What Happens To Your Poop When You Take Too Much Magnesium Stearate

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Even if you've never heard of magnesium stearate, there's a very good chance you've consumed it at some point in your life. According to a 2017 study published in Toxicology Reports, magnesium stearate is a food additive that can be found in anything from dietary supplements and pharmaceutical pills to baking ingredients and spices when it's in its powder form.

Although considered non-toxic, when too much magnesium stearate is ingested, it acts as a laxative. In other words, you can be having a fine day for yourself, but if you exceed the proper amount of magnesium stearate, that fine day could quickly devolve into you needing to spend some quality time on the toilet with a severe case of diarrhea. That's why knowing what products contain magnesium stearate is important, and — fun fact — it's not just in medication and baking ingredients.

Because magnesium stearate is a type of salt made up of mineral magnesium and stearic acid (which is a saturated fat), it can be found in natural oils, like cottonseed, palm, and coconut. Salmon, chicken, chocolate, and walnuts also contain it, as do some dairy products like eggs and cheese.

If you want to make sure you don't end up accidentally inducing diarrhea or creating an immediate need to have a bowel movement, then you want to keep your magnesium stearate consumption within a healthy range. According to the National Center for Biotechnology Information, that means staying below 2,500 milligrams per kilogram of your body weight a day. Granted, this is going to take a bit of math, but if you convert your body weight from pounds into kilograms — this is where online conversion charts come in handy — then multiply the kilograms by 2,500, you'll have the appropriate total of milligrams of magnesium stearate for your body on a daily basis. For example, if you weigh 150 pounds, then your magnesium stearate intake shouldn't exceed 170,000 milligrams a day.

Magnesium stearate is considered a "flow agent" or, more specifically, a lubricant by pharmaceutical companies. This lubricating property prevents pill-form medication and supplements, as well as other products, from sticking together. Magnesium stearate also allows pills to move more seamlessly through the gastrointestinal tract. Because of this, it's easy to see why, in excess, it can irritate the intestines and bowels. When this happens, it's only natural that you might feel the intense need to poop, or diarrhea may occur. (Here is every type of poop, explained.)

Although the likelihood of consuming too much magnesium stearate, especially via medication or supplements ­— the latter of which contains less than 20 milligrams (below 1%) per pill, per Consumer Lab — isn't high, too much magnesium can have side effects, including nausea or vomiting, hypotension, weakness, and breathing issues. That said, overdosing on magnesium so much so that it's a cause for concern isn't just rare; magnesium stearate isn't even one of the four forms of magnesium likely to cause unpleasant symptoms in the event of an overdose (via Medical News Today).

Ultimately, whether it's magnesium stearate, magnesium carbonate, or some other form of magnesium, it's all about moderation. Most things we put in or on our bodies can become problematic if we overdo it, so the point is to never overindulge in anything and always pay attention to what your body is trying to tell you. In other words, if you suddenly have diarrhea, there's likely a reason for that, and it's worth looking into what you consumed. 

Diarrhea can easily be managed by resting, taking an over-the-counter bismuth subsalicylate like Pepto-Bismol or Kaopectate, and staying hydrated. If symptoms persist, contact your doctor, in case your diarrhea wasn't caused by magnesium stearate and there's another issue at play.