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What Happens to Your Body When You Take Magnesium

Experts explain everything to know about magnesium.
FACT CHECKED BY Emilia Paluszek

According to the Mayo Clinic, many Americans don't get enough magnesium, which is an essential nutrient for energy levels, helps maintain muscle and nerve function, keeps blood pressure normal, heart rhythm steady and bones strong. While you should be able to get the recommended daily intake of magnesium, which is 400-420 mg daily for adult men and 310-320 mg for women, according to Harvard Health, from your diet, there are supplements as well. But before you start popping vitamins, speak to your doctor and read the tips below experts told Eat This, Not That! Health about magnesium. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


What is Magnesium and Why Is It Important?


Dr. David Culpepper, MD and Clinical DIrector of LifeMD says, "Magnesium is an essential nutrient that has a number of important functions within the body. It helps regulate the nervous system as well as muscle function, helps to maintain blood sugar levels and blood pressure, and is an essential building block when the body makes new bone, protein, and even DNA. Magnesium also lowers the likelihood of high blood pressure and Type 2 diabetes. Over the long term, a deficiency in magnesium can lead to symptoms such as weakness, nausea or loss of appetite, fatigue or weakness, or vomiting. A severe deficiency can lead to symptoms like muscle cramps, tingling or numbness, or even arrhythmia or seizures." 


What Happens When You Lack Magnesium and How to Avoid a Magnesium Deficiency?

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Dr. Sunjya Schweig, MD, founder of California Center for Functional Medicine explains, "Lacking magnesium can be predisposed by chronic stress, autoimmune conditions, chronic inflammation, poor gut health, high carb and sugar diet, and hormonal imbalances. Some of the neuromuscular signs include tremors or muscle twitches and cramps, seizures, tetany and delirium. Cardiovascular manifestations include atrial fibrillation, arrhythmias and cardiac ischemia. Other signs include osteoporosis, fatigue, sleep issues, low immunity, anxiety and mood disorders, high blood pressure and poor recovery from exercise." 

Kristian Morey, RD, LDN, is a Clinical Dietitian with the Nutrition and Diabetes Education program at Mercy Medical Center in Baltimore says, "Early signs of magnesium deficiency can be loss of appetite, nausea, vomiting, fatigue, and weakness. Worsening deficiency is characterized by signs like numbness, tingling, muscle cramps, seizures, and abnormal heart rhythm. You can reduce your risk for a deficiency by having a varied diet that includes green leafy vegetables, legumes, nuts, seeds, and whole grains."

Khara' Jefferson, DNP, APRN, FNP-Cwner, KAJ Wellness adds, "Magnesium deficiency is quite common, especially in African American and the elderly. Chronically low levels can lead to osteoporosis, and increase risk of diabetes, hypertension, and heart disease. Unfortunately, hypomagnesemia typically has no symptoms. Stress increases magnesium loss, which in turn increases stress on the body. If you are deficient in magnesium, you are more likely to have higher inflammatory markers. High intake of Vitamin D can deplete magnesium, so you should ensure you have sufficient magnesium levels (RBC Magnesium lab test) before beginning supplementation. (Serum magnesium levels typically do not correlate with body magnesium levels). Also, magnesium uptake is impaired when using proton-pump inhibitor (PPI) and histamine receptor blocker medications and insulin resistance. More magnesium is excreted with diuretics, diarrhea, and drugs that increase urination. High doses of calcium and zinc can also decrease the dietary absorption of magnesium. Chronic alcohol use increases the risk for magnesium deficiency, so use alcohol sparingly. Poorly controlled diabetes can also increase the risk for deficiency since renal reabsorption is typically impaired. Gastric bypass surgery also impairs magnesium absorption."


What to Know Before Taking Magnesium Supplements

magnesium pills

Morey explains, "It's always best to discuss taking a supplement with your healthcare provider first. For example, if you take a laxative already, it may have magnesium as a main ingredient and you could be taking too much and giving yourself GI woes in the form of diarrhea, nausea, or abdominal cramping. You may also take a medication that interacts with magnesium supplements. Finally, it is helpful to  note that supplements that dissolve in water are better absorbed than less soluble forms. All of these factors may go into your provider's assessment as to whether supplementation is advisable for you."

Jefferson says, "There are multiple forms of magnesium salts, and each form has a different use. It's also important to note that not all forms are easily absorbed by the body, so it is important to contact your provider before using it. Additionally, magnesium can interfere with some medications so should be used cautiously to prevent adverse effects. It is also a cofactor for many processes. When taking magnesium supplements, these should be started slowly. They are typically taken in divided doses to minimize the impact on the gut as a bolus and to optimize its absorption. If someone has kidney concerns or disease, they should use magnesium with caution, as it reduces magnesium excretion and can lead to hypermagnesemia."

Gita Castallian, MPH Public Health Analyst with California Center for Functional Medicine says, "There are many different types of magnesium supplements. The choice of magnesium type depends on your particular needs such as anxiety, muscle health, sleep or energy. 

  • Magnesium glycinate is a great choice for sleep support and studies have shown it helps to promote relaxation. It is gentle on the stomach and is easily absorbed by the body. 
  • Magnesium citrate is another popular form of magnesium supplements and, like glycinate, it is easily absorbed by the body. It additionally helps to stimulate digestion and can help to relieve constipation. 
  • Magnesium oxide tends to have a lower absorption rate, but can still be effective if taken in higher amounts. It can help to reduce stomach acid. 
  • Magnesium sulfate, also known as epsom salts, can be put in a bath to help deal with sore muscles. In supplement form, it can encourage bowel movements" 


Pros of Taking Magnesium Supplements


Morey says the following are benefits to taking magnesium supplements.

Jefferson shares, "It can help with sleep, brain fog, muscle soreness, acid reflux, constipation, and so many other conditions. It is generally regarded as safe if people are under the care of an experienced professional. Many of the forms can support someone's unique needs. For example, taking magnesium citrate for constipation is common. It is found OTC, as is Epsom salt, commonly used to help with tight muscles. It is beneficial for those who take medications that deplete magnesium and it can help with stress!"


Cons of Taking Magnesium Supplements

stomach pain

Morey says to consider the following before taking magnesium supplements.

  • "It may make your pill regimen more complex if you have to time it around other medications that can interact with them, such as certain antibiotics and bisphosphonates.
  • Taking too much can cause the problems described above."

Jefferson explains, "Too much magnesium can cause diarrhea and less commonly, abdominal cramping and nausea. Magnesium can interfere with certain medications and may already be found in other products you are routinely taking like laxatives, or antacids, so check with a doctor or pharmacist first."

Castallian adds, "Too much magnesium from food is not a typical concern, but with supplements, there is the possibility of having too much. High doses can cause side effects including nausea, stomach cramps and diarrhea. Additionally, magnesium can interact with some medications such as antibiotics." 


Best Ways to Get Magnesium

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Dr. Culpepper shares, "Fortunately, magnesium is found in many healthy foods such as leafy green vegetables, whole grains, beans, nuts, and seeds. It is also found in milk. It is also available in multivitamin supplements and on its own as a supplement. Most of the time, magnesium supplements can be taken without any issues. However, occasionally a surplus of magnesium can cause nausea or diarrhea. If you experience these symptoms, stop taking the supplements and consult with your physician."

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather