Magnesium plays a role in more than 300 of the body’s enzyme reactions. It contributes significantly to the:

  • health of muscles and nerves
  • regulation of blood pressure
  • production of energy in the body’s cells
  • synthesis of DNA and RNA

So, it’s pretty important to make sure that you are getting enough.


Lethargy, drowsiness, hypotension, nausea, vomiting, facial flushing, urinary retention, and ileus may be the initial symptoms observed when magnesium blood level exceeds 4–6 mg/dl. If untreated, this condition may progress to flaccid skeletal muscular paralysis and hyporeflexia, bradycardia and bradyarrhythmia, complete heart block, and respiratory depression. However, hypermagnesemia is an uncommon laboratory finding and symptomatic hypermagnesemia is even less common. This disorder has a low incidence of occurrence, because the kidney is able to eliminate excess magnesium by rapidly reducing its tubular reabsorption to almost negligible amounts. Most cases of hypermagnesemia occur in people who have kidney failure. Hypermagnesemia occurs because the process that keeps the levels of magnesium in the body at normal levels does not work properly in people with kidney dysfunction and end-stage liver disease.


A doctor will usually consider a diagnosis of hypomagnesemia where there are fewer than 1.8 milligrams of magnesium per deciliter of blood. Deficiencies do not always cause problems, but some early symptoms include muscle twitching, numbness, and tingling. If left untreated, hypomagnesemia can cause chronic health problems and decrease the body’s levels of calcium and potassium.

People with mild hypomagnesemia may have no symptoms, but these can include:

  • twitches, particularly in the facial muscles
  • weakness and exhaustion
  • nausea and vomiting
  • personality changes
  • tremors
  • very pronounced reflexes
  • constipation

More severe magnesium deficiency can cause:

  • muscle contractions
  • seizures
  • changes in the heart’s rhythm

Magnesium Supplements

Sometimes, magnesium supplements are prescribed for reasons other than having a low magnesium level. Common uses of magnesium include pain management (bone pain, muscle pain, menstrual pain, migraines and muscle spasms), constipation, depression, and for high blood pressure. When you’re taking a magnesium supplement, it is important to know what you are taking the supplement for as that can effect the way that you want to take it.

Not all types of magnesium supplements are absorbed by the body equally and this changes what they are most helpful for. The types of magnesium that have the highest bioavailability are the easiest to absorb and are the best choices for pain management and to increase low magnesium levels. The types of magnesium with low bioavailability are difficult for the body to absorb and are more suited for the purpose of laxatives.

Magnesium citrate — Magnesium citrate is the most popular magnesium supplement, probably because
it is inexpensive and easily absorbed. Since citric acid is a mild laxative, magnesium citrate functions as a
constipation aid as well as a magnesium source. It is a great choice for individuals with rectal or colon
problems but is unsuitable for those with loose bowel movements.

Magnesium taurate — Magnesium taurate is the best choice of magnesium supplement for people with
cardiovascular issues, since it is known to prevent arrhythmias and guard the heart from damage caused
by heart attacks. Magnesium taurate is easily absorbed (magnesium and taurine stabilize cell
membranes together), and it contains no laxative properties.

Magnesium malate — Magnesium malate is a fantastic choice for people suffering from fatigue, since
malic acid — a natural fruit acid present in most cells in the body — is a vital component of enzymes that
play a key role in ATP synthesis and energy production. Since the ionic bonds of magnesium and malic
acid are easily broken, magnesium malate is also highly soluble.

Magnesium glycinate — Magnesium glycinate (magnesium bound with glycine, a non-essential amino
acid) is one of the most bioavailable and absorbable forms of magnesium, and also the least likely to
induce diarrhea. It is the safest option for correcting a long-term deficiency.

Magnesium chloride — Though magnesium chloride only contains around 12 percent elemental
magnesium, it has an impressive absorption rate and is the best form of magnesium to take for detoxing
the cells and tissues. Moreover, chloride (not to be confused with chlorine, the toxic gas) aids kidney
function and can boost a sluggish metabolism.

Magnesium carbonate — Magnesium carbonate is another popular, bioavailable form of magnesium
that actually turns into magnesium chloride when it mixes with the hydrochloric acid in our stomachs. It
is a good choice for people suffering from indigestion and acid reflux, since it contains antacid

Magnesium oxide — Magnesium oxide is the most common form of magnesium sold in pharmacies, but
it is non-chelated and possesses a poor absorption rate compared to those listed above.

Magnesium sulfate — Magnesium sulfate, also called Epsom salt, is a fantastic constipation aid but an
unsafe source of dietary magnesium, since overdosing on it is easy.

Assuming that you are not using the magnesium for constipation, you should not have loose stools when taking a magnesium supplement. If this occurs, consider trying a different kind of magnesium supplement. Keep in mind that everyone’s body is different and having loose stools with magnesium is indicative that your body is not absorbing the kind of magnesium that you are taking. When we fail to absorb magnesium from our gut it acts as a laxative because it draws water into the bowel. This is why magnesium citrate and milk of magnesia are such common constipation medications. So, you may want to do some trials of different kinds of magnesium to see which is best absorbed by your gut.

Taking small doses several times a day rather then a single large dose can reduce the laxative effect of taking any type of magnesium. It can be helpful to either cut your tablets or even get pediatric tablets so that you can really reduce the dose down. You can also get a powder form supplement that will give you immense dosing control. The powder can be taken by mixing it into food or fluid.

Taking a fiber tablet or powder at the same time that you take the magnesium can help reduce the laxative effective as the fiber will absorb the water. However, there are limits to what fiber can do to help with this problem and is more helpful if you are adding it in with other strategies rather then using it alone. Additionally, using fiber does not help your body absorb the magnesium. All the fiber will do is absorb the water that the magnesium is drawing into your gut. This is a great bulking strategy if you are using magnesium as a laxative. Otherwise, fiber isn’t very helpful since you will still be loosing the magnesium through your bowel.

Reducing your consumption of sugar, salt, alcohol, coffee and tea can be helpful; especially within a few hours of taking the magnesium. These substances reduce our ability to absorb magnesium. Review the side effects of your other medications as there might be some that also cause loose stools that you should avoid taking with the magnesium dosing time. Most people only tolerate taking one kind of magnesium at a time. Additionally, by taking more then one type at a time, if you are having loose stools, it becomes impossible to tell which is not being absorbed properly. It could be both or just one of them that is causing the problem. It may be just that it’s too much to be taking them together.

It is helpful to titrate up your magnesium dose by starting with a quarter of the dose or smaller and increasing every 2 or 3 weeks until reaching the goal dose. Some of the loose stool side effect will abate as your gut becomes accustomed to the magnesium, but it is not likely that this alone will fully resolve the problem.

Magnesium and Diet

  • Men: 400–420 mg
  • Women: 310–320 mg

How much magnesium is in your food?

  • Pumpkin seed – kernels: Serving Size 1 oz, 168 mg
  • Almonds, dry roasted: Serving Size 1 oz, 80 mg
  • Spinach, boiled: Serving Size ½ cup, 78 mg
  • Cashews, dry roasted: Serving Size 1 oz, 74 mg
  • Pumpkin seeds in shell: Serving Size 1 oz, 74 mg
  • Peanuts, oil roasted: Serving Size ¼ cup, 63 mg
  • Cereal, shredded wheat: Serving Size 2 large biscuits, 61 mg
  • Soymilk, plain or vanilla: Serving Size 1 cup, 61 mg
  • Black beans, cooked: Serving Size ½ cup, 60 mg
  • Edamame, shelled, cooked: Serving Size ½ cup, 50 mg
  • Dark chocolate -60-69% cacoa: Serving Size 1 oz, 50 mg

Your PCP

Your Primary Care Provider (PCP) really will be your best ally when managing a supplement. They will be the person that will be ordering your monitoring lab work to make sure that your supplementation is meeting your goals. They will also be the ones that will help you make sure that you are taking the right amount of the supplement. Not to mention it is most likely going to be your PCP who is helping you manage those underlying conditions that is causing you to have to take a supplement in the first place. It is also possible that your supplements could interact with medications that you are taking. Your PCP and your pharmacist are your best allies for monitoring for these possible interactions. So it is super important to keep your doctor in the loop whenever you are adding in supplements.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.