Magnesium – the low-down on using it for IBS

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I have been supplementing with magnesium for a while now, on the advice of a  naturopath who I saw when my son’s asthma was at its worse, which was two years ago now.  Sometimes I take supplements without really thinking too much about their benefits or role in my overall health, and so I went through process of reconsidering what I take and this took me on an interesting trip through google-land finding out more about magnesium and IBS. 

There are so many blogs, forums and articles written on the topic with many, manySwisse Ultiboost Magnesium opinions. All a bit overwhelming, really. Finally, I came across one that made the most sense to me and provided a balanced overview which I found to be helpful, and so I thought I would share it with you.

FYI, in case you are interested, this is the magnesium supplement that I use and intend to continue to use as it is a good quality magnesium citrate. Does anyone have anything that they recommend?

If you are interested in my research on laxatives you might like to read my post “Laxatives may be hindering your health“.

This article is by Dr Barbara Bolen and is sourced from About Health.

Before You Take Magnesium for Constipation

If you suffer from constipation predominant irritable bowel syndrome (IBS-C), you may have come across the recommendation to take a magnesium supplement as a way of regulating your bowel movements and easing constipation. Before taking magnesium, or any vitamin, it is extremely important to be educated about possible risks as well as potential benefits. The following is a discussion of the questions you need to consider to make an informed decision for yourself regarding taking a magnesium supplement.

What Does Research Say?

Although magnesium does have a well-established reputation for its laxatives qualities, there does not appear to be any direct research support for the use of magnesium as a treatment for IBS-C. Of interest is a 2006 study that looked at the relationship between constipation and water, fiber, and magnesium intake. The study was conducted in Japan with a whopping number of 3,835 subjects who were between the ages of 18 and 20. Constipation was not found to be associated with low fiber intake or low intake of water from fluids. Constipation was associated with low intake of magnesium and low intake of water from foods.

What Does Magnesium Do For The Body?

Magnesium is a mineral that is essential for overall physical health. Approximately half of the magnesium in our bodies is found in our bones. The rest serves to help cell functioning throughout the body’s various systems. Magnesium plays an important role in muscle function, heart rhythm, blood pressure, immune system functioning and blood sugar level.

In general, healthy individuals have enough magnesium in their system and do not need to take a magnesium supplement.

The laxative effect of magnesium appears to come through two different mechanisms. Magnesium relaxes the muscles in the intestines which helps to establish a smoother rhythm. Magnesium also attracts water; this increased amount of water in the colon serves to soften the stool, helping to make stools easier to pass.

Does My Doctor Approve?

Before taking supplemental magnesium, or any over-the-counter remedy, it is extremely important that you discuss the matter with your doctor, as only your doctor knows your complete medical history. Your physician will be able to tell you if there is anything about your medical picture that would put you at risk should you start taking a magnesium supplement. A particular red-flag would be raised if you suffer from any kind of kidney disease because magnesium is excreted through the kidneys. If your kidneys are not functioning well, you could be at risk for having excessive magnesium in your system.

What Else Am I Taking?

As a general rule, people tend to view vitamins as harmless substances. However, the possibility for negative side effects exists for vitamins in the same way as for any prescription medication. In the case of magnesium, it may be unwise to take an additional supplement if you are already regularly taking antacids or laxatives that contain magnesium. Read labels carefully so as to prevent a buildup of unhealthy magnesium levels in your body.

Supplemental magnesium also carries the risk of interfering with the effectiveness of some prescription medications. Again, it is essential to discuss the use of magnesium with your doctor if you are taking any of the following:

  • Diuretics
  • Chemotherapy agents
  • Certain antibiotics

How Much Is Safe to Take?

The National Institutes of Health has published a fact sheet that offers a table with an outline of the recommended daily intake of magnesium. The amount recommended varies by age and different guidelines are offered for women who are pregnant or breastfeeding.

Which Type Should I Take?

Magnesium supplements come in a variety of forms, with the most popular being citrate, chelate, and sulfate. There does not appear to be any significant health or absorption differences among the various kinds. Just be careful that the magnesium supplement you choose does not contain calcium, as calcium supplements offer the possibility of constipation. If for other health reasons, your doctor recommends that you take supplemental calcium, discuss the possibility of finding a magnesium/calcium ratio that does not compound your constipation problem.

It is important to know that milk of magnesia is a very different product. Milk of magnesia is not intended to be used as a dietary supplement. Milk of magnesia is an osmotic laxative, which works by drawing water into the intestines. This increase in water stimulates bowel motility and increases the size of the stool so as to prompt a bowel movement. Physicians rarely recommend milk of magnesia nowadays, as there are safer and more effective products available to treat constipation.


Murakami, K., Sasaki1, S., Okubo, H., Takahashi, Y., Hosoi Y., & Itabashi, M. “Association between dietary fiber, water and magnesium intake and functional constipation among young Japanese women” 2007 61:612-622.

Dietary Supplement Fact Sheet: Magnesium. National Institute of Health Office of Dietary Supplements.

DISCLAIMER: The information contained on this site is for educational purposes only and should not be used as a substitute for diagnosis or treatment rendered by a licensed physician. It is essential that you discuss with your doctor any symptoms or medical problems that you may be experiencing.

5 thoughts on “Magnesium – the low-down on using it for IBS

  1. I use Natural Calm magnesium citrate powder in water every day. I have been able to cut back from twice a day to once a day, but I plan to keep using it. It has definitely helped me.

    Liked by 1 person

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