The Forbes Health editorial team is independent and objective. To help support our reporting work, and to continue our ability to provide this content for free to our readers, we receive compensation from the companies that advertise on the Forbes Health site. This compensation comes from two main sources. First, we provide paid placements to advertisers to present their offers. The compensation we receive for those placements affects how and where advertisers’ offers appear on the site. This site does not include all companies or products available within the market. Second, we also include links to advertisers’ offers in some of our articles; these “affiliate links” may generate income for our site when you click on them.
The compensation we receive from advertisers does not influence the recommendations or advice our editorial team provides in our articles or otherwise impact any of the editorial content on Forbes Health. While we work hard to provide accurate and up-to-date information that we think you will find relevant, Forbes Health does not and cannot guarantee that any information provided is complete and makes no representations or warranties in connection thereto, nor to the accuracy or applicability thereof. Cas 1309-42-8
Magnesium is an essential macronutrient that the body needs for over 300 biochemical processes. Among its many responsibilities, it plays a significant role in energy production, DNA synthesis and muscle and nerve function.
For those who struggle with obtaining enough magnesium through diet alone, supplements are available and offer magnesium in different forms. Magnesium oxide, in particular, has multiple uses and potential benefits. Scientific research suggests it may help treat heartburn, indigestion, constipation and related health challenges.
Below, experts weigh in on the potential benefits, side effects and uses of magnesium oxide.
Magnesium is a type of electrolyte (an electrically-charged mineral categorized as a healthy metal) responsible for regulating many bodily functions including muscle contraction, the central nervous system, blood pressure, blood sugar levels and more.
Due to its various roles within the human body, sufficient magnesium is necessary for the body to function properly. The Recommended Dietary Allowance for magnesium varies based on age and gender, ranging from 30 milligrams to 420 milligrams. Regularly low magnesium levels can lead to a magnesium deficiency, which could cause quite a few complications.
“Magnesium deficiency (hypomagnesemia) can be associated with negative health outcomes including neurologic, muscular and cardiovascular conditions,” says Michelle Pearlman, M.D., a board-certified gastroenterologist based in Florida.
Certain health conditions like diarrhea and chronic alcoholism can lead to persistent low intake or excessive losses of magnesium, as well as common medications. Blood pressure medications in particular are among those that may deplete magnesium.
Some foods, like dark leafy green vegetables, are rich in magnesium. However, the National Institutes of Health notes that many people in the U.S. receive less than the recommended amount of this important nutrient through diet alone, and deficiency is associated with inflammation. Further, fertilizers and pesticides can prevent magnesium absorption in vegetable food sources.
For those needing an additional source of magnesium, dietary supplements are a viable second option. Magnesium supplements come in a number of different forms, and some are more easily absorbed by the body than others. Among the different magnesium supplements is magnesium oxide.
Magnesium oxide is comprised of magnesium and oxygen ions. It’s available in supplement form, typically as a tablet or capsule. You can purchase magnesium oxide without a prescription.
Magnesium oxide doesn’t absorb into the bloodstream as easily as other magnesium compounds, and may cause, “gastrointestinal upset in some individuals,” according to Dr. Pearlman. This means that while magnesium oxide contains high traces of elemental magnesium (the actual amount of magnesium present), this form may have limited effectiveness in boosting the body’s magnesium levels, making it not the best option for those who are deficient—however, it may offer other health benefits.
“Magnesium oxide dosages can range from 100 milligrams to 400 milligrams, depending on the individual’s needs,” says Anya Rosen, a New York-based registered dietitian. The right dosage for you will depend on your purpose for use, whether that’s to relieve constipation or heartburn. You should always consult with a doctor for a personalized recommendation.
Although magnesium oxide has a low absorption rate, it still has its share of potential health benefits. “Magnesium oxide is a popular form of magnesium because of its low cost and widespread availability,” says Dr. Pearlman. The fact that magnesium oxide is such a strong laxative makes it an ideal supplement or over-the-counter solution for people facing digestive issues.
The supplement is often used to support the treatment of the following symptoms, either as a laxative or antacid:
“Magnesium oxide is considered an osmotic laxative in that it draws water into the intestines,” says Dr. Pearlman. “This increased volume also stimulates the intestinal wall and propulsive motor activity to help relieve constipation in both children and adults.”
Magnesium oxide is relatively safe when taken in the recommended doses. However, it can cause the following mild side effects:
Its intense laxative effects can loosen bowels to the point of diarrhea, according to Rosen. Because of this, she advises that, “magnesium oxide should only be used under [the] supervision of a licensed health practitioner and as a short-term remedy for constipation.”
In more severe cases, users may experience the serious side effects listed below. You should call a doctor if you encounter any of these side effects following intake of magnesium oxide:
You should limit use of magnesium oxide as a laxative for no more than one week, according to the National Library of Medicine. If you’re using it as an antacid to relieve heartburn or acid indigestion, limit use to two weeks.
Experts also recommend that if a person has a magnesium deficiency, after supplementation, it’s important to increase organic vegetable intake of foods high in magnesium.
Moon Juice's Magnesi-Om contains 3 bioavailable forms of Magnesium plus L-Theanine to help restore cellular balance for relaxation, sleep, brain health, and regularity.
Before adding a magnesium oxide supplement to your dietary routine, you should chat with a doctor to ensure you’re using the right dosage for your personal health history. Your provider can help you, “find out the best magnesium formulation for your particular condition or symptom to optimize results and limit potential side effects,” says Dr. Pearlman. They can also help monitor your magnesium levels to help prevent hypermagnesemia.
It’s also very important to, “consult a doctor if you are pregnant [or chest-feeding], on medications or have any disease or illness that interferes with mineral status,” adds Rosen. Medications like aspirin, anticoagulants (blood thinners), diuretics (water pills) and other laxatives or antacids are of primary concern, as they may not interact well with magnesium oxide supplements.
If you have kidney, heart, liver or intestinal disease or high blood pressure and you’d like to take magnesium oxide, you should first seek approval from a doctor. The same goes for those on a restrictive diet (i.e., low-salt or low-sugar) and with special nutritional needs.
Information provided on Forbes Health is for educational purposes only. Your health and wellness is unique to you, and the products and services we review may not be right for your circumstances. We do not offer individual medical advice, diagnosis or treatment plans. For personal advice, please consult with a medical professional.
Forbes Health adheres to strict editorial integrity standards. To the best of our knowledge, all content is accurate as of the date posted, though offers contained herein may no longer be available. The opinions expressed are the author’s alone and have not been provided, approved or otherwise endorsed by our advertisers.
Johnaé De Felicis is a health writer and passionate wellpreneur. Her mission in life is to inspire others to lead happy, healthy and wholesome lives, and she covers a variety of topics that are centered around this goal. Johnaé's work also appears in Healthline, Well+Good and Blue Zones.
Magnesium Oxide For Glasses Dr. Elliot Dinetz is double board certified in Family Medicine and Functional Medicine where he understood early on that this is the true path for optimal health and longevity. After completing his fellowship, his practice focuses on targeting root cause health issues and customizing health plans based on decoding genetic risks and health strengths for each person. This has helped him deliver unprecedented care, proving to be the next step of evolution in our healthcare system. Dr. Dinetz now lives and practices in Miami, Florida where he started his practice, Timeless Health. He dedicates time outside of practice lecturing to other integrative physicians on leading edge clinical genomics and research, as well as community education on wellness, nutrition and lifestyle. Dr. Dinetz is a member of the Institute of Functional Medicine (IFM), The Florida Medical Association (FMA) while holding medical licensure in the states of Georgia, Florida and California.