Can Magnesium Help You Poop?

What to know about using magnesium for constipation

Magnesium is essential for your heartbeat regulation, blood pressure, nerve transmission and muscle contraction. Yet, dietitians rarely get questions about these important roles. Instead, they most frequently get questions about magnesium's poop-inducing potential. So, we're jumping right into this popular topic.

Here's what you need to know if you are interested in trying magnesium to help you poop.

What Is Magnesium?

First, let's start with a bit of background. Magnesium is the fourth most prevalent mineral in the body and is needed by over 300 enzymes. In addition to the functions mentioned above, magnesium is essential for energy production, DNA synthesis and blood glucose regulation. Along with sodium, potassium and calcium, magnesium is an electrolyte in the body playing a key role in fluid balance. According to the National Institutes of Health, consuming low amounts of magnesium could increase the risk for cardiovascular disease and strokes, hypertension, type 2 diabetes, migraines and ADHD. Furthermore, a 2018 publication in Nutrients suggests that magnesium could protect you from chronic pain and anxiety and help treat cognitive disorders such as Alzheimer's disease as well. Yet, amid these vital roles, its ability to alleviate constipation is what first comes to mind for many.

a collage with a bottle of Magnesium pills
Getty Images

Why May Magnesium Work for Constipation?

Magnesium acts in two different ways to potentially relieve occasional constipation. First, magnesium has an "osmotic laxative" effect, meaning it pulls water into the intestines. What this does is soften waste products, which, in turn, keeps things moving toward the exit. Second, magnesium relaxes intestinal muscles, which also aids in the transit process. These actions are why magnesium is a primary ingredient in some over-the-counter laxatives.

Things to Know Before You Try It

Taking small doses of a magnesium supplement can be an effective way to relieve occasional constipation—if you know how to use it properly.

1. Type of Magnesium Supplement

You won't find "magnesium" listed by itself on a supplement label. Instead, it will be bound to an acid or element, and this influences the supplements' function and bioavailability in the body. When it comes to helping you poop, magnesium citrate is considered the top choice. Bound to citric acid, this form is highly absorbable and has a slight calming effect for some people. Supplements with this form of magnesium are widely available and usually found in capsule or powder form. An alternative form that may provide constipation relief is magnesium oxide.

2. Dosage

Magnesium citrate commonly comes in either capsules or liquid, and we recommend you follow the container instructions of the brand your doctor recommends. Effects from magnesium citrate can be felt anywhere from 4 to 24 hours after taking and should be relatively mild (as in you don't have to stay close to the bathroom). Rather, you should just feel like you normally do when you need to poop.

Because of how magnesium works, make sure to take it with an 8-ounce glass of water and stay hydrated. If you think you might need a higher dosage, talk to your health care provider beforehand. Too much magnesium citrate can lead to the opposite problem—diarrhea.

3. Usage and Contraindications

Magnesium citrate is considered safe to use for occasional constipation in healthy individuals. However, it's not meant to be an ongoing solution for chronic constipation. In these instances, it's important to see a health care professional to identify the root cause. Be aware that taking magnesium supplements in any form may influence the absorption of certain antibiotics and medications used to manage blood pressure or promote bone density. Also, people who are pregnant, breastfeeding or have chronic medical conditions should consult with their doctor before using.

4. Using Food as a Source

Don't forget about magnesium-rich foods like leafy greens, legumes, nuts and seeds. The RDA for magnesium for healthy adults is 400 to 420 milligrams for men and 310 to 320 mg for women. According to the NIH, dietary surveys show that most people get less magnesium than this from their diet each day. While most people don't meet the diagnostic criteria for a deficiency, many may have magnesium insufficiency due to ongoing intakes below needs. One sign of low magnesium is constipation, so you may find that simply increasing magnesium-rich foods prevents occasional constipation from ever being a problem.

Was this page helpful?
Related Articles