production.

What is the best Magnesium Supplement?  

By now you've read through the different types, the ways they're used, how much your body needs and when you should avoid adding magnesium to your supplement regimen. So what is the bottom line? 

The best supplement depends entirely on you and what you want from magnesium. 

Natural products and supplements have effects on your body and they need to be carefully considered and discussed with your health care professional. We've made a visual reference guide to help you along in your journey. 

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