Magnesium Carbonate vs Citrate

Magnesium Carbonate Vs Citrate – Which Is Best For Your Sleep Goals

Magnesium Carbonate vs Citrate

Magnesium is an essential mineral similar to sodium, calcium, and potassium. Like other minerals, magnesium works best in the form of a chemical salt mixed with some other component. Magnesium carbonate combines magnesium with the chemical salt of carbon and three oxygen atoms. Magnesium citrate involves magnesium combined with citric acid. So which is better? Let’s take a closer look Magnesium carbonate vs citrate and find out.

Both of these are commonly used to enhance sleep, and both seem to be effective. Let’s look at the difference between the two and see why they work for sleep quality improvement.

What Are the Benefits of Magnesium Carbonate?

Let’s start with magnesium carbonate, which mixes magnesium with carbonate in salt form.

Improves Sleep Quality

Research shows that most people are functionally low in optimal magnesium amounts. Magnesium is essential for the function of the nervous system and, when used as a supplement, calms the nerves, reduces restlessness, and helps protect the nerves against becoming over-excitable.

When taken for sleep, it has known positive effects. It can reduce the time it takes to get to sleep, improve sleep quality and lengthen the number of sleep hours. How it causes sleepiness is less understood; however, it likely stabilizes nerve endings in the brain just as much as it does the nerves and muscles outside the brain.

Reduces Stress and Anxiety

Anxiety is generally caused by stress and an overactive stress response. Part of anxiety involves what’s known as neuroinflammation – or inflamed and irritable nerve cells within the brain. If you take magnesium to protect those nerves, you can protect your inflamed nerves and allow them to heal properly. This reduces the perception of stress.

Enhances Cognitive Functioning

Remember that your thoughts are simply your brain’s nerves communicating with one another. You won’t think properly if your brain is not communicating because of low magnesium levels. Stabilized nerves that talk to one another more effectively allow you to think more clearly and efficiently.

What Are the Benefits of Magnesium Citrate?

Magnesium is found in magnesium citrate, just as it is in magnesium carbonate. Let’s look at what you can expect out of this supplement in addition to those just listed.

Supports Healthy Bones and Teeth

While we think of calcium and our bone health, magnesium also plays a big role in protecting both our bones and teeth. If your magnesium levels are low, you cannot build bone effectively. Proper magnesium intake helps calcium enter cells to strengthen bone cells and teeth. Experts say that 40 percent of your magnesium resides in these strong tissues.

Aids in Digestion

Both magnesium citrate and magnesium carbonate play a role in digestion. With calcium citrate, the citrate component has a mild to moderate laxative effect, so this helps enhance movement within the bowels. Magnesium carbonate does not have the same effect but may ease heartburn pain instead.

Supports Heart Health

Magnesium is essential for proper electrical activity in the heart. Without it, abnormal electrical activity in the heart can be dangerous to your health. Magnesium also acts on the blood vessels to reduce blood pressure. This may reduce stroke risk and reduces the risk of heart attacks due to hypertension (high blood pressure).

What is the Difference Between Magnesium Carbonate and Citrate?

If magnesium is found in magnesium citrate and magnesium carbonate, is there any difference in which one you take? Maybe. Let’s look at the differences.

Chemical Composition

The chemical composition of any salt depends on both parts of the salt. In these cases, we are dealing with citrate (which comes from citric acid) and carbonate (which comes from lime or chalk). They differ in some of the side effects each has and in how easily their dietary supplements might be absorbed once you consume the liquid or pill.

Absorption Rate

Researchers look at the bioavailability of a supplement or drug as a good measure of its ability to be absorbed by the gut. In general, magnesium carbonate is about 20%; however, other sources say it is about 30%. Magnesium citrate is generally considered to be more bioavailable at 30 to 90%.

Magnesium Carbonate

Magnesium carbonate is not all bad, despite its reduced bioavailability. It is inexpensive and has excellent antacid power. It is easily mixed with water for double duty internally and within the gut itself.


Both magnesium carbonate and magnesium citrate are relatively inexpensive. The goal would be to get a formulation you can take. The pills are very large, so the liquid and powdered forms are sometimes preferred.

Which Is Better for Sleep Goals?

women sleeping on bed

Which formulation should you take if you’re only taking magnesium for sleep? Both have magnesium in each supplement, which is conducive to better sleep.

Magnesium Carbonate

Magnesium carbonate is inexpensive. If it helps induce sleep, you should continue using it. On the other hand, large pills, in particular, have reduced bioavailability, so what you take may not be entering the bloodstream from the gut.

Magnesium Citrate

Magnesium citrate is easily tolerated and absorbs better than magnesium citrate. It is okay to take for sleep unless the side effect of loose stools is prohibitive.


Q. How much magnesium should I take for sleep?

The dose of magnesium depends on the supplement; however, if you take between 100 mg and 350 mg per day, you should experience sleep enhancement almost immediately.

Q. Is magnesium carbonate or citrate better for sleep?

Both magnesium citrate and magnesium carbonate work for sleep enhancement; however, if we look at bioavailability alone, magnesium citrate will theoretically be the better option.

Q. Are there any side effects of taking magnesium?

Remember that magnesium citrate can lead to loose stools, so it can’t be used if this side effect is too apparent. Magnesium carbonate will not generally lead to this issue.



  • Christine Traxler, M.D.

    Dr. Traxler has over 17 years of experience writing in the medical field. She specializes in medical, health and wellness, dermatology, pregnancy, nursing, and medical assisting. She has a B.S. in Biochemistry and a Medical Doctorate. Visit LinkedIn page.

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