About half of themagnesiumin your body is found in your bones.
The rest supports cell function throughout the body.
Magnesium also is important to your immune system and keeps it working well.

Verywell / Cindy Chung
This article explains some of the health benefits of magnesium.
It offers information about taking supplements, including what to look for.
It also presents possible side effects and drug interactions.
Everyone needs adequate levels of magnesium, and most people get them.
These systems become overexcited by chemical messages and related stimuli.
This can cause an abnormal, excessive response from their muscles.
This common in people who use stimulant medications.
It can show up as muscle twitches.
It also may cause people to clench their jaws or gnash their teeth.
That’s often the case for people who find this happens while they’re sleeping at night.
Some researchers recommend magnesium teas or tablets to help with symptoms of teeth grinding, also known asbruxism.
Magnesium also may help with restless legs syndrome (RLS).
With this condition, people have an annoying urge to move their legs, again often at night.
Not all research is clear on the health benefits of magnesium, though.
They were unable to confirm that magnesium is effective and its role remains unclear.
This possiblelaxative effectof magnesium appears to come through two pathways.
Pumpkin seeds, for example, contain very high amounts of magnesiumabout 152 milligrams (mg) per ounce.
Even adding normal amounts of a vitamin or mineral may be toxic.
Toxicity
Toxic amounts of magnesiumcan cause problems with the kidneys.
It may also cause severe reactions that affect the intestines, heart, and lungs.
Be sure to read supplement labels carefully to prevent excess intake.
What Is Hypermagnesemia?
Hypermagnesemia is the abnormal buildup of magnesium in your body.
This can happen if your kidneys are impaired.
Hypermagnesemia can lead to heart rhythm problems, respiratory distress, and even cardiac arrest.
It also is sold as a powder to mix into a liquid.
Magnesium supplements also are paired with different chemicals.
For example, magnesium salt products are absorbed at different rates in the small intestine.
This means they may deliver magnesium to the body more slowly.
Different dose levels are necessary for the effects to be felt.
Keep this in mind when reading research results and talk to your healthcare provider before taking it.
Choosing a Magnesium Supplement
Start by checking the labels on magnesium packaging.
This will allow you to find the active dosage as well as any other ingredients in the product.
They may include flavorings, fillers, or binders.
These independent test sites can help you to know if you might trust what you see on the label.
Summary
Magnesium does a lot of work in your body.
But supplements are not for everyone.
People who have limited kidney function should avoid taking magnesium because of the risk of toxicity.
Other serious side effects include electrolyte imbalances and permanent digestive tract damage.
If you plan to take magnesium, be sure you know what you’re getting.
It’s available in different mixtures and forms that can change its effects.
Read product labels and be sure to buy from a reputable store or online provider.
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