Magnesium Oxide Vs Magnesium Glycinate: What Are The Differences

Ask someone if they have a deficiency in their diet and you’ll almost always get a response of protein, calcium, iron, b-vitamins, or vitamin d. Rarely do you ever hear someone expressing concerns over magnesium deficiency. Yet, the reality is nearly 75% of the population is not getting enough magnesium in their diet, in what is now being called, “the invisible deficiency”. Although there are many types of magnesium, we are going to discuss the differences between magnesium oxide vs magnesium glycinate, the benefits, and which specific type of magnesium is the most preferred.

What Is Magnesium Oxide 

Magnesium is an essential cofactor and mineral for many enzymatic reactions especially those that are involved in energy metabolism, and neurotransmitter synthesis.  

Studies have shown that magnesium supplements have been linked to numerous health benefits, including the ability to fight inflammation, improve immune health, relieve constipation, improve sleep quality, and lower blood pressure.

With many different types of magnesium available, magnesium oxide is the most commonly used form of magnesium in supplements. The main reason for this, is cost. Magnesium oxide is the cheapest form of magnesium produced, thus the most cost effective for manufacturers.

Magnesium oxide is an inorganic salt of magnesium formed with ions of magnesium and oxygen. Magnesium oxide like all other forms of magnesium is used as a supplement to maintain adequate magnesium in the body. 

Typically, magnesium oxide is used as an antacid, to relieve heartburn, acid indigestion, and as a short term and effective laxative, as well as blood pressure and migraines.

What Is Magnesium Glycinate

Magnesium glycinate is a combination of elemental magnesium and the non-essential sleep-inducing amino acid, glycine. Glycine, much like GABA is an inhibitory neurotransmitter, and acts as an excitatory modulator of the N-methyl-D-aspartate (NMDA) subtype of ionotropic glutamate receptors. Essentially, inhibitory neurotransmitters block or inhibit certain brain signals in your central nervous system. Glycine inhibits excitatory neurons, promoting a sense of calmness, relaxation, and anxiolytic effects.

Magnesium glycinate is also one of the best absorbing forms of magnesium. Studies have shown that glycine improves sleep quality, promotes healthy sleep patterns and REM cycles [R].

Benefits Of Magnesium

Magnesium oxide and magnesium glycinate will share many of the same benefits. The major difference are the specific therapeutic uses, and that magnesium glycinate is combined with the amino acid glycine, which can help improve sleep parameters. Low magnesium levels, in general have been associated with an increased risk of type II diabetes, osteoporosis, high blood pressure, and muscle weakness.

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Helps With Constipation

Magnesium oxide has been shown to help with constipation, due to properties as a laxative. Magnesium has an osmotic effect, meaning it draws water into the intestines, making it easier to pass bowel movements and stool.

One study found that magnesium oxide significantly improved bowel movement, in patients with chronic constipation [R].

In Japan, magnesium oxide is used as a therapeutic treatment for chronic constipation since the 1980’s and is used as a laxative by more than 10 million patients [R].

Improves Sleep Quality

Magnesium has an essential role in the neural transmission both in the pre and post synaptic membrane, as a natural agonist of NMDA and GABA which play a crucial role in sleep regulation [R].

Magnesium also plays a role in activating the para-sympathetic nervous system, which is the system to help you calm down and relax. To fall asleep and stay asleep, your body and mind need to in a relaxed state. 

Studies indicate that magnesium regulates the hormone melatonin, helping guide your sleep cycle [R]. As you age, magnesium levels decline, putting you at major risk for magnesium deficiency. A 2012 study showed that 500 mg of magnesium oxide taken daily for 8 weeks, significantly improved sleep time, sleep efficiency, and enhanced REM [R].

Several studies have shown that magnesium deficiencies are directly correlated to suboptimal sleep quality, shorter sleep duration, and decreased melatonin concentrations, also referred to as the “sleep hormone.”

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Animal studies have shown that glycine, may improve sleep in those with insomnia. A study published in the journal Nueuropyschopharmacology, found that Glycine significantly reduced wakefulness and non-rapid-eye-movement (NREM), sleep during the first 90 minutes, compared with the control group.

Together, magnesium and glycine are bound to form a unique and powerful sleep-inducing combination.

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Has Anxiolytic Effects

Magnesium modulates activity of the of the hypothalamic pituitary adrenal axis (HPAA) which is a central part of the stress response system. Magnesium glycinate supplementation has been shown to attenuate the activity of the HPAA, including a reduction in cortisol from the central and peripheral responses of this system [R,R]. In vivo investigative studies have shown, that magnesium deficiency induces anxiety Therefore, including magnesium rich foods or supplement may benefit anxiety through moderating the stress response [R]. 

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Better Bone Health

As we age, your bones progressively lose density and become frail. Studies have shown that greater intakes of magnesium can increase bone density through conserving skeletal muscle mass, which helps prevent bone frailty and age-related diseases such as sarcopenia and osteoporosis [R]. Taking a high-quality magnesium supplement, that has 100% of your recommended daily intake, is crucial for preventing bone frailty and potential fractures, especially in high impact endurance sports, that demand and induce more physical stress.

It's important to note, that low magnesium levels make vitamin d ineffective and cannot be metabolized without sufficient levels of magnesium. Bioavailability is important in this case, as low absorbing types of magnesium will not be as effective. Studies have shown that magnesium glycinate is far more bioavailable than magnesium oxide.

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Magnesium Oxide Vs Magnesium Glycinate

Although magnesium oxide and glycinate have many of the same and shared benefits, there are a few subtle differences, that you should consider.

Better Sleep With Magnesium Glycinate

Magnesium glycinate exhibits all of the same benefits as other forms of magnesium yet with an added sleep-inducing layer. Studies have shown that glycine is a powerful inhibitory neurotransmitter, promoting a sense of calm, relaxation, and anti-anxiety effects. When these two compounds are bound together, sleep latency, sleep duration, and sleep quality are all improved from multiple mechanisms, inducing greater rest and relaxation.

For Constipation Used Magnesium Oxide

As a laxative, studies have shown that magnesium oxide is the preferred form of magnesium, to help with constipation.

Magnesium Glycinate Is More Bioavailable Than Magnesium Oxide

Studies have shown that magnesium glycinate is better absorbed, thus will help increase magnesium levels, and help with deficiency more so than magnesium oxide [R]. This is a very important factor to consider, especially since the intended purpose of supplementation is to increase bioavailable levels of magnesium.

Magnesium Dosage Recommendations

The recommended daily allowance (RDA) of magnesium is between 310-420mg per day depending upon age and gender. National surveys have shown that the average intake of magnesium per day, is 326mg [R]. Studies show that 400-500mg of magnesium is recommended for sleep and anti-anxiety effects, while 350mg is needed for exercise performance benefits [R]

Magnesium Oxide Vs Magnesium Glycinate: Takeaway

Despite the form of magnesium you use, according to the World Health Organization, as much as 75% of the U.S. adult population does not meet the U.S. Food and Drug Administration’s Recommended Daily Intake of 420 mg per day. Depending upon the benefits you are looking for, or benefits you want to avoid, using a magnesium supplement can help with obtaining better quality of life, sleep, and wellness. Magnesium glycinate is always preferred over oxide, as it does have better bioavailability, and will produce better results and efficacy


Looking For The Best Magnesium Glycinate Supplement For Better Sleep and Relaxation? ZMT Contains 422mg of Magnesium Glycinate 100% your Daily Recommended Value

Swolverine’s ZMT maximizes your body’s ability to stimulate muscle growth, by promoting high-quality sleep, and naturally boosting testosterone levels. With clinically dosed sleep ingredients such as Melatonin, GABA, Theanine, Tryptophan, Valerian Root, Magnesium Glycinate, and powerful adaptogens like Ashwagandha, Zinc, Rhodiola Rosea, Fenugreek, and Tongkat Ali, ZMT is the perfect nighttime elixir for restful recovery and sleep.

We believe that everyone can optimize not only their athletic performance but their human potential. The way we believe we can optimize performance is through transparency, clinically effective doses, and clinically proven ingredients with evidence-based outcomes. We provide the nutrients you need to power your active lifestyle. 



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