Medically Reviewed

Can Magnesium Cause Diarrhea?

Don’t let fear of diarrhea deter you from getting the magnesium you need. With the proper dose, you can forget about digestive distress. Get the facts here.

What is magnesium?

Magnesium is a nutrient that activates enzymes and helps to regulate the levels of calcium, copper, zinc, potassium, and vitamin D in the body. It is an important structural component of bones and teeth, and 60% of the magnesium found in the human body is stored in the skeletal system. Every organ in the body, especially the heart, muscles, and kidneys, needs magnesium. Without enough of it, all of these areas are vulnerable to malfunction.

Magnesium affects more than 300 enzymes in the body and is involved in glucose control (already within normal range), regulating blood pressure (already within normal range), muscle function, and nervous system processing. It is also required for energy production.

Ideally you would get sufficient amounts of magnesium from a healthy diet rich in leafy green vegetables, nuts, seeds, whole grains, poultry, beef, and 70% dark chocolate. While magnesium deficiency is rare, most people in the U.S. probably do not get as much as they should for maximum effectiveness in their bodies.

Magnesium's role in the body

Magnesium plays an important role in relaying signals between your brain and body. It acts as the gatekeeper for the N-methyl-D-aspartate (NMDA) receptors, which are found on your nerve cells and aid in brain development, memory, and learning.

Magnesium also helps to maintain healthy heart function. When calcium enters the heart muscle, it stimulates the fibers to contract. Magnesium provides the counter-effect by helping the muscle fibers to relax. It is this moving back and forth because of calcium and magnesium that maintains a healthy heartbeat.

Health benefits from magnesium supplementation

Magnesium is one of 7 essential macrominerals of which people need to consume at least 100 mg each day. It is vital for many bodily functions and getting enough of it helps you to achieve and maintain optimal health and wellness.

This report contends that oral supplementation of magnesium manages age-related neuroendocrine and EEG changes in humans.

This study found that exercise performance may be compromised with deficient magnesium levels and that supplementation may improve performance parameters in both aerobic and anaerobic exercises. The researchers call for more rigorous large-scale studies.

According to findings from this study, there may be a correlation between PMS-related symptoms and lower magnesium levels. Participants who were deficient in magnesium and supplemented reported noticeable improvement in PMS-related symptoms.

Higher levels of magnesium are needed in order to maintain a healthy pregnancy according to this abstract. The researchers concluded that pregnant women should be counseled to increase their intake of magnesium-rich foods and to supplement at a safe level when needed.

Magnesium plays a role in the regulation of calcium, which makes it essential for bone health. Clinical results have, however, shown mixed results toward magnesium supplementation for bone health.

Does magnesium cause diarrhea?

Magnesium is a key ingredient in most laxatives and antacids, and while they are safe to use, sometimes there can be some rather unpleasant side effects – like diarrhea. The problem is too much unabsorbed magnesium, which attracts water from the surrounding tissues in the intestine or colon, and overstimulates the bowel. This overstimulation can result in cramps and diarrhea.

Generally speaking, the higher the dose, the more likely a person is to experience diarrhea (this also depends on the form). In order to avoid diarrhea, you need to adhere to the tolerable upper limit of the magnesium you are taking. There are also certain types of magnesium supplements that tend to cause diarrhea more than others. The best way to avoid diarrhea is to identify the right kind of magnesium supplement you need, the best brand for you, and follow the recommended dosage.

Do all forms of magnesium cause diarrhea?

The ideal forms of magnesium to use in order to avoid diarrhea are those that are best absorbed by the body, such as magnesium chloride, bisglycinate, and glycerophosphate. These tend to have less of a laxative effect, although any magnesium can cause loose stools, or worse, if taken in high enough doses. There are also certain forms of magnesium, such as magnesium oxide, that are intended to promote stools in cases of occasional constipation due to external factors like travel or change in diet.

Which magnesium form doesn't cause diarrhea?

If you are considering a magnesium supplement and you’d like to avoid diarrhea, you might want to start with a chelated version like magnesium glycinate. The magnesium is combined with the amino acid glycine, making it more gentle on the gastrointestinal tract and more easily absorbed into the body. Since every body is different, you might have to try a few different forms to find the one that works best for you. Hint: If a magnesium is buffered, it means that magnesium oxide has been mixed in with it. If the label tells you the elemental magnesium is less than 10%, it is considered pure. Otherwise, the magnesium has been buffered with magnesium oxide, an osmotic laxative.

Magnesium supplementation

Recommended daily dosage

The recommended dietary allowance (RDA) of magnesium are as follows: adults ages 19 and up 310-320 mg for female and 400-420 mg for male; pregnant persons 350-360mg; and lactating persons 310-320 mg.

Potential side effects and risks

High doses of magnesium can cause nausea, abdominal cramps, and diarrhea. Magnesium oxide can also impact absorption and excretion of antibiotics and other medications. Some medications, like proton pump inhibitors and diuretics, can impact magnesium levels.

When to talk to your doctor

You should always talk to your physician before beginning any supplementation program, especially when you are taking other medications or have pre-existing medical conditions. If you are experiencing chronic diarrhea talk to your doctor as it may be a sign of underlying serious health issues.

Final takeaways

Magnesium is an essential macronutrient that has an impact on every organ in the body, and plays a role in more than 300 enzyme reactions that keep you alive. It is also critical for regulating your heartbeat, controlling your glucose level, regulating nervous system processing, and muscle function.

It’s also the key ingredient in most laxatives and antacids. If you’re taking a magnesium supplement and are concerned about unpleasant side effects like diarrhea, determine what type of magnesium you should take to best meet your needs, find the appropriate dose, and, if needed, adjust dosage. Don’t be afraid to try a few until you find one that is right for you. Care/of has a premium magnesium, The Dream Weaver, that comes from Irish seawater, and contains more than 300 minerals and 72 trace minerals. For more on magnesium, check out this Care/of article.
If you are pregnant or planning a pregnancy and have questions about magnesium as it relates to pregnancy, don’t miss this Care/of article.

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