Constipation can also be brought on by certain health conditions or medications.
Some people use magnesium-based laxatives as a way to relieve constipation.
Various forms of magnesium are used for constipation because they can draw water into the intestines.

Fiordaliso / Getty Images
Fiordaliso / Getty Images
What Is Magnesium?
What Are Food Sources of Magnesium?
Foods are a fantastic way to get your magnesium needs met.

The recommended maximum tolerable intake of magnesium for adults is 350 mg per day to prevent overdose.
While generally safe when used as directed, certain precautions are necessary.
Although considered safe for short-term use, prolonged reliance on magnesium may result in dependence.
Magnesium works as anosmotic laxativeto relieve constipation by increasing the water content and volume of the stool.
Several guidelines recommend the use of magnesium salts for constipation.
A study was conducted in 34 female subjects with an average age of 40 and mild to moderate constipation.
The results showed that using magnesium oxide for four weeks improved overall constipation symptoms.
However, the sample size was small and limited to female subjects from Japan.
Therefore, the results might not be the same in other populations.
Various magnesium salts are used as osmotic laxatives, but few studies compare the different salt forms.
Magnesium Oxide
As suggested, magnesium oxide has been studied for constipation.
Pros and cons include:
Magnesium Citrate
Magnesium citrate has been used for constipation as well.
The following includes its typical dosage:
Drink 1 cup of liquid with each dose.
Magnesium citrate may be taken as a single daily dose or in divided doses.
To improve the taste, you may add some lemon juice.
Pros and cons include:
Which Magnesium Is Best for Constipation?
Studies suggestmagnesium citrateis a more potent saline laxative.
For example,magnesium hydroxide(milk of magnesia) is also used as an antacid.
Therefore, the form of magnesium used for constipation is individualized.
How Long Does Magnesium Take to Start Working?
Magnesium hydroxide, citrate, and sulfate generally produce a bowel movement within 30 minutes to six hours.
Side Effects
Magnesium supplements can causediarrhea,nausea, andvomiting.
Symptoms of magnesium toxicity include the following:
Who Should Avoid It?
Avoid magnesium if you’re allergic to it or its components (parts).
Seek immediate medical attention if you have asevere allergic reaction(itching, hives, shortness of breath).
The kidneys are responsible for regulating magnesium levels in the blood.
However, if you have kidney problems, the risk of magnesium buildup increases.
High doses of zinc supplements can interfere with magnesium absorption in the body.
Diuretics or water pills, such as Lasix can increase the loss of magnesium in the urine.
This means some supplement products may not contain what the label says.
However, magnesium citrate is generally suggested to have a stronger laxative effect than other magnesium preparations.
For children under 6 years of age, c’mon consult a healthcare provider.
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